Abstract/Text
OBJECTIVE: The aim of the study was to examine the association of tested TSH with age, gender, and diabetes in a large population-based cohort without evidence of thyroid disease.
DESIGN: Record-linkage technology was used retrospectively to identify people without evidence of thyroid disease in the general population of Tayside, Scotland, from July 1, 2003, to December 31, 2009.
COHORT: All Tayside residents who had thyroid function tests performed were identified. Using a unique patient identifier, data linkage enabled a cohort without thyroid disease to be identified by excluding anyone with thyroid or antithyroid prescription, thyroid-related admission or surgery, treatment with radioactive iodine and/or positive thyroid antibodies. Cases below 18 years of age were also excluded.
OUTCOME MEASURES: We measured TSH distribution among different age groups and by gender.
RESULTS: We identified the latest TSH measurements in 153127 people from the reference population after applying the exclusion criteria. There was a significant increase in median TSH (1.58 mU/L at 31-40 y to 1.86 mU/L at >90 y; P < .001) and 97.5th centile TSH (3.98 to 5.94 mU/L, respectively) with increasing age. The 2.5th centile decreased with age (0.51 to 0.31 mU/L). Patients with diabetes had marginally higher TSH concentration (1.80 vs 1.70 mU/L; P < .001).
CONCLUSION: The use of these age-specific reference intervals for TSH, especially in those over 70 years old, would result in the reclassification of many TSH results from "abnormal" to "normal" (within the 95th centile reference interval) and avoid unnecessary treatment.
Sergio Valdés, Cristina Maldonado-Araque, Ana Lago-Sampedro, Juan Antonio Lillo-Muñoz, Eduardo Garcia-Fuentes, Vidal Perez-Valero, Carolina Gutiérrez-Repiso, Eva Garcia-Escobar, Albert Goday, Inés Urrutia, Laura Peláez, Alfonso Calle-Pascual, Elena Bordiú, Luis Castaño, Conxa Castell, Elias Delgado, Edelmiro Menéndez, Josep Franch-Nadal, Sonia Gaztambide, Joan Girbés, Emilio Ortega, Joan Vendrell, Matilde R Chacón, F Javier Chaves, Federico Soriguer, Gemma Rojo-Martínez
Reference values for TSH may be inadequate to define hypothyroidism in persons with morbid obesity: Di@bet.es study.
Obesity (Silver Spring). 2017 Apr;25(4):788-793. doi: 10.1002/oby.21796. Epub 2017 Mar 9.
Abstract/Text
OBJECTIVE: To analyze the reference range of thyroid-stimulating hormone (TSH) in different BMI categories and its impact on the classification of hypothyroidism.
METHODS: The study included 3,928 individuals free of thyroid disease (without previous thyroid disease, no interfering medications, TSH <10 µUI/mL and thyroid peroxidase antibodies [TPO Abs] <50 IU/mL) who participated in a national, cross-sectional, population-based study and were representative of the adult population of Spain. Data gathered included clinical and demographic characteristics, physical examination, and blood and urine sampling. TSH, free thyroxine, free triiodothyronine, and TPO Ab were analyzed by electrochemiluminescence (E170, Roche Diagnostics, Basel, Switzerland).
RESULTS: The reference range (p2.5-97.5) for TSH was estimated as 0.6 to 4.8 µUI/mL in the underweight category (BMI<20 kg/m2 ), 0.6 to 5.5 µUI/mL in the normal-weight category (BMI 20-24.9 kg/m2 ), 0.6 to 5.5 µUI/mL in the overweight category (BMI 25-29.9 kg/m2 ), 0.5 to 5.9 µUI/mL in the obesity category (BMI 30-39.9 kg/m2 ), and 0.7 to 7.5 µUI/mL in the morbid obesity category (BMI ≥40). By using the reference criteria for the normal-weight population, the prevalence of high TSH levels increased threefold in the morbid obesity category (P < 0.01).
CONCLUSIONS: Persons with morbid obesity might be inappropriately classified if the standard ranges of normality of TSH for the normal-weight population are applied to them.
© 2017 The Obesity Society.
Abstract/Text
BACKGROUND: The use of age- and ethnicity-specific thyrotropin (TSH) reference limits decreases misclassification of patients with thyroid dysfunction. Developing such limits requires TSH measurements in different subpopulations.
METHODS: We determined, in the National Health and Nutrition Examination Survey III, the TSH median, 2.5th and 97.5th centiles as a function of age, and anti-thyroid antibodies (ABs) in specific racial/ethnic groups (REGs) designated as non-Hispanic Whites, non-Hispanic Blacks, and Mexican Americans, as classified by the U.S. Office of Management and Budget (OMB) Directive 15. We compared TSH limits of a thyroid disease-free population (n = 15,277) to a reference population (n = 13,344) formed by exclusion of AB+ subjects and TSH >10 mIU/L or <0.1 mIU/L. With quantile regression, we examined the effect of age, REG, gender, body weight, and urinary iodine concentration on TSH reference limits in the AB- population.
RESULTS: AB status did not affect the 2.5th centile and median TSH in any REG or the 97.5th centile in Blacks. The average 97.5th centile of the disease-free Whites and Mexican Americans was 1.0 mIU/L higher than the reference population group. The TSH 2.5th, 50th, and 97.5th centiles increased with age and were lower in Blacks than in Whites or Mexican Americans. Women had lower 2.5th and 50th centiles than males. From these data, we developed equations to predict subpopulation-specific TSH reference limits.
CONCLUSIONS: Our study provides a method to determine TSH limits in individual patients of different ages, gender, and REG criteria whose AB status is uncertain and it will enable clinicians to better classify patients within their subpopulation-specific TSH reference range.
Abstract/Text
Debate and controversy currently surround the recommendations of a recent consensus conference that considered issues related to the management of early, mild, or so-called subclinical hypothyroidism and hyperthyroidism. Intimately related to the controversy is the definition of the normal reference range for TSH. It has become clear that previously accepted reference ranges are no longer valid as a result of both the development of more highly sensitive TSH assays and the appreciation that reference populations previously considered normal were contaminated with individuals with various degrees of thyroid dysfunction that served to increase mean TSH levels for the group. Recent laboratory guidelines from the National Academy of Clinical Biochemistry indicate that more than 95% of normal individuals have TSH levels below 2.5 mU/liter. The remainder with higher values are outliers, most of whom are likely to have underlying Hashimoto thyroiditis or other causes of elevated TSH. Importantly, data indicating that African-Americans with very low incidence of Hashimoto thyroiditis have a mean TSH level of 1.18 mU/liter strongly suggest that this value is the true normal mean for a normal population. Recognition and establishment of a more precise and true normal range for TSH have important implications for both screening and treatment of thyroid disease in general and subclinical thyroid disease in particular.
Linda M Thienpont, Katleen Van Uytfanghe, Linde A C De Grande, Dries Reynders, Barnali Das, James D Faix, Finlay MacKenzie, Brigitte Decallonne, Akira Hishinuma, Bruno Lapauw, Paul Taelman, Paul Van Crombrugge, Annick Van den Bruel, Brigitte Velkeniers, Paul Williams, IFCC Committee for Standardization of Thyroid Function Tests (C-STFT)
Harmonization of Serum Thyroid-Stimulating Hormone Measurements Paves the Way for the Adoption of a More Uniform Reference Interval.
Clin Chem. 2017 Jul;63(7):1248-1260. doi: 10.1373/clinchem.2016.269456. Epub 2017 May 18.
Abstract/Text
BACKGROUND: The IFCC Committee for Standardization of Thyroid Function Tests developed a global harmonization approach for thyroid-stimulating hormone measurements. It is based on a multiassay method comparison study with clinical serum samples and target setting with a robust factor analysis method. Here we describe the Phase IV method comparison and reference interval (RI) studies conducted with the objective to recalibrate the participating assays and demonstrate the proof-of-concept.
METHODS: Fourteen manufacturers measured the harmonization and RI panel; 4 of them quantified the harmonization and first follow-up panel in parallel. All recalibrated their assays to the statistically inferred targets. For validation, we used desirable specifications from the biological variation for the bias and total error (TE). The RI measurements were done with the assays' current calibrators, but data were also reported after transformation to the new calibration status. We estimated the pre- and postrecalibration RIs with a nonparametric bootstrap procedure.
RESULTS: After recalibration, 14 of 15 assays met the bias specification with 95% confidence; 8 assays complied with the TE specification. The CV of the assay means for the harmonization panel was reduced from 9.5% to 4.2%. The RI study showed improved uniformity after recalibration: the ranges (i.e., maximum differences) exhibited by the assay-specific 2.5th, 50th, and 97.5th percentile estimates were reduced from 0.27, 0.89, and 2.13 mIU/L to 0.12, 0.29, and 0.77 mIU/L.
CONCLUSIONS: We showed that harmonization increased the agreement of results from the participating immunoassays, and may allow them to adopt a more uniform RI in the future.
© 2017 American Association for Clinical Chemistry.
Abstract/Text
CONTEXT: Thyroid dysfunction has been associated with both increased all-cause and cardiovascular mortality, but limited data are available on mild thyroid dysfunction and cause-specific mortality.
OBJECTIVE: The objective of the study was to examine the risk of all-cause mortality, major adverse cardiovascular events (MACEs), and cause-specific events in subjects with overt and subclinical thyroid dysfunction.
DESIGN: This was a retrospective cohort study.
SETTING AND PARTICIPANTS: Participants in the study were subjects who underwent thyroid blood tests, without prior thyroid disease, consulting their general practitioner in 2000-2009 in Copenhagen, Denmark.
MAIN OUTCOME MEASURE: All-cause mortality, MACEs, and cause-specific events identified in nationwide registries were measured.
RESULTS: A total of 47 327 (8.4%) deaths occurred among 563 700 included subjects [mean age 48.6 (SD ± 18.2) y; 39% males]. All-cause mortality was increased in overt and subclinical hyperthyroidism [age adjusted incidence rates of 16 and 15 per 1000 person-years, respectively; incidence rate ratios (IRRs) 1.25 [95% confidence interval (CI) 1.15-1.36] and 1.23 (95% CI 1.16-1.30)] compared with euthyroid (incidence rate of 12 per 1000 person-years). Risk of MACEs was elevated in overt and subclinical hyperthyroidism [IRRs 1.16 (95% CI 1.05-1.27) and 1.09 (95% CI 1.02-1.16)] driven by heart failure [IRRs 1.14 (95% CI 0.99-1.32) and 1.20 (95% CI 1.10-1.31)]. A reduction of all-cause mortality was observed in subclinical hypothyroidism with TSH of 5-10 mIU/L [IRR 0.92 (95% CI 0.86-0.98)].
CONCLUSIONS: Heart failure is the leading cause of an increased cardiovascular mortality in both overt and subclinical hyperthyroidism. Subclinical hypothyroidism with TSH 5-10 mIU/L might be associated with a lower risk of all-cause mortality.
Abstract/Text
OBJECTIVE: The association between subclinical hypothyroidism and hyperthyroidism and mortality in the elderly is poorly defined. This study was designed to evaluate the association between subclinical hypothyroidism and subclinical hyperthyroidism and mortality in the elderly and to define the thyroid-stimulating hormone values associated with excess mortality in the elderly.
METHODS: We performed a retrospective cohort study with a review of a computerized database of a large health care organization. Patients aged more than 65 years evaluated in the years 2002 to 2012 with documented normal free T4 values were included in the analysis. All cases of known thyroid disease or cases in which thyroid medications were dispensed were excluded. Analysis was performed only on individuals who were not treated for hyperthyroidism or hypothyroidism during the follow-up period. Subjects were divided into 3 groups based on thyroid-stimulating hormone values: normal (normal thyroid-stimulating hormone), subclinical hypothyroidism (thyroid-stimulating hormone >4.2 mIU/L), and subclinical hyperthyroidism (thyroid-stimulating hormone <0.35 mIU/L). All-cause mortality hazard ratio (HR) was compared among the 3 groups, and a subanalysis according to thyroid-stimulating hormone values was performed in those with subclinical hypothyroidism and subclinical hyperthyroidism.
RESULTS: A final analysis was performed on 17,440 individuals with subclinical thyroid disease (538 with subclinical hyperthyroidism [3.1%], 1956 with subclinical hypothyroidism [11.2%], 14,946 normal cases [85.7%], average age of 83 years, 10,289 were women) who were followed up for 10 years. Both subclinical hypothyroidism (HR, 1.75; confidence interval [CI], 1.63-1.88) and subclinical hyperthyroidism (HR, 2.33; CI, 2.08-2.63) were associated with significantly increased mortality, and this association persisted on multivariate analysis (subclinical hypothyroidism HR, 1.68; CI, 1.56-1.8, subclinical hyperthyroidism HR, 1.93; CI, 1.7-2.17). Crude mortality was elevated at 1, 2, and 5 years, but this association seemed to decrease as time from initial analysis increased (most significant association at 1 year). Thyroid-stimulating hormone values greater than 6.38 mIU/L were associated with the highest mortality in those with subclinical hypothyroidism after multivariate adjustment (HR, 1.708; CI, 1.38-2.12), whereas in subclinical hyperthyroidism, no threshold for increased mortality was identified. Mortality was higher.
CONCLUSIONS: Both subclinical hypothyroidism and subclinical hyperthyroidism are associated with increased mortality in the elderly. A threshold thyroid-stimulating hormone value (>6.35 mIU/L) exists for increased mortality in subclinical hypothyroidism, but not in subclinical hyperthyroidism.
Copyright © 2016 Elsevier Inc. All rights reserved.
Tinh-Hai Collet, Douglas C Bauer, Anne R Cappola, Bjørn O Asvold, Stefan Weiler, Eric Vittinghoff, Jacobijn Gussekloo, Alexandra Bremner, Wendy P J den Elzen, Rui M B Maciel, Mark P J Vanderpump, Jacques Cornuz, Marcus Dörr, Henri Wallaschofski, Anne B Newman, José A Sgarbi, Salman Razvi, Henry Völzke, John P Walsh, Drahomir Aujesky, Nicolas Rodondi, Thyroid Studies Collaboration
Thyroid antibody status, subclinical hypothyroidism, and the risk of coronary heart disease: an individual participant data analysis.
J Clin Endocrinol Metab. 2014 Sep;99(9):3353-62. doi: 10.1210/jc.2014-1250. Epub 2014 Jun 10.
Abstract/Text
CONTEXT: Subclinical hypothyroidism has been associated with increased risk of coronary heart disease (CHD), particularly with thyrotropin levels of 10.0 mIU/L or greater. The measurement of thyroid antibodies helps predict the progression to overt hypothyroidism, but it is unclear whether thyroid autoimmunity independently affects CHD risk.
OBJECTIVE: The objective of the study was to compare the CHD risk of subclinical hypothyroidism with and without thyroid peroxidase antibodies (TPOAbs).
DATA SOURCES AND STUDY SELECTION: A MEDLINE and EMBASE search from 1950 to 2011 was conducted for prospective cohorts, reporting baseline thyroid function, antibodies, and CHD outcomes.
DATA EXTRACTION: Individual data of 38 274 participants from six cohorts for CHD mortality followed up for 460 333 person-years and 33 394 participants from four cohorts for CHD events.
DATA SYNTHESIS: Among 38 274 adults (median age 55 y, 63% women), 1691 (4.4%) had subclinical hypothyroidism, of whom 775 (45.8%) had positive TPOAbs. During follow-up, 1436 participants died of CHD and 3285 had CHD events. Compared with euthyroid individuals, age- and gender-adjusted risks of CHD mortality in subclinical hypothyroidism were similar among individuals with and without TPOAbs [hazard ratio (HR) 1.15, 95% confidence interval (CI) 0.87-1.53 vs HR 1.26, CI 1.01-1.58, P for interaction = .62], as were risks of CHD events (HR 1.16, CI 0.87-1.56 vs HR 1.26, CI 1.02-1.56, P for interaction = .65). Risks of CHD mortality and events increased with higher thyrotropin, but within each stratum, risks did not differ by TPOAb status.
CONCLUSIONS: CHD risk associated with subclinical hypothyroidism did not differ by TPOAb status, suggesting that biomarkers of thyroid autoimmunity do not add independent prognostic information for CHD outcomes.
Abstract/Text
Subclinical thyroid dysfunction has been associated with coronary heart disease, but the risk of stroke is unclear. Our aim is to combine the evidence on the association between subclinical thyroid dysfunction and the risk of stroke in prospective cohort studies. We searched Medline (OvidSP), Embase, Web-of-Science, Pubmed Publisher, Cochrane and Google Scholar from inception to November 2013 using a cohort filter, but without language restriction or other limitations. Reference lists of articles were searched. Two independent reviewers screened articles according to pre-specified criteria and selected prospective cohort studies with baseline thyroid function measurements and assessment of stroke outcomes. Data were derived using a standardized data extraction form. Quality was assessed according to previously defined quality indicators by two independent reviewers. We pooled the outcomes using a random-effects model. Of 2,274 articles screened, six cohort studies, including 11,309 participants with 665 stroke events, met the criteria. Four of six studies provided information on subclinical hyperthyroidism including a total of 6,029 participants and five on subclinical hypothyroidism (n = 10,118). The pooled hazard ratio (HR) was 1.08 (95 % CI 0.87-1.34) for subclinical hypothyroidism (I (2) of 0 %) and 1.17 (95 % CI 0.54-2.56) for subclinical hyperthyroidism (I (2) of 67 %) compared to euthyroidism. Subgroup analyses yielded similar results. Our systematic review provides no evidence supporting an increased risk for stroke associated with subclinical thyroid dysfunction. However, the available literature is insufficient and larger datasets are needed to perform extended analyses. Also, there were insufficient events to exclude clinically significant risk from subclinical hyperthyroidism, and more data are required for subgroup analyses.
Layal Chaker, Christine Baumgartner, Wendy P J den Elzen, M Arfan Ikram, Manuel R Blum, Tinh-Hai Collet, Stephan J L Bakker, Abbas Dehghan, Christiane Drechsler, Robert N Luben, Albert Hofman, Marileen L P Portegies, Marco Medici, Giorgio Iervasi, David J Stott, Ian Ford, Alexandra Bremner, Christoph Wanner, Luigi Ferrucci, Anne B Newman, Robin P Dullaart, José A Sgarbi, Graziano Ceresini, Rui M B Maciel, Rudi G Westendorp, J Wouter Jukema, Misa Imaizumi, Jayne A Franklyn, Douglas C Bauer, John P Walsh, Salman Razvi, Kay-Tee Khaw, Anne R Cappola, Henry Völzke, Oscar H Franco, Jacobijn Gussekloo, Nicolas Rodondi, Robin P Peeters, Thyroid Studies Collaboration
Subclinical Hypothyroidism and the Risk of Stroke Events and Fatal Stroke: An Individual Participant Data Analysis.
J Clin Endocrinol Metab. 2015 Jun;100(6):2181-91. doi: 10.1210/jc.2015-1438. Epub 2015 Apr 9.
Abstract/Text
OBJECTIVE: The objective was to determine the risk of stroke associated with subclinical hypothyroidism.
DATA SOURCES AND STUDY SELECTION: Published prospective cohort studies were identified through a systematic search through November 2013 without restrictions in several databases. Unpublished studies were identified through the Thyroid Studies Collaboration. We collected individual participant data on thyroid function and stroke outcome. Euthyroidism was defined as TSH levels of 0.45-4.49 mIU/L, and subclinical hypothyroidism was defined as TSH levels of 4.5-19.9 mIU/L with normal T4 levels.
DATA EXTRACTION AND SYNTHESIS: We collected individual participant data on 47 573 adults (3451 subclinical hypothyroidism) from 17 cohorts and followed up from 1972-2014 (489 192 person-years). Age- and sex-adjusted pooled hazard ratios (HRs) for participants with subclinical hypothyroidism compared to euthyroidism were 1.05 (95% confidence interval [CI], 0.91-1.21) for stroke events (combined fatal and nonfatal stroke) and 1.07 (95% CI, 0.80-1.42) for fatal stroke. Stratified by age, the HR for stroke events was 3.32 (95% CI, 1.25-8.80) for individuals aged 18-49 years. There was an increased risk of fatal stroke in the age groups 18-49 and 50-64 years, with a HR of 4.22 (95% CI, 1.08-16.55) and 2.86 (95% CI, 1.31-6.26), respectively (p trend 0.04). We found no increased risk for those 65-79 years old (HR, 1.00; 95% CI, 0.86-1.18) or ≥ 80 years old (HR, 1.31; 95% CI, 0.79-2.18). There was a pattern of increased risk of fatal stroke with higher TSH concentrations.
CONCLUSIONS: Although no overall effect of subclinical hypothyroidism on stroke could be demonstrated, an increased risk in subjects younger than 65 years and those with higher TSH concentrations was observed.
Abstract/Text
Subclinical hypothyroidism (SCH), defined as elevated thyroid stimulating hormone (TSH) and normal thyroid hormone levels, and cognitive impairment are both common in older people. While the relation between overt hypothyroidism and cognitive impairment is well established, data on the association between SCH and cognitive impairment are conflicting. This systematic review and meta-analysis was performed to assess available evidence on the association of SCH with cognition in community dwelling, relatively healthy older adults. PubMed, EMBASE, Web of Science, COCHRANE, CINAHL, PsycINFO, and Academic Search Premier (January 1966 to April 1, 2015) were searched without language restrictions, as were references of key articles, for studies on the association between SCH and cognition in older adults (>60 years). These studies were reviewed by two independent reviewers according to predefined criteria for eligibility and methodological quality, and data were extracted using standardized forms. Of the 844 reports initially identified, 270 remained after exclusion of duplicates. Of the 270, 15 studies comprising 19,944 subjects, of whom 1,199 had subclinical hypothyroidism were included. Data from the 15 studies was pooled, and meta-analyzed cross-sectionally for global cognition [assessed by Mini-Mental State Examination (MMSE)], executive function, and memory, using random effects models. Pooled effect size (ES) for MMSE was -0.01 (95% CI -0.09, 0.08), with heterogeneity (I (2)) of 55.1%. Pooled ES was < 0.001 (95% CI -0.10, 0.09) for executive function (I (2) = 13.5%), and 0.01 (95% CI -0.12, 0.14) for memory (I (2) = 46.9%). In addition, prospective analysis including four studies showed pooled ES of 0.033 (95% CI -0.001 - 0.067) for MMSE (I (2) < 0.001%), indicating that subclinical hypothyroidism was not significantly associated with accelerated cognitive decline. This systematic review and meta-analysis provides no evidence that supports an association between SCH and cognitive impairment in relatively healthy older adults.
Nicolien A van Vliet, Diana van Heemst, Osvaldo P Almeida, Bjørn O Åsvold, Carole E Aubert, Jong Bin Bae, Linda E Barnes, Douglas C Bauer, Gerard J Blauw, Carol Brayne, Anne R Cappola, Graziano Ceresini, Hannie C Comijs, Jean-Francois Dartigues, Jean-Marie Degryse, Robin P F Dullaart, Marlise E A van Eersel, Wendy P J den Elzen, Luigi Ferrucci, Howard A Fink, Leon Flicker, Hans J Grabe, Ji Won Han, Catherine Helmer, Martijn Huisman, M Arfan Ikram, Misa Imaizumi, Renate T de Jongh, J Wouter Jukema, Ki Woong Kim, Lewis H Kuller, Oscar L Lopez, Simon P Mooijaart, Jae Hoon Moon, Elisavet Moutzouri, Matthias Nauck, Jim Parle, Robin P Peeters, Mary H Samuels, Carsten O Schmidt, Ulf Schminke, P Eline Slagboom, Eystein Stordal, Bert Vaes, Henry Völzke, Rudi G J Westendorp, Michiko Yamada, Bu B Yeap, Nicolas Rodondi, Jacobijn Gussekloo, Stella Trompet, Thyroid Studies Collaboration
Association of Thyroid Dysfunction With Cognitive Function: An Individual Participant Data Analysis.
JAMA Intern Med. 2021 Nov 1;181(11):1440-1450. doi: 10.1001/jamainternmed.2021.5078.
Abstract/Text
Importance: In clinical guidelines, overt and subclinical thyroid dysfunction are mentioned as causal and treatable factors for cognitive decline. However, the scientific literature on these associations shows inconsistent findings.
Objective: To assess cross-sectional and longitudinal associations of baseline thyroid dysfunction with cognitive function and dementia.
Design, Setting, and Participants: This multicohort individual participant data analysis assessed 114 267 person-years (median, 1.7-11.3 years) of follow-up for cognitive function and 525 222 person-years (median, 3.8-15.3 years) for dementia between 1989 and 2017. Analyses on cognitive function included 21 cohorts comprising 38 144 participants. Analyses on dementia included eight cohorts with a total of 2033 cases with dementia and 44 573 controls. Data analysis was performed from December 2016 to January 2021.
Exposures: Thyroid function was classified as overt hyperthyroidism, subclinical hyperthyroidism, euthyroidism, subclinical hypothyroidism, and overt hypothyroidism based on uniform thyrotropin cutoff values and study-specific free thyroxine values.
Main Outcomes and Measures: The primary outcome was global cognitive function, mostly measured using the Mini-Mental State Examination. Executive function, memory, and dementia were secondary outcomes. Analyses were first performed at study level using multivariable linear regression and multivariable Cox regression, respectively. The studies were combined with restricted maximum likelihood meta-analysis. To overcome the use of different scales, results were transformed to standardized mean differences. For incident dementia, hazard ratios were calculated.
Results: Among 74 565 total participants, 66 567 (89.3%) participants had normal thyroid function, 577 (0.8%) had overt hyperthyroidism, 2557 (3.4%) had subclinical hyperthyroidism, 4167 (5.6%) had subclinical hypothyroidism, and 697 (0.9%) had overt hypothyroidism. The study-specific median age at baseline varied from 57 to 93 years; 42 847 (57.5%) participants were women. Thyroid dysfunction was not associated with global cognitive function; the largest differences were observed between overt hypothyroidism and euthyroidism-cross-sectionally (-0.06 standardized mean difference in score; 95% CI, -0.20 to 0.08; P = .40) and longitudinally (0.11 standardized mean difference higher decline per year; 95% CI, -0.01 to 0.23; P = .09). No consistent associations were observed between thyroid dysfunction and executive function, memory, or risk of dementia.
Conclusions and Relevance: In this individual participant data analysis of more than 74 000 adults, subclinical hypothyroidism and hyperthyroidism were not associated with cognitive function, cognitive decline, or incident dementia. No rigorous conclusions can be drawn regarding the role of overt thyroid dysfunction in risk of dementia. These findings do not support the practice of screening for subclinical thyroid dysfunction in the context of cognitive decline in older adults as recommended in current guidelines.
Abstract/Text
In this study, we aimed to evaluate site-specific cancer risks associated with hyperthyroidism or hypothyroidism. We performed a systematic review of observational studies reporting associations between hyperthyroidism or hypothyroidism and subsequent site-specific cancer incidence, in MEDLINE and the COCHRANE library (inception-28/01/2019) (PROSPERO: CRD42019125094). We excluded studies with thyroid dysfunction evaluated as a cancer biomarker or after prior cancer diagnosis and those considering transient thyroid dysfunction during pregnancy or severe illnesses. Risk of bias was assessed using a modified Newcastle-Ottawa scale. Risk estimates were pooled using random-effects models when ≥5 studies reported data for a specific cancer site. Twenty studies were included, of which 15 contributed to the meta-analysis. Compared to euthyroidism, hyperthyroidism was associated with higher risks of thyroid (pooled risk ratio: 4.49, 95%CI: 2.84-7.12), breast (pooled risk ratio: 1.20, 95%CI: 1.04-1.38), and prostate (pooled risk ratio: 1.35, 95%CI: 1.05-1.74), but not respiratory tract (pooled risk ratio: 1.06, 95%CI: 0.80-1.42) cancers. Hypothyroidism was associated with a higher risk of thyroid cancer within the first 10 years of follow-up only (pooled risk ratio: 3.31, 95%CI: 1.20-9.13). There was no or limited evidence of thyroid dysfunction-related risks of other cancer sites. In conclusion, thyroid dysfunction was associated with increased risks of thyroid, breast, and prostate cancers. However, it remains unclear whether these findings represent causal relationships because information on treatments and potential confounders was frequently lacking.
Abstract/Text
BACKGROUND: Thyroid hormone has been shown to be involved in carcinogenesis via its effects on cell proliferation pathways. The objective of this study is to determine the association between subclinical hypothyroidism (SCH) and the risk of incident cancer and cancer mortality via systematic review.
METHODS: A systematic search was performed on Medline and Pubmed to identify relevant studies. Randomized controlled trials, and observational studies assessing SCH or its treatment and the risk of incident cancer or cancer mortality were identified.
RESULTS: A total of 7 cohort and 2 case-control studies met our inclusion criteria. In general, these studies were of medium to good quality. Overall, studies revealed no association between SCH and breast and prostate cancer. One study found that untreated SCH may be associated with an increased risk of colorectal cancer (adjusted odds ratio [OR]: 1.16; 95% confidence interval [CI]: 1.08-1.24). One study showed an increased risk in thyroid cancer incidence (adjusted OR: 3.38; 95% CI: 2.05-5.59) associated with elevation of a thyroid stimulating hormone (TSH) of > 1.64mIU/L. Two studies found an increase in cancer mortality among patients with SCH compared to euthyroid individuals; in contrast one study found no association between subclinical hypothyroidism and cancer mortality among aging men.
CONCLUSION: The number of studies examining thyroid dysfunction and cancer risk and mortality is limited. Future studies assessing the association between thyroid dysfunction and cancer risk and mortality are needed, which will further address the need to treat subclinical hypothyroidism.
Abstract/Text
Thyroid diseases are characterized by a wide range of physical and mental symptoms that can affect biological function, emotional and social life of patients. However, their impact on work functioning is not yet fully understood. Therefore, this review aims to address the way in which thyroid diseases can affect occupational outcomes, i.e., the employment rate, sick leave, working capacity and work income of patients. A systematic review of Pubmed, Scopus and ISI Web of Knowledge databases has been performed. Although it is not possible to extrapolate precise data for benign pathologies, about a third of the survivors of thyroid cancer could be unemployed. Hyperthyroid and hypothyroid patients presented a greater risk of long-term sick leave than controls, depending on the severity of the disease. Hyperthyroidism impaired working ability in about a third of affected patients, particularly in cases complicated by orbitopathy with diplopia. A possible influence of thyroid diseases on various occupational outcomes emerged from our review, however further research seems necessary to understand the relationship between work problems, specific pathological characteristics over time and risk factors in the workplace. This may support a comprehensive, interdisciplinary management of thyroid disorders, with benefits for patients' personal, social and professional life.
Abstract/Text
BACKGROUND AND AIMS: The involvement of thyroid autoimmunity and dysfunction in patients with chronic hepatitis C virus (HCV) infection before interferon-α (IFN-α) therapy remains controversial. We performed this meta-analysis to evaluate the association of HCV infection with the presence of anti-thyroid antibodies and dysthyroidism.
METHODS: A literature search was carried out to collect articles dated up to August 2015 to identify observational studies which compared the prevalence of anti-thyroid antibodies and thyroid dysfunction in IFN-α naïve chronic HCV-infected subjects with non-HCV infected controls. Random-effect or fixed-effect meta-analyses were applied and results reported as odds ratios (ORs) with 95% confidence intervals (CIs).
RESULTS: Twelve studies were included, involving 1,735 HCV-infected and 1,868 non-HCV infected subjects. Pooled anti-thyroid antibody prevalence tended to be higher in HCV-infected subjects. The prevalence of anti-thyroglobulin antibody (TGAb), anti-thyroid peroxidase antibody (TPOAb), anti-thyroid microsomal antibody (ATMA) were 2.40-fold, 1.96-fold and 1.86-fold higher in HCV-infected subjects than in controls, respectively. The prevalence of hypothyroidism also differed by HCV infection status, with a pooled risk of 3.10 (95%CI: 2.19-4.40) in HCV-infected subjects. However, the results did not show a significant difference in the prevalence of hyperthyroidism between the two groups.
CONCLUSION: Chronic HCV infection may be an independent risk factor for thyroid disturbance. It is advisable for the clinicians to monitor both thyroid antibodies and function in the course of chronic HCV infection, independent of IFN-α treatment.
Abstract/Text
CONTEXT: Thyroid disease in pregnancy is increasing with rising average maternal ages in developed countries. The evidence for an association between preterm birth and thyroid disease has been confounded by small studies with varying outcomes and methodology.
OBJECTIVE: The aim of this meta-analysis is to review the literature regarding thyroid disease including subclinical and overt hypothyroidism, hyperthyroidism, and isolated hypothyroxinemia and the specific outcome of preterm birth.
DATA SOURCES: A search of PubMed and Embase databases was performed in May 2015. A fixed-effects model was used to calculate the overall combined odds ratio (OR) with its corresponding 95% confidence interval (95% CI) to evaluate the relationship between thyroid disease and preterm delivery.
STUDY SELECTION: Studies were considered eligible if they met the following criteria: prospective cohort study or a case control study; the exposure of interest was maternal thyroid disease, including subclinical hypothyroidism, overt hypothyroidism, hyperthyroidism, or isolated hypothyroxinemia; the outcome of interest was preterm delivery; and data regarding numbers of preterm births in each cohort were reported.
DATA EXTRACTION: Data were recorded in a database evidence table including any incidence data for maternal thyroid disease and preterm birth compared to a reference group.
DATA SYNTHESIS: Fourteen cohort studies and one case control study involving 2 532 704 participants were included. The combined OR of preterm delivery for pregnant women with overt hypothyroidism compared with the reference group was 1.19 (95% CI, 1.12-1.26; P < .00001). There was also a significant risk of preterm birth in women with hyperthyroidism (OR, 1.24 [95%, CI 1.17-1.31]; P < .00001). Subclinical hypothyroidism and isolated hypothyroxinemia showed no significant increase in OR. Sensitivity analysis made no change to these results.
CONCLUSION: Both overt hypothyroidism and hyperthyroidism are associated with a small but statistically significant increase in OR for preterm birth not seen in subclinical hypothyroidism or isolated hypothyroxinemia.
Abstract/Text
A prospective observational study was performed in pregnant women with known thyroid disease. We studied the effect of maternal thyroid function in the first half of pregnancy on the neurologic development of the infant in the first 2 y of life. Clinical and thyroid function data were collected from 20 pregnant women with known thyroid disease and their newborn children. Infants were divided into three groups according to their maternal thyroid function within the first half of pregnancy: Group A (n = 7): maternal subclinical hypothyroidism, Group B (n = 6): maternal euthyroidism, and Group C (n = 7): maternal hyperthyroidism or subclinical hyperthyroidism. Neurophysiologic, i.e. motor nerve conduction velocity and somatosensory evoked potentials and neurologic and developmental (Bayley scales) assessments were done. One infant, born to a mother with Graves' disease, developed transient hyperthyroidism. At the age of 6 and 12 mo, the mean mental developmental index (MDI) score was 16 points lower for infants in Group A than for those in Group B (p = 0.03 and 0.02, respectively). At the age of 24 mo, the mean MDI score was 6 points lower, which was not statistically significant. Neurophysiologic and neurologic assessments and the mean Psychomotor Developmental scores did not differ among the three groups. In conclusion, maternal subclinical hypothyroidism in the first half of pregnancy was associated with a lower mean MDI score in their infants during the first year of life.
Abstract/Text
CONTEXT: Thyroid diseases are inconsistently reported to increase risk for pregnancy complications.
OBJECTIVE: The objective of this study was to study pregnancy complications associated with common and uncommon thyroid diseases.
DESIGN, SETTING, AND PARTICIPANTS: We analyzed singleton pregnancies (N = 223 512) from a retrospective US cohort, the Consortium on Safe Labor (2002-2008). Thyroid diseases and outcomes were derived from electronic medical records. Multivariable logistic regression with generalized estimating equations estimated adjusted odds ratios (ORs) with 99% confidence intervals (99% CI).
MAIN OUTCOME MEASURES: Hypertensive diseases, diabetes, preterm birth, cesarean sections, inductions, and intensive care unit (ICU) admissions were analyzed.
RESULTS: Primary hypothyroidism was associated with increased odds of preeclampsia (OR = 1.47, 99% CI = 1.20-1.81), superimposed preeclampsia (OR = 2.25, 99% CI = 1.53-3.29), gestational diabetes (OR = 1.57, 99% CI = 1.33-1.86), preterm birth (OR = 1.34, 99% CI = 1.17-1.53), induction (OR = 1.15, 99% CI = 1.04-1.28), cesarean section (prelabor, OR = 1.31, 99% CI = 1.11-1.54; after spontaneous labor OR = 1.38, 99% CI = 1.14-1.66), and ICU admission (OR = 2.08, 99% CI = 1.04-4.15). Iatrogenic hypothyroidism was associated with increased odds of placental abruption (OR = 2.89, 99% CI = 1.14-7.36), breech presentation (OR = 2.09, 99% CI = 1.07-4.07), and cesarean section after spontaneous labor (OR = 2.05, 99% CI = 1.01-4.16). Hyperthyroidism was associated with increased odds of preeclampsia (OR = 1.78, 99% CI = 1.08-2.94), superimposed preeclampsia (OR = 3.64, 99% CI = 1.82-7.29), preterm birth (OR = 1.81, 99% CI = 1.32-2.49), induction (OR = 1.40, 99% CI = 1.06-1.86), and ICU admission (OR = 3.70, 99% CI = 1.16-11.80).
CONCLUSIONS: Thyroid diseases were associated with obstetrical, labor, and delivery complications. Although we lacked information on treatment during pregnancy, these nationwide data suggest either that there is a need for better thyroid disease management during pregnancy or that there may be an intrinsic aspect of thyroid disease that causes poor pregnancy outcomes.
Tim I M Korevaar, Sarah Schalekamp-Timmermans, Yolanda B de Rijke, W Edward Visser, Willy Visser, Sabine M P F de Muinck Keizer-Schrama, Albert Hofman, H Alec Ross, Herbert Hooijkaas, Henning Tiemeier, Jacoba J Bongers-Schokking, Vincent W V Jaddoe, Theo J Visser, Eric A P Steegers, Marco Medici, Robin P Peeters
Hypothyroxinemia and TPO-antibody positivity are risk factors for premature delivery: the generation R study.
J Clin Endocrinol Metab. 2013 Nov;98(11):4382-90. doi: 10.1210/jc.2013-2855. Epub 2013 Sep 13.
Abstract/Text
CONTEXT: Premature delivery is an important risk factor for child mortality and psychiatric, metabolic, and cardiovascular disease later in life. In the majority of cases, the cause of prematurity cannot be identified. Currently, it remains controversial whether abnormal maternal thyroid function during pregnancy increases the risk of premature delivery. Therefore, we investigated the relation between maternal serum thyroid parameters and the risk of premature delivery in a large prospective population-based study.
DESIGN: Serum TSH, free T4 (FT4), T4, and TPO antibodies (TPOAbs) were determined during early pregnancy in 5971 pregnant women from the Generation R study. Data were available on maternal age, parity, smoking, socioeconomic status, ethnicity, maternal anthropometrics, and urinary iodine levels.
RESULTS: Of all women, 5.0% had a premature delivery (<37 weeks), 4.4% had a spontaneous premature delivery, and 1.4% had a very premature delivery (<34 weeks). High TSH levels and subclinical hypothyroidism were associated with premature delivery but not with spontaneous premature delivery. Maternal hypothyroxinemia was associated with a 2.5-fold increased risk of premature delivery, a 3.4-fold increased risk of spontaneous premature delivery, and a 3.6-fold increased risk of very premature delivery (all P < .01). TPOAb positivity was associated with a 1.7-fold increased risk of premature delivery (P = .01), a 2.1-fold increased risk of spontaneous premature delivery (P = .02), and a 2.5-fold increased risk of very premature delivery (P = .04). These effects remained similar after correction for TSH and FT4 levels.
CONCLUSIONS: Hypothyroxinemia and TPOAb positivity are associated with an increased risk of premature delivery. The increased risk in TPOAb-positive women seems to be independent of thyroid function.
Haixia Liu, Zhongyan Shan, Chenyan Li, Jinyuan Mao, Xiaochen Xie, Weiwei Wang, Chenling Fan, Hong Wang, Hongmei Zhang, Cheng Han, Xinyi Wang, Xin Liu, Yuxin Fan, Suqing Bao, Weiping Teng
Maternal subclinical hypothyroidism, thyroid autoimmunity, and the risk of miscarriage: a prospective cohort study.
Thyroid. 2014 Nov;24(11):1642-9. doi: 10.1089/thy.2014.0029. Epub 2014 Sep 17.
Abstract/Text
BACKGROUND: Increasing data suggest that subclinical hypothyroidism (SCH) and thyroid autoimmunity (TAI) are associated with adverse pregnancy outcomes, but there are limited data on the association of these conditions in early pregnancy with subsequent miscarriage.
METHODS: In this prospective cohort study, we screened 3315 women at low risk for thyroid dysfunction at four to eight weeks' gestation from iodine-sufficient areas of China between January 2012 and September 2012. Thyrotropin (TSH), free thyroxine (fT4), and the autoantibodies thyroid-peroxidase antibody (TPOAb) and thyroglobulin antibody (TgAb) were measured. Based on these results, women were divided into four groups for comparison: euthyroidism (ET), isolated SCH, isolated TAI (positive TPOAb or/and TgAb), and SCH with TAI (SCH+TAI). The SCH group was stratified into two subgroups (SCH 1 and SCH 2) on the basis of the level of TSH (2.5 ≤ TSH < 5.22 or 5.22 ≤ TSH < 10 respectively). Accordingly, the SCH+TAI group was also stratified into two subgroups (SCH+TAI 1 and SCH+TAI 2). The outcome of interest was miscarriage, defined as spontaneous pregnancy loss prior to 20 weeks.
RESULTS: Compared to women with ET, the risk of miscarriage was significantly higher among women with SCH 2 (7.1% vs. 2.2%, aOR 3.40 [CI 1.62-7.15]; p = 0.002), isolated TAI (5.7% vs. 2.2%, aOR 2.71 [CI 1.43-5.12]; p = 0.003), SCH+TAI 1 (10.0% vs. 2.2%, aOR 4.96 [CI 2.76-8.90]; p = 0.000), and SCH+TAI 2 (15.2% vs. 2.2%, aOR 9.56 [CI 3.76-24.28]; p = 0.000). The gestational ages of 110 women at miscarriage were lower among women with subclinical thyroid abnormalities compared to ET (11.13 ± 3.21 weeks with subclinical thyroid abnormalities vs. 9.33 ± 1.71 weeks with ET; p = 0.024). In parallel with the higher TSH levels, there were earlier gestation ages at miscarriage between subgroups of SCH and SCH+TAI (SCH 1 vs. SCH 2: 10.79 ± 1.77 vs. 9.70 ± 1.47 weeks, p = 0.039; SCH+TAI 1 vs. SCH+TAI 2: 9.59 ± 1.97 vs. 8.88 ± 1.24 weeks, p = 0.031).
CONCLUSIONS: Women with SCH and TAI are at an increased risk of miscarriage between four and eight gestational weeks. Women with a combination of SCH and TAI were found to have the highest risk and earlier gestational ages of miscarriage.
Arash Derakhshan, Robin P Peeters, Peter N Taylor, Sofie Bliddal, David M Carty, Margreet Meems, Bijay Vaidya, Liangmiao Chen, Bridget A Knight, Farkhanda Ghafoor, Polina V Popova, Lorena Mosso, Emily Oken, Eila Suvanto, Aya Hisada, Jun Yoshinaga, Suzanne J Brown, Judit Bassols, Juha Auvinen, Wichor M Bramer, Abel López-Bermejo, Colin M Dayan, Robert French, Laura Boucai, Marina Vafeiadi, Elena N Grineva, Victor J M Pop, Tanja G Vrijkotte, Leda Chatzi, Jordi Sunyer, Ana Jiménez-Zabala, Isolina Riaño, Marisa Rebagliato, Xuemian Lu, Amna Pirzada, Tuija Männistö, Christian Delles, Ulla Feldt-Rasmussen, Erik K Alexander, Scott M Nelson, Layal Chaker, Elizabeth N Pearce, Mònica Guxens, Eric A P Steegers, John P Walsh, Tim I M Korevaar
Association of maternal thyroid function with birthweight: a systematic review and individual-participant data meta-analysis.
Lancet Diabetes Endocrinol. 2020 Jun;8(6):501-510. doi: 10.1016/S2213-8587(20)30061-9.
Abstract/Text
BACKGROUND: Adequate transplacental passage of maternal thyroid hormone is important for normal fetal growth and development. Maternal overt hypothyroidism and hyperthyroidism are associated with low birthweight, but important knowledge gaps remain regarding the effect of subclinical thyroid function test abnormalities on birthweight-both in general and during the late second and third trimester of pregnancy. The aim of this study was to examine associations of maternal thyroid function with birthweight.
METHODS: In this systematic review and individual-participant data meta-analysis, we searched MEDLINE (Ovid), Embase, Web of Science, the Cochrane Central Register of Controlled Trials, and Google Scholar from inception to Oct 15, 2019, for prospective cohort studies with data on maternal thyroid function during pregnancy and birthweight, and we issued open invitations to identify study authors to join the Consortium on Thyroid and Pregnancy. We excluded participants with multiple pregnancies, in-vitro fertilisation, pre-existing thyroid disease or thyroid medication usage, miscarriages, and stillbirths. The main outcomes assessed were small for gestational age (SGA) neonates, large for gestational age neonates, and newborn birthweight. We analysed individual-participant data using mixed-effects regression models adjusting for maternal age, BMI, ethnicity, smoking, parity, gestational age at blood sampling, fetal sex, and gestational age at birth. The study protocol was pre-registered at the International Prospective Register of Systematic Reviews, CRD42016043496.
FINDINGS: We identified 2526 published reports, from which 36 cohorts met the inclusion criteria. The study authors for 15 of these cohorts agreed to participate, and five more unpublished datasets were added, giving a study population of 48 145 mother-child pairs after exclusions, of whom 1275 (3·1%) had subclinical hypothyroidism (increased thyroid stimulating hormone [TSH] with normal free thyroxine [FT4]) and 929 (2·2%) had isolated hypothyroxinaemia (decreased FT4 with normal TSH). Maternal subclinical hypothyroidism was associated with a higher risk of SGA than was euthyroidism (11·8% vs 10·0%; adjusted risk difference 2·43%, 95% CI 0·43 to 4·81; odds ratio [OR] 1·24, 1·04 to 1·48; p=0·015) and lower mean birthweight (mean difference -38 g, -61 to -15; p=0·0015), with a higher effect estimate for measurement in the third trimester than in the first or second. Isolated hypothyroxinaemia was associated with a lower risk of SGA than was euthyroidism (7·3% vs 10·0%, adjusted risk difference -2·91, -4·49 to -0·88; OR 0·70, 0·55 to 0·91; p=0·0073) and higher mean birthweight (mean difference 45 g, 18 to 73; p=0·0012). Each 1 SD increase in maternal TSH concentration was associated with a 6 g lower birthweight (-10 to -2; p=0·0030), with higher effect estimates in women who were thyroid peroxidase antibody positive than for women who were negative (pinteraction=0·10). Each 1 SD increase in FT4 concentration was associated with a 21 g lower birthweight (-25 to -17; p<0·0001), with a higher effect estimate for measurement in the third trimester than the first or second.
INTERPRETATION: Maternal subclinical hypothyroidism in pregnancy is associated with a higher risk of SGA and lower birthweight, whereas isolated hypothyroxinaemia is associated with lower risk of SGA and higher birthweight. There was an inverse, dose-response association of maternal TSH and FT4 (even within the normal range) with birthweight. These results advance our understanding of the complex relationships between maternal thyroid function and fetal outcomes, and they should prompt careful consideration of potential risks and benefits of levothyroxine therapy during pregnancy.
FUNDING: Netherlands Organization for Scientific Research (grant 401.16.020).
Copyright © 2020 Elsevier Ltd. All rights reserved.
Abstract/Text
CONTEXT: Previous studies suggested a potential link of maternal thyroid dysfunction with adverse neurocognitive outcomes and impaired development of internal organs in offspring.
OBJECTIVE: To review the association between maternal thyroid dysfunction and the risk of adverse outcomes in offspring.
DATA SOURCES: PubMed, EMBASE, and Cochrane Library.
STUDY SELECTIONS: Eligible studies reported the association between maternal thyroid hormone function and the risk of adverse outcomes in their children.
DATA EXTRACTION: Reviewers extracted data on study characteristics and results independently.
DATA SYNTHESIS: Estimates were pooled and reported as odds ratio (OR) with 95% confidence interval (CI). I2 tests were applied to assess the heterogeneity across studies.
RESULTS: We identified 29 eligible articles and found an association between maternal hyperthyroidism and attention deficit hyperactivity disorder (ADHD) (OR: 1.18, 95% CI: 1.04-1.34, I2 = 0%) and epilepsy (OR: 1.19, 95% CI: 1.08-1.31, I2 = 0%) in offspring; as well as an association of maternal hypothyroidism with increased risk of ADHD (OR: 1.14, 95% CI: 1.03-1.26, I2 = 25%), autism spectrum disorder (OR: 1.41, 95% CI: 1.05-1.90, I2 = 63%), and epilepsy (OR: 1.21, 95% CI: 1.06-1.39, I2 = 0%) in offspring.
CONCLUSION: Routine measurement and timely treatment on thyroid function should be considered for pregnant women.
© Endocrine Society 2020. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Abstract/Text
OBJECTIVE: To investigate the relationship between specific thyroid abnormalities in women during pregnancy and the subsequent neuropsychological development of their offspring.
METHODS: A systematic literature search of PubMed, Embase and Web of Science was conducted. Eligible studies were case-control or cohort study that explored this association with euthyroid thyroid abnormalities during pregnancy. The outcomes included intelligence scores and motor scores. Weighted mean differences (WMDs) and 95% confidence intervals (CIs) were calculated and heterogeneity was assessed with Cochrane Q chi-square test and I(2) statistics. A fixed-effects or random-effects model was used to pool the estimates according to the heterogeneity among the included studies.
RESULTS: Six studies, involving 4449 participants, were included. Children of women with thyroid abnormalities had mean intelligence score of 6.27 points and motor score of 5.99 points lower than that of children of euthyroid women. Subgroup analysis suggested that, children of women with hypothyroxinaemia, subclinical hypothyroidism and positive TPOAb had mean intelligence scores of 5.69 points, 8.76 points and 10.55 points, and mean motor scores of 4.19 points, 9.98 points and 9.03 points lower than those of the controls, respectively.
CONCLUSIONS: The thyroid abnormalities in pregnant women may adversely affect neuropsychological development of their offspring.
Abstract/Text
BACKGROUND: Rodents with gestational thyroid-hormone (TH) deficiencies and children with congenital hypothyroidism show abnormal hippocampal development. Given that the human hippocampus starts to develop early in gestation, we asked if children born to women with hypothyroidism during pregnancy also show hippocampal abnormalities and if this is related to the severity of maternal TH insufficiency and current memory functioning. We additionally sought to determine whether effects were more prominent in anterior or posterior hippocampal subsections given these support different memory functions and have different developmental trajectories. We hypothesized that these children would have smaller than normal hippocampal volumes than controls and show memory deficits on both standardized tests and indices of "everyday" memory functioning.
METHODS: We studied 54 children aged 9 to 12 years: 30 controls and 24 HYPO cases-offspring from women diagnosed with hypothyroidism prior to or during pregnancy and treated with l-thyroxine. All children received a thorough assessment of memory functions and an MRI scan. For each child, right and left hippocampi were manually traced, and volumes of right and left hippocampi and anterior and posterior segments were determined.
RESULTS: HYPO cases showed significantly smaller right and left hippocampal volumes than controls, particularly in right posterior and left anterior segments. In HYPO children, hippocampal volumes were negatively correlated with maternal third-trimester TSH levels and positively correlated with third-trimester fT4. HYPO cases scored significantly below controls on one objective and several subjective memory indices, and these were correlated with hippocampal volumes.
CONCLUSION: Early TH insufficiency from maternal hypothyroidism affects offspring hippocampal development and memory.
Abstract/Text
CONTEXT: Although maternal hypothyroxinemia is suggested to be related to various adverse consequences in a child's neurodevelopment, the underlying neurobiology is largely unknown.
OBJECTIVE: The objective of the study was to examine the relationship between maternal hypothyroxinemia in early pregnancy and children's nonverbal intelligence quotient (IQ). Furthermore, we explored whether global brain volumes, cortical thickness, and brain surface area differed between children exposed prenatally to hypothyroxinemia and healthy controls.
DESIGN AND SETTING: The study included a large population-based prospective birth cohort in The Netherlands.
PARTICIPANTS: A total of 3727 mother-child pairs with data on prenatal thyroid function at less than 18 weeks of gestation and nonverbal IQ at 6 years participated in the study. In 652 children, brain imaging was performed at 8 years of age.
MAIN MEASURES: Maternal hypothyroxinemia was defined as free T4 in the lowest 5% of the sample, whereas TSH was in the normal range. At 6 years, children's IQ was assessed using a Dutch test battery. Global brain volumetric measures, cortical thickness, and surface area were assessed using high-resolution structural magnetic resonance imaging.
RESULTS: The children of mothers with hypothyroxinemia in early pregnancy scored 4.3 points IQ lower than the children of mothers with normal thyroid status (95% confidence interval -6.68, -1.81; P = .001). After adjustment for multiple testing, we did not find any differences in brain volumetric measures, cortical thickness, and surface area between children exposed prenatally to hypothyroxinemia and controls.
CONCLUSIONS: Our findings confirm a large adverse effect of maternal hypothyroxinemia on children's nonverbal IQ at school age. However, we found no evidence that maternal hypothyroxinemia is associated with differences in brain morphology in school-age children.
Torie C Plowden, Enrique F Schisterman, Lindsey A Sjaarda, Shvetha M Zarek, Neil J Perkins, Robert Silver, Noya Galai, Alan H DeCherney, Sunni L Mumford
Subclinical Hypothyroidism and Thyroid Autoimmunity Are Not Associated With Fecundity, Pregnancy Loss, or Live Birth.
J Clin Endocrinol Metab. 2016 Jun;101(6):2358-65. doi: 10.1210/jc.2016-1049. Epub 2016 Mar 29.
Abstract/Text
CONTEXT: Prior studies examining associations between subclinical hypothyroidism and antithyroid antibodies with early pregnancy loss and live birth suggest mixed results and time to pregnancy (TTP) has not been studied in this patient population.
OBJECTIVE: This study sought to examine associations of prepregnancy TSH concentrations and thyroid autoimmunity with TTP, pregnancy loss, and live birth among women with proven fecundity and a history of pregnancy loss.
DESIGN AND SETTING: This was a prospective cohort study from a large, randomized controlled trial that took place at four medical centers in the United States.
PATIENTS OR OTHER PARTICIPANTS: Healthy women, ages 18-40 y, who were actively attempting to conceive and had one or two prior pregnancy losses and no history of infertility were eligible for the study.
INTERVENTION: There were no interventions.
MAIN OUTCOME MEASURE: TTP, pregnancy loss, and live birth.
RESULTS: Women with TSH ≥ 2.5 mIU/L did not have an increased risk of pregnancy loss (risk ratio, 1.07; 95% confidence interval [CI], 0.81-1.41) or a decrease in live birth rate (risk ratio, 0.97; 95% CI, 0.88-1.07) or TTP (fecundability odds ratio, 1.09; 95% CI, 0.90-1.31) compared with women with TSH <2.5 mIU/L after adjustment for age and body mass index. Similar findings were observed for women with thyroid autoimmunity and after additional adjustment for treatment assignment.
CONCLUSIONS: Among healthy fecund women with a history pregnancy loss, TSH levels ≥ 2.5 mIU/L or the presence of antithyroid antibodies were not associated with fecundity, pregnancy loss, or live birth. Thus, women with subclinical hypothyroidism or thyroid autoimmunity can be reassured that their chances of conceiving and achieving a live birth are likely unaffected by marginal thyroid dysfunction.
Brian M Casey, Elizabeth A Thom, Alan M Peaceman, Michael W Varner, Yoram Sorokin, Deborah G Hirtz, Uma M Reddy, Ronald J Wapner, John M Thorp, George Saade, Alan T N Tita, Dwight J Rouse, Baha Sibai, Jay D Iams, Brian M Mercer, Jorge Tolosa, Steve N Caritis, J Peter VanDorsten, Eunice Kennedy Shriver National Institute of Child Health and Human Development Maternal–Fetal Medicine Units Network
Treatment of Subclinical Hypothyroidism or Hypothyroxinemia in Pregnancy.
N Engl J Med. 2017 Mar 2;376(9):815-825. doi: 10.1056/NEJMoa1606205.
Abstract/Text
Background Subclinical thyroid disease during pregnancy may be associated with adverse outcomes, including a lower-than-normal IQ in offspring. It is unknown whether levothyroxine treatment of women who are identified as having subclinical hypothyroidism or hypothyroxinemia during pregnancy improves cognitive function in their children. Methods We screened women with a singleton pregnancy before 20 weeks of gestation for subclinical hypothyroidism, defined as a thyrotropin level of 4.00 mU or more per liter and a normal free thyroxine (T4) level (0.86 to 1.90 ng per deciliter [11 to 24 pmol per liter]), and for hypothyroxinemia, defined as a normal thyrotropin level (0.08 to 3.99 mU per liter) and a low free T4 level (<0.86 ng per deciliter). In separate trials for the two conditions, women were randomly assigned to receive levothyroxine or placebo. Thyroid function was assessed monthly, and the levothyroxine dose was adjusted to attain a normal thyrotropin or free T4 level (depending on the trial), with sham adjustments for placebo. Children underwent annual developmental and behavioral testing for 5 years. The primary outcome was the IQ score at 5 years of age (or at 3 years of age if the 5-year examination was missing) or death at an age of less than 3 years. Results A total of 677 women with subclinical hypothyroidism underwent randomization at a mean of 16.7 weeks of gestation, and 526 with hypothyroxinemia at a mean of 17.8 weeks of gestation. In the subclinical hypothyroidism trial, the median IQ score of the children was 97 (95% confidence interval [CI], 94 to 99) in the levothyroxine group and 94 (95% CI, 92 to 96) in the placebo group (P=0.71). In the hypothyroxinemia trial, the median IQ score was 94 (95% CI, 91 to 95) in the levothyroxine group and 91 (95% CI, 89 to 93) in the placebo group (P=0.30). In each trial, IQ scores were missing for 4% of the children. There were no significant between-group differences in either trial in any other neurocognitive or pregnancy outcomes or in the incidence of adverse events, which was low in both groups. Conclusions Treatment for subclinical hypothyroidism or hypothyroxinemia beginning between 8 and 20 weeks of gestation did not result in significantly better cognitive outcomes in children through 5 years of age than no treatment for those conditions. (Funded by the Eunice Kennedy Shriver National Institute of Child Health and Human Development and the National Institute of Neurological Disorders and Stroke; ClinicalTrials.gov number, NCT00388297 .).
Abstract/Text
BACKGROUND: The association between subclinical hypothyroidism (sHT) and cognitive impairment or risk of dementia is not well-defined, especially in the elderly, where the assessment of central nervous system function is challenging. The aim of this systematic review and meta-analysis was to evaluate the possible effect of sHT on cognitive decline and the risk of dementia.
METHODS: Cognitive function was the primary outcome, evaluated as composite endpoint of incidence or prevalence of dementia or difference of Mini Mental State Examination, Wechsler Adult Intelligence Scale, and Wechsler Memory Scale-Revised scores.
RESULTS: Thirteen studies were included in the meta-analysis. A significant risk of cognitive alteration was observed only in sHT individuals younger than age 75 years: composite endpoint odds ratio (OR) 1.56 (95% confidence interval [CI] 1.07-2.27, P = .02, I(2) = 82.5%), risk of dementia OR 1.81 (95% CI 1.43-2.28, P < .01, I(2) = 35%). Mean serum thyroid-stimulating hormone (TSH) levels and the OR of composite endpoint were positively correlated. No significant effect of sHT was found when considering all the studies as a whole: composite endpoint OR 1.26 (95% CI 0.96-1.66, P = .09, I(2) = 87.2%), risk of dementia OR 1.42 (95% CI, 0.97-2.07, P = .07, I(2) = 66.8%), Mini Mental State Examination mean difference -0.059 (95% CI -0.464 to 0.346 P = .78, I(2) = 51.8%).
CONCLUSIONS: This meta-analysis demonstrates a relationship between sHT and cognitive impairment only in individuals younger than 75 years of age and those with higher TSH concentrations. No correlation was found while considering all the studies as a whole. The lack of utilization of age-related serum TSH reference ranges and consequent potential misdiagnosis of sHT in older people may account for this.
Geanina Popoveniuc, Tanu Chandra, Anchal Sud, Meeta Sharma, Marc R Blackman, Kenneth D Burman, Mihriye Mete, Sameer Desale, Leonard Wartofsky
A diagnostic scoring system for myxedema coma.
Endocr Pract. 2014 Aug;20(8):808-17. doi: 10.4158/EP13460.OR.
Abstract/Text
OBJECTIVE: To develop diagnostic criteria for myxedema coma (MC), a decompensated state of extreme hypothyroidism with a high mortality rate if untreated, in order to facilitate its early recognition and treatment.
METHODS: The frequencies of characteristics associated with MC were assessed retrospectively in patients from our institutions in order to derive a semiquantitative diagnostic point scale that was further applied on selected patients whose data were retrieved from the literature. Logistic regression analysis was used to test the predictive power of the score. Receiver operating characteristic (ROC) curve analysis was performed to test the discriminative power of the score.
RESULTS: Of the 21 patients examined, 7 were reclassified as not having MC (non-MC), and they were used as controls. The scoring system included a composite of alterations of thermoregulatory, central nervous, cardiovascular, gastrointestinal, and metabolic systems, and presence or absence of a precipitating event. All 14 of our MC patients had a score of ≥60, whereas 6 of 7 non-MC patients had scores of 25 to 50. A total of 16 of 22 MC patients whose data were retrieved from the literature had a score ≥60, and 6 of 22 of these patients scored between 45 and 55. The odds ratio per each score unit increase as a continuum was 1.09 (95% confidence interval [CI], 1.01 to 1.16; P = .019); a score of 60 identified coma, with an odds ratio of 1.22. The area under the ROC curve was 0.88 (95% CI, 0.65 to 1.00), and the score of 60 had 100% sensitivity and 85.71% specificity.
CONCLUSION: A score ≥60 in the proposed scoring system is potentially diagnostic for MC, whereas scores between 45 and 59 could classify patients at risk for MC.
Mouhand F H Mohamed, Mohammed Danjuma, Mohammed Mohammed, Samreen Mohamed, Martin Siepmann, Kristian Barlinn, Salah Suwileh, Lina Abdalla, Dabia Al-Mohanadi, Juan Carlos Silva Godínez, Abdel-Naser Elzouki, Timo Siepmann
Myxedema Psychosis: Systematic Review and Pooled Analysis.
Neuropsychiatr Dis Treat. 2021;17:2713-2728. doi: 10.2147/NDT.S318651. Epub 2021 Aug 18.
Abstract/Text
Background and Objective: The term myxedema psychosis (MP) was introduced to describe the occurrence of psychotic symptoms in patients with untreated hypothyroidism, but the optimal assessment and treatment of this condition are unclear. We aimed to synthesize data from the literature to characterize the clinical presentation and management of MP.
Methods: We performed a systematic review according to the PRISMA (preferred reporting items for systematic reviews and meta-analyses) guidelines in PubMed (Medline), Embase, Google Scholar, and Cochrane databases, including observational studies, case series, and case reports published from 1/1/1980 to 31/12/2019 in the English language. Descriptive statistics along with univariate and multivariate analysis were used for data synthesis.
Results: Out of 1583 articles screened, 71 case reports met our inclusion criteria providing data on 75 MP cases. The median age at diagnosis was 42 years [32-56]. About 53% had no prior hypothyroidism diagnosis. Delusions occurred in 91%, with a predominance of persecutory ideas (84%), while hallucinations occurred in 78%. Physical symptoms and signs of hypothyroidism were absent in 37% and 26%, respectively. If symptoms occurred, nonspecific fatigue was seen most frequently (63%). The median thyroid-stimulating hormone value was 93 mIU/L [60-139]. Thyroid peroxidase antibodies were found positive in 75% (23/33) of reported cases. Creatinine kinase was reported abnormal in seven cases. Cranial imaging (CT or MRI) and electroencephalogram were normal in 89%, 75%, and 73% of the cases reported. The majority of patients were treated orally with thyroxine in combination with short-term antipsychotics. More than 90% of them showed complete recovery. Univariate analysis revealed a trend towards a shorter duration of psychosis with IV thyroid hormone therapy (p= 0.0502), but the effect was not consistent in a multivariate analysis.
Conclusion: While we identified a substantial lack of published research on MP, our pooled analysis of case observations suggests that the condition presents a broad spectrum of psychiatric and physical symptoms lending support to the value of screening for thyroid dysfunction in patients with first-ever psychosis.
Prospero Registration Number: CRD42020160310.
© 2021 Mohamed et al.
Abstract/Text
Myxedema Madness is a rare but easily treatable cause of psychosis. Since Myxedema Madness was first described the question of a specific psychopathological symptom complex caused by severe hypothyroidism was raised in the literature. The present review of 52 published cases indicates that there are no specific somatic and psychopathological findings to diagnose a myxedema psychosis. It is diagnosed through the measurement of thyroid stimulating hormone and treated by application of L-thyroxine. Due to its excellent prognosis, myxedema madness should always be considered a differential diagnosis in new onset psychosis.
Copyright © 2021. Published by Elsevier Inc.
Abstract/Text
CONTEXT: Longitudinal studies of risk factors for hypothyroidism are required to inform debate regarding the TSH reference range. There are limited longitudinal data on the predictive value of thyroid antibodies measured by automated immunoassay (as opposed to semiquantitative methods).
METHODS: We measured TSH, free T(4), thyroid peroxidase antibodies (TPOAbs), and thyroglobulin antibodies (TgAbs) using the Immulite platform on sera from 1184 participants in the 1981 and 1994 Busselton Health Surveys. Outcome measures at follow-up were hypothyroidism, defined as TSH greater than 4.0 mU/liter or on thyroxine treatment; and overt hypothyroidism, defined as TSH above 10.0 mU/liter or on thyroxine treatment. Receiver-operator characteristic analysis was used to determine optimal cutoffs for baseline TSH, TPOAbs, and TgAbs as predictors of hypothyroidism.
RESULTS: At 13 yr follow-up, 110 subjects (84 women) had hypothyroidism, of whom 42 (38 women) had overt hypothyroidism. Optimal cutoffs for predicting hypothyroidism were baseline TSH above 2.5 mU/liter, TPOAbs above 29 kIU/liter, and TgAbs above 22 kIU/liter, compared with reference range upper limits of 4.0 mU/liter, 35 kIU/liter, and 55 kIU/liter, respectively. In women with positive thyroid antibodies (TPOAbs or TgAbs), the prevalence of hypothyroidism at follow-up (with 95% confidence intervals) was 12.0% (3.0-21.0%) when baseline TSH was 2.5 mU/liter or less, 55.2% (37.1-73.3%) for TSH between 2.5 and 4.0 mU/liter, and 85.7% (74.1-97.3%) for TSH above 4.0 mU/liter.
CONCLUSIONS: The use of TSH cutoffs of 2.5 and 4.0 mU/liter, combined with thyroid antibodies, provides a clinically useful estimate of the long-term risk of hypothyroidism.
Abstract/Text
BACKGROUND: Complex bidirectional relationships have been described between body weight, thyroid function, and risk of thyroid disorders, including thyroid autoimmunity. We used a life-course approach to examine the potential association of childhood or adult body weight with the risk of thyroid autoimmunity and other thyroid disorders at age 60-64 years in a large population-based birth cohort study.
METHODS: In the UK Medical Research Council 1946 British Birth Cohort study, at age 60-64 years, 1277 women and 1185 men (78% of the target sample) responded to a postal questionnaire, which included questions on thyroid disease and thyroid medication. Circulating antithyroid peroxidase antibodies, free T4, and TSH concentrations were measured in 1057 women and 997 men at a subsequent clinic visit. Birth weight was recorded, and height and weight were measured at ages 2, 4, 6, 7, 11, 15 years and also repeatedly in adulthood.
RESULTS: At age 60-64 years, 10.9% of women (139 of 1277) and 2.3% of men (27 of 1185) reported they were taking T4, and 11.5% of women (122 of 1057) and 3.3% of men (33 of 997) had positive anti-TPO antibodies (>100 IU/mL), consistent with thyroid autoimmunity. Among women, both T4 use and positive anti-TPO antibodies at age 60-64 years were positively associated with childhood body weight, childhood overweight, and adult body mass index. Childhood weight gain between 0 and 14 years of age was positively associated with later T4 use (odds ratio 1.21, 95% confidence interval 1.03-1.42) and positive anti-TPO antibodies (1.21, 1.00-1.47). Women who were overweight or obese at age 14 years (127 of 972) had a higher risk of later positive anti-TPO antibodies (2.05, 1.12-3.76). In men and women without any thyroid disorders, serum free T4 concentrations were inversely associated with concurrent body mass index (P = .002).
CONCLUSIONS: Childhood weight gain and childhood overweight conferred an increased susceptibility to later hypothyroidism and thyroid autoimmunity, particularly in women.
Giorgio Radetti, Mara Maselli, Fabio Buzi, Andrea Corrias, Alessandro Mussa, Paola Cambiaso, Mariacarolina Salerno, Marco Cappa, Michela Baiocchi, Roberto Gastaldi, Luigi Minerba, Sandro Loche
The natural history of the normal/mild elevated TSH serum levels in children and adolescents with Hashimoto's thyroiditis and isolated hyperthyrotropinaemia: a 3-year follow-up.
Clin Endocrinol (Oxf). 2012 Mar;76(3):394-8. doi: 10.1111/j.1365-2265.2011.04251.x.
Abstract/Text
OBJECTIVE: The natural history of Hashimoto's thyroiditis (HT) and isolated hyperthyrotropinaemia (IH) is not well defined. We therefore studied the natural course of patients with HT and IH and looked for possible prognostic factors.
DESIGN: This is retrospective cross-sectional study.
PATIENTS: Three hundred and twenty-three patients with HT (88 boys and 235 girls) and 59 with IH (30 boys and 29 girls), mean age 9·9 ± 3·8 years were included in the study. When first examined, 236 of the children with HT had a normal TSH (G0) and in 87, it was elevated but <100% of the upper limit (G1). All IH subjects had elevated TSH. Potential risk factors for thyroid failure were evaluated after 3 years and included the presence or familiarity for endocrine/autoimmune diseases, premature birth, signs and symptoms of hypothyroidism, TSH levels, antithyroid antibodies and thyroid volume.
RESULTS: HT: Of those with HT, 170 G0 patients remained stable, 31 moved to G1 and 35 to G2 (hypothyroidism). Thirty-six G1 children moved to G0, 17 remained stable and 34 moved to G2. Of patients with IH: 23 normalized, 28 remained stable and eight became overtly hypothyroid. In patients with HT, the presence of coeliac disease, elevated TSH and thyroid peroxidase antibodies (TPOAb) increased the risk of developing hypothyroidism by 4·0-, 3·4- and 3·5-fold, respectively. The increase in TSH levels during follow-up was strongly predictive of the development of hypothyroidism. In patients with IH, no predictive factor could be identified.
CONCLUSIONS: Coeliac disease, elevated TSH and TPOAb at presentation and a progressive increase in TSH are predictive factors for thyroid failure in HT patients.
© 2012 Blackwell Publishing Ltd.
Abstract/Text
CONTEXT: Use of a single set of thyroid function tests to define subclinical hypothyroidism may lead to misclassification over time and could influence findings from longitudinal studies.
OBJECTIVE: We assessed the risks of coronary heart disease (CHD), heart failure (HF), and cardiovascular (CV) death in older adults with persistent subclinical hypothyroidism.
DESIGN, SETTING, AND PARTICIPANTS: The study included 679 subclinically hypothyroid and 4184 euthyroid U.S. individuals at least 65 yr old enrolled in the Cardiovascular Health Study and not taking thyroid preparations.
MAIN OUTCOME MEASURE: We measured the 10-yr risk of incident CHD, HF, and CV death from persistent subclinical hypothyroidism, overall and stratified by degree of TSH elevation (4.5-6.9, 7.0-9.9, and 10.0-19.9 mU/liter).
RESULTS: There was no association between persistent subclinical hypothyroidism and incident CHD [hazard ratio (HR), 1.12; 95% confidence interval (CI), 0.93-1.36], HF (HR, 1.05; 95% CI, 0.97-1.27), or CV death (HR, 1.07; 95% CI, 0.87-1.31) in adjusted analyses in which subclinical hypothyroidism was modeled as a time-varying exposure using up to four serial thyroid function tests. When subclinical hypothyroidism was stratified by degree of TSH elevation, no significant associations were found in any stratum. Findings were similar in fixed exposure analyses in which only participants with testing 2 yr apart were considered, with no association between persistent or transient subclinical hypothyroidism and incident CHD, HF, or CV death.
CONCLUSIONS: Our data do not support increased risk of CHD, HF, or CV death in older adults with persistent subclinical hypothyroidism.
Abstract/Text
Thyroid hormone plays an important role in cardiac function. Low levels of serum triiodothyronine (T3) due to nonthyroidal illness syndrome may have adverse effects in heart failure (HF). This study was designed to assess the ability of T3 to predict in-hospital outcomes in patients with acute HF. In total, 137 patients without thyroid disease or treatment with drugs which affect TH levels, who were hospitalized with acute HF were prospectively enrolled and studied. TH levels were tested upon hospital admission, and outcomes were compared between patients with low (<2.3 pg/ml) and normal (≥2.3 pg/ml) free T3 levels as well as between those with low (<0.6 ng/ml) and normal (≥0.6 ng/ml) total T3 levels. Low free T3 correlated with an increased length of stay in the hospital (median 11 vs 7 days, p <0.001) and higher rates of intensive care unit admission (31.8% vs 16.9%, p = 0.047), with a trend toward increased need for invasive mechanical ventilation (9.0% vs 1.4%, p = 0.056). Low total T3 correlated with an increased length of stay in the hospital (median 11 vs 7 days, p <0.001) and increased need for invasive mechanical ventilation (9.8% vs 1.3%, p = 0.045). In conclusion, low T3 predicts worse hospital outcomes in patients with acute HF and can be useful in the risk stratification of these patients.
Copyright © 2016 Elsevier Inc. All rights reserved.
Abstract/Text
OBJECTIVE: We aimed to evaluate immune-related adverse events occurring in clinical trials of anti-programmed cell death 1 (PD-1) drugs, compared with control treatments, including chemotherapy, targeted drugs, or placebo. Further we compared the occurrence of immune -related events in patients treated with different anti-PD-1 drugs.
DATA SOURCES: Randomized controlled trial (RCT) data were sourced from PubMed, Embase, and the Cochrane Central Register of Controlled Trials combined with https://clinicaltrials.gov.
METHODS: Randomized controlled trial of anti-PD-1 drugs compared with control treatments published between January 1, 1970 and March 1,2019, were searched and data on trial patient characteristics, and adverse events extracted, reviewed, and subjected to meta-analysis.
RESULTS: Eighteen Randomized controlled trials were included in our study. The Randomized controlled trials compared nivolumab (n = 12), pembrolizumab (n = 6), with chemotherapy (n = 13), targeted drugs (n = 2), or placebo (n = 3). Compared with the control group, the risk of any immune-related adverse events in patients treated with anti-PD-1 drugs was increased (RR, 2.65; 95% confidence interval, 1.84-3.83; P < 0.00001). Of the immune-related adverse events, the risk rates of pneumonitis (risk ratio, 2.10; 95% CI, 0.85-5.18), colitis (2.96;1.62-5.38), hypophysitis(4.79;1.54-14.89), hypothyroidism(7.87;5.36-11.57), hyperthyroidism (7.03;4.35-11.34), rash (1.58;0.98-2.54), pruritus (2.28; 1.38-3.76), and hepatitis (9.31;2.18-39.85) were increased by anti-PD-1 drugs. Further, the risk of immune-related adverse events was similar for patients treated with pembrolizumab and nivolumab (P = 0.14).
CONCLUSIONS: In addition to previously reported organ-specific immune-related adverse events, we found that the risk of hyperthyroidism was also increased, in anit-PD-1-treated patients, relative to control treatments. The risk of total immune-related adverse events, was similar for pembrolizumab and nivolumab.
Abstract/Text
Background: Although combination therapy with immune checkpoint inhibitors (ICIs) provides a promising efficacy in multiple cancers, their use is facing challenges for a high incidence of adverse effects. This meta-analysis was conducted to compare the risks of organ-specific immune-related adverse events (IRAEs) associated with ICI monotherapy versus combination therapy among cancer patients.
Methods: Electronic databases were systematically searched to include eligible randomized controlled trials (RCTs). Any-grade and 3-5 grade IRAEs (colitis, pneumonitis, hepatitis, hypothyroidism, hyperthyroidism, and hypophysitis) were extracted for meta-analysis. Two reviewers independently assessed the methodological quality. The RevMan 5.3.5 software was used for meta-analysis.
Results: A total of 10 studies involving 8 RCTs with 2716 patients were included in this study. The most common any-grade adverse event was colitis (14.5%), followed by hypothyroidism (13.8%), hepatitis (10.4%), hypophysitis (10.0%), hyperthyroidism (9.3%), and pneumonitis (4.6%). Meta-analysis showed that ICI combination therapy significantly increased the risks of any-grade IRAEs in colitis [relative risk (RR), 3.56; 95% confidence interval (CI), 1.56-8.12; p < 0.05], pneumonitis (RR, 2.31; 95% CI, 1.54-3.45; p < 0.05), hepatitis (RR, 2.54; 95% CI, 1.65-3.91; p < 0.05), hypothyroidism (RR, 2.17; 95% CI, 1.71-2.76; p < 0.05), hyperthyroidism (RR, 3.13; 95% CI, 2.08-4.70; p < 0.05), and hypophysitis (RR, 3.54; 95% CI, 2.07-6.07; p < 0.05) compared with ICI monotherapy, as well as 3-5 grade IRAEs in colitis (RR, 2.50; 95% CI, 1.62-3.86; p < 0.05), pneumonitis (RR, 1.99; 95% CI, 1.00-3.93; p = 0.05), and hepatitis (RR, 2.70; 95% CI, 1.29-5.63; p < 0.05).
Conclusions: This meta-analysis demonstrated that, compared with ICI monotherapy, patients receiving ICI combination therapy significantly increased organ-specific IRAEs in colitis, hypothyroidism, hepatitis, hypophysitis, hyperthyroidism, and pneumonitis. The incidence and severity of organ-specific IRAEs were drug and dose independent.
Copyright © 2020 Da, Teng, Wang, Zaguirre, Liu, Qi and Song.
Abstract/Text
BACKGROUND: Immune checkpoint inhibitors (ICIs) emerged as the preferred therapy in advanced lung cancer, understanding the treatment- and immune-related adverse events of these drugs is of great significance for clinical practice.
MATERIALS AND METHODS: PubMed, Embase, Cochrane library and major conference proceedings were systematically searched for all randomized controlled trials (RCTs) in lung cancer using PD-1/PD-L1/CTLA-4 inhibitors. The outcomes included treatment-related adverse events (TRAEs) and several organ specific immune-related adverse events (IRAEs).
RESULTS: 24 RCTs involving 14,256 patients were included. There was a significant difference for ICI therapy in the incidence of any grade of TRAEs (RR: 0.90; 95%CI: 0.84-0.95; P=0.001) and a lower frequency of grade 3-5 of TRAEs (RR: 0.65; 95%CI: 0.51-0.82; P<0.001). Patients treated with ICI therapy in non-small-cell lung cancer (NSCLC) were less reported TRAEs than in small cell lung cancer (SCLC). A lower risk of TRAEs was favored by anti-PD-1 inhibitors over anti-PD-L1 antibodies and anti-CTLA-4 drugs. The most common organ specific IRAE was hypothyroidism that occurred 8.7%. The incidence of pneumonitis and hepatitis reached 4.5% and 4.0% respectively. Compared with patients treated in control arms, those treated with ICI drugs were at higher risk for each organ specific adverse event including colitis, hepatitis, pneumonitis, hypothyroidism and hypophysitis.
CONCLUSIONS: ICI therapy was safer than chemotherapy, especially ICI monotherapy such as anti-PD-1 antibodies in NSCLC. Compared with standard treatments, ICI drugs increased the risk of organ-specific IRAEs, although the overall incidence remained low.
© 2020 The Author(s).
Abstract/Text
OBJECTIVE: The main aim of this study was to systematically evaluate the efficacy and safety of inhibitors of programmed cell death receptor 1 (PD-1) and its ligand, programmed cell death ligand-1 (PD-L1), in the treatment of advanced non-small cell lung cancer (NSCLC).
METHODS: Randomized controlled trials assessing the efficacy of PD-1/PD-L1 inhibitors relative to platinum-based chemotherapy for advanced NSCLC in PubMed, EMBASE, and Cochrane libraries from 2015 to 2020 were searched, along with review of studies at American Society of Clinical Oncology (ASCO) and European society for Medical Oncology (ESMO). Pooled hazard ratios (HR) for progression-free survival (PFS) and overall survival (OS) and odds ratios (OR) for adverse events (AE) were calculated using STATA and Revman software.
RESULTS: PD-1/PD-L1 inhibitors alone or combined with chemotherapy significantly improved OS (HR = 0.82, 95% CI:0.74-0.91, P = 0.01 or HR = 0.74, 95% CI:0.67-0.82, P = 0.001). PD-1/PD-L1 inhibitors alone did not benefit PFS (HR = 0.99, 95% CI: 0.89-1.10, P = 0.892), while combination therapy led to prolonged PFS (HR = 0.61, 95% CI: 0.56-0.67, P < 0.001). Subgroup analysis showed that in NSCLC with PD-L1 ≥ 50%, treatment with PD-1/PD-L1 inhibitors alone significantly improved both PFS and OS. In patients subjected to the combined treatment regimen, we observed significant differences in PFS among groups stratified by PD-L1 expression (p < 0.001), immune drug type (p = 0.029), gender (p = 0.014) and liver metastasis (p = 0.035) and OS among groups stratified by immune drug type (p < 0.001), gender (P = 0.001) and smoking status (P = 0.041). Safety analysis showed that combination therapy increased chemotherapy-induced adverse events (AE), while PD-1/PD-L1 inhibitors alone were associated with a lower incidence of any grade of treatment-related AEs (TRAE). A higher incidence of Grade 3-5 TRAEs and hypothyroidism was observed with PD-1 inhibitors than PD-L1 inhibitors.
CONCLUSIONS: First-line treatment of advanced NSCLC with immune monotherapy or immunochemotherapy confers a greater survival benefit than chemotherapy alone. Combination of chemotherapy with PD-1/PD-L1 inhibitors leads to an increase in adverse events, and PD-1 inhibitors offer enhanced survival benefits and fewer adverse events than PD-L1 inhibitors. Remarkably, female patients undergoing combination therapy had longer overall survival than male patients.
Copyright © 2020 The Author(s). Published by Elsevier Ltd.. All rights reserved.
Abstract/Text
Background: Thyroid dysfunction is common for cancer patients receiving PD-1/PD-L1 inhibitor therapies. To clarify the incidence risk of thyroid dysfunction would be important for guiding anti-PD-1 and anti-PD-L1 immunotherapy. Therefore, the updated meta-analysis was conducted to evaluate the incidence risk of thyroid dysfunction caused by PD-1/PD-L1 inhibitors.
Methods: PD-1/PD-L1 inhibitor related clinical trials were collected by a systematic search of the PubMed. Some relevant studies were identified by a manual search. The incidence risk of all grades and grades 3-5 was analyzed and evaluated by random effect model. The Newcastle Ottawa Scale was used for the quality assessment of all clinical trials.
Results: Forty-three clinical trials were collected. Compared with chemotherapy, the risk of hypothyroidism of all grades was significantly higher (OR=7.15, 95%CI:[4.85, 10.55], I2 = 40%, Z=9.91(P <0.00001)) in PD-1/PD-L1 group. Similar results could also be noted, when the control group was placebo or CTLA-4. When PD-1/PD-L1 was combined with other treatments for cancer patients, the risk of hypothyroidism of all grades was also significantly increased. Similar to the analysis results of hypothyroidism, PD-1/PD-L1 inhibitors played the same role in increasing the risk of hyperthyroidism and thyroiditis. Few significant analysis results was noted, when the risk of thyroid dysfunction of grades 3-5 was assessed.
Conclusion: Whether used alone or in combination with other anti-tumor drugs, PD-1/PD-L1 inhibitors increased the risk of thyroid dysfunction, especially for hypothyroidism. Furthermore, PD-1/PD-L1 was better than chemotherapy and CTLA-4 in increasing the risk of thyroid dysfunction.
Copyright © 2021 Tian, Li, Liu, Li, Song, Zheng, Gao, Wen, Su and Sun.
Abstract/Text
BACKGROUND: Over recent years, immune checkpoint inhibitors (ICIs) have changed the clinical management and prognosis for most cancers. However, data on older patients in clinical trials are scarce.
OBJECTIVE: We performed a systematic review and pooled analysis of real-life studies to explore the efficacy and toxicity of ICIs in unselected older individuals in multiple tumor settings treated outside of clinical trials.
PATIENTS AND METHODS: We searched articles, including prospective cohort studies, observational or retrospective series, or expanded access programs, published in English from 2010 to October 2020 in PubMed, MEDLINE, the Cochrane Library, and EMBASE. We excluded hematological malignancies.
RESULTS: Forty-eight studies met the predefined criteria and were eligible for inclusion in the systematic review. We included 5524 patients. The pooled median overall survival was 8.9 (95% CI 7.3-10.5) and 14.3 (95% CI 11.3-17) months for non-small cell lung cancer (NSCLC: n = 17 studies; 95% in pretreated setting) and melanoma, respectively (n = 3). Median progression-free survival was 3.2 (95% CI 2.7-3.8) and 7.9 (95% CI 6.05-9.78) months for NSCLC and melanoma cohorts. Pooled rates of Grade 1-5 hepatitis, pneumonitis, hypothyroidism, and diarrhea were 5.3% (95% CI 3.7-7.6), 6% (95% CI 3.8-9.4), 8.3% (95% CI 5.4-12.5) and 7.6% (95% CI 5.7-10), respectively.
CONCLUSIONS: Our findings suggest that ICIs could be safely administered in older individuals with comparable survival outcomes with respect to younger individuals. Future studies should include some form of geriatric assessment to improve patient stratification.
© 2021. The Author(s), under exclusive licence to Springer Nature Switzerland AG.
Abstract/Text
Background: This study investigated the relationship strength between hypothyroidism and cardiovascular and renal outcomes in diabetic patients. Methods: The electronic databases PubMed, EmBase, and Cochrane library were screened for relevant studies published before November 2018. The outcomes included major cardiovascular events (MACEs), all-cause mortality, cardiac death, stroke, diabetic nephropathy (DN), diabetic retinopathy (DR), and chronic kidney disease (CKD). The pooled results for all outcomes were calculated using random-effects models. Results: A total of eight studies met the inclusion criteria. The summary results indicated that hypothyroidism was not associated with the risk of MACEs (OR:1.21; 95%CI:0.68-2.16; P = 0.514), all-cause mortality (OR:1.27; 95%CI:0.93-1.74; P = 0.136), cardiac death (OR:1.16; 95%CI:0.89-1.52; P = 0.271), stroke (OR:0.96; 95%CI: 0.49-1.88; P = 0.915), and DN (OR:1.71; 95%CI:0.37-7.90; P = 0.490). There was a significant association between hypothyroidism and the risk of DR (OR:1.73; 95%CI:1.08-2.77; P = 0.023) and CKD (OR:1.22; 95%CI:1.10-1.36; P < 0.001). Conclusions: These findings indicate that diabetic patients with hypothyroidism have an increased risk of DR and CKD. Additional large-scale prospective studies should be carried out to verify the prognosis of patients with diabetes and hypothyroidism.
Copyright © 2020 Zhang, Feng, Kang, Guo, Ti, Hao, Gao and Gao.
Abstract/Text
CONTEXT: The evidence of whether hypothyroidism increases mortality in the elderly population is currently inconsistent and conflicting.
OBJECTIVE: The objective of this meta-analysis is to determine the impact of hypothyroidism on mortality in the elderly population.
DATA SOURCES: PubMed, Embase, Cochrane Library, Scopus, and Web of Science databases were searched from inception until May 10, 2019.
STUDY SELECTION: Studies evaluating the association between hypothyroidism and all-cause and/or cardiovascular mortality in the elderly population (ages ≥ 60 years) were eligible.
DATA EXTRACTION: Two reviewers independently extracted data and assessed the quality of the studies. Relative risk (RR) was retrieved for synthesis. A random-effects model for meta-analyses was used.
DATA SYNTHESIS: A total of 27 cohort studies with 1 114 638 participants met the inclusion criteria. Overall, patients with hypothyroidism experienced a higher risk of all-cause mortality than those with euthyroidism (pooled RR = 1.26, 95% CI: 1.15-1.37); meanwhile, no significant difference in cardiovascular mortality was found between patients with hypothyroidism and those with euthyroidism (pooled RR = 1.10, 95% CI: 0.84-1.43). Subgroup analyses revealed that overt hypothyroidism (pooled RR = 1.10, 95% CI: 1.01-1.20) rather than subclinical hypothyroidism (pooled RR = 1.14, 95% CI: 0.92-1.41) was associated with increased all-cause mortality. The heterogeneity primarily originated from different study designs (prospective and retrospective) and geographic locations (Europe, North America, Asia, and Oceania).
CONCLUSIONS: Based on the current evidence, hypothyroidism is significantly associated with increased all-cause mortality instead of cardiovascular mortality among the elderly. We observed considerable heterogeneity, so caution is needed when interpreting the results. Further prospective, large-scale, high-quality studies are warranted to confirm these findings.
© Endocrine Society 2019. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Abstract/Text
Background: Fibrotic diseases have an unclear etiology and poor prognosis. Fluctuations in thyroid function may play a role in the development of fibrosis, but evidence is fragmented and inconclusive. This systematic review and meta-analysis aimed to investigate the association of thyroid function with fibrotic diseases of the liver, heart, and lung in humans. Methods: We searched PubMed, Medline Ovid, Embase Ovid, and Web-of-Science for studies published from inception to 14 June 2019, to identify observational studies that investigated the association of thyroid function with fibrosis of the liver, heart, and lung in humans. Study quality was evaluated by the Newcastle-Ottawa Scale. The Mantel-Haenszel method was used to pool the odds ratios (ORs) of studies investigating the association of hypothyroidism with liver fibrosis. Results: Of the 2196 identified articles, 18 studies were included in the systematic review, of which 11 studies reported on liver fibrosis, 4 on myocardial fibrosis, and 3 on pulmonary fibrosis. The population sample size ranged from 36 to 7259 subjects, with median mean age 51 years (range, 36-69) and median percentage of women 53 (range, 17-100). The risk of bias of studies was low to moderate to high. Higher serum thyrotropin and lower thyroid hormone levels were generally associated with higher likelihood of fibrosis. Compared with euthyroidism, overt and subclinical hypothyroidism was associated with a higher likelihood of fibrosis in the liver (six of seven studies), heart (three of three studies), and lung (three of three studies). Based on the results of the seven studies included in the meta-analysis, overt and subclinical hypothyroidism was associated with an increased risk of liver fibrosis (pooled OR, 2.81; 95% confidence interval [CI], 1.74-4.53; heterogeneity, I2 31.4%; pooled OR, 2.12; CI, 1.45-3.12; heterogeneity, I2 0%; respectively), without evidence of publication bias. Conclusions: This study suggests that low thyroid function is associated with increased likelihood of chronic fibrotic diseases of the liver, heart, and lung. However, the evidence is mainly based on cross-sectional data. Prospective studies and randomized clinical trials are needed to investigate the potential efficacy of thyroid hormone and its analogs on the occurrence and progression of fibrosis.
Juliana Muñoz-Ortiz, Maria Camila Sierra-Cote, Estefanía Zapata-Bravo, Laura Valenzuela-Vallejo, Maria Alejandra Marin-Noriega, Pilar Uribe-Reina, Juan Pablo Terreros-Dorado, Marcela Gómez-Suarez, Karla Arteaga-Rivera, Alejandra de-la-Torre
Prevalence of hyperthyroidism, hypothyroidism, and euthyroidism in thyroid eye disease: a systematic review of the literature.
Syst Rev. 2020 Sep 1;9(1):201. doi: 10.1186/s13643-020-01459-7. Epub 2020 Sep 1.
Abstract/Text
BACKGROUND: Thyroid eye disease is an autoimmune disorder of the orbital retrobulbar tissue commonly associated with dysthyroid status. The most frequent condition is hyperthyroidism, although it is also present in hypothyroid and euthyroid patients. The prevalence of thyroid conditions in patients with thyroid eye disease had been previously evaluated; however, there is no consensus on a global prevalence. The study aims to estimate the prevalence of hyperthyroidism, hypothyroidism, and euthyroidism in patients with TED, through a systematic review of literature.
METHODS: We conducted a systematic review of the literature following the PRISMA guidelines, in MEDLINE, COCHRANE, EMBASE, Science Direct, and LILACS databases. Inclusion criteria were primary studies of patients with a diagnosis of thyroid eye disease made by an ophthalmologist or with diagnosis criteria, with measurement of thyroid function (TSH, T3, and free T4), and diagnosis of the primary thyroid condition. A quality assessment was made through the Joanna Briggs Institute Quality tools. Finally, we extracted relevant details about the design, the results, and the prevalence of thyroid disorders in thyroid eye disease.
RESULTS: The initial search revealed 916 studies, of which finally thirteen met inclusion criteria. Six studies were performed in Europe (Germany, Wales, and Spain), five in Asia (Iran, South Korea, Japan, and Singapore), one in North America (USA), and one in Africa (Ghana). The global prevalence, in patients of thyroid eye disease, was 10.36% for hypothyroidism, 7.9% for euthyroidism, and 86.2% for hyperthyroidism.
CONCLUSIONS: Professionals should be aware that thyroid eye disease can be present in patients with a normal thyroid function. The assessment for these patients is based on orbital images; serum TSH, T3, and free T4; antibody levels as thyrotropin receptor antibodies; and thyroperoxidase levels. Additionally, we want to encourage research in this field in other regions of the world such as Latin America.
SYSTEMATIC REVIEW REGISTRATION: PROSPERO ID CRD42020107167.
Abstract/Text
Thyroid disease is a very common condition that influences the entire human body, including cognitive function and mental health. As a result, thyroid disease has been associated with multiple neuropsychiatric conditions. However, the relationship between thyroid dysfunction and suicide is still controversial. We conducted a systematic review and meta-analysis to describe the association of thyroid function with suicidal behavior in adults. We searched four data bases (MEDLINE, EMBASE, PsycINFO, and Scopus) from their inception to 20 July 2018. Studies that reported mean values and standard deviation (SD) of thyroid hormone levels [Thyroid-stimulating hormone (TSH), free thyroxine (FT4), free triiodothyronine (FT3), total thyroxine (TT4), and total triiodothyronine (TT3)] in patients with suicidal behavior compared with controls were included in this meta-analysis. The abstracts and papers retrieved with our search strategies were reviewed independently and in duplicate by four reviewers for assessment of inclusion criteria and data extraction, as well as for evaluation of risk of bias. Random-effects models were used in this meta-analysis to establish the mean difference on thyroid function tests between groups. Overall, 2278 articles were identified, and 13 studies met the inclusion criteria. These studies involved 2807 participants, including 826 participants identified with suicidal behavior. We found that patients with suicide behavior had lower levels of FT3 (-0.20 pg/mL; p = 0.02) and TT4 (-0.23 µg/dL; p = 0.045) compared to controls. We found no differences in either TSH, FT4, or TT3 levels among groups. With our search strategy, we did not identify studies with a comparison of overt/subclinical thyroid disease prevalence between patients with and without suicide behavior. The studies included in this meta-analysis had a low-to-moderate risk of bias. In the available literature, the evidence regarding the association of thyroid disorders and suicidal behavior is limited. We found that patients with suicidal behavior have significantly lower mean FT3 and TT4 levels when compared to patients without suicidal behavior. The clinical implications and pathophysiologic mechanisms of these differences remain unknown and further research is needed.
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OBJECTIVE: There is an increasing body of literature on the impact of COVID-19 on the pituitary-thyroid axis. Therefore, we conducted a systematic review to assess the prevalence of hypothyroidism in patients with COVID-19.
METHODS: A literature review was conducted using LitCOVID for study selection in PubMed and MEDLINE till May 2021. All relevant original articles evaluating thyroid dysfunction were included and information regarding the prevalence of hypothyroid disease in COVID-19 was retrieved from the eligible articles.
RESULTS: Out of 32 articles, six articles qualified for the final analysis which included 1160 patients. There was significant heterogeneity among the included articles. Most of the patients had lower mean triiodothyronine (T3) and normal or low thyroid-stimulating hormone (TSH). Increased TSH ranged from 5.1% to 8% while low T3 was present in up to 28% of the patients. In these studies, the prevalence of altered thyroid hormones was significantly more in COVID-19 patients as compared to control groups. A positive correlation between low mean T3 and clinical severity of COVID-19 was reported.
CONCLUSION: This systematic review reveals a significant proportion of hypothyroidism associated with COVID-19. Therefore, routine assessment of thyroid function is warranted in hospitalized COVID-19 patients.
Abstract/Text
Importance: Hypothyroidism is considered a cause of or a strong risk factor for depression, but recent studies provide conflicting evidence regarding the existence and the extent of the association. It is also unclear whether the link is largely due to subsyndromal depression or holds true for clinical depression.
Objective: To estimate the association of hypothyroidism and clinical depression in the general population.
Data Sources: PubMed, PsycINFO, and Embase databases were searched from inception until May 2020 for studies on the association of hypothyroidism and clinical depression.
Study Selection: Two reviewers independently selected epidemiologic and population-based studies that provided laboratory or International Statistical Classification of Diseases and Related Health Problems diagnoses of hypothyroidism and diagnoses of depression according to operationalized criteria (eg, Diagnostic and Statistical Manual of Mental Disorders or International Statistical Classification of Diseases and Related Health Problems) or cutoffs in established rating scales.
Data Extraction and Synthesis: Two reviewers independently extracted data and evaluated studies based on the Newcastle-Ottawa Scale. Summary odds ratios (OR) were calculated in random-effects meta-analyses.
Main Outcomes and Measures: Prespecified coprimary outcomes were the association of clinical depression with either hypothyroidism or autoimmunity.
Results: Of 4350 articles screened, 25 studies were selected for meta-analysis, including 348 014 participants. Hypothyroidism and clinical depression were associated (OR, 1.30 [95% CI, 1.08-1.57]), while the OR for autoimmunity was inconclusive (1.24 [95% CI, 0.89-1.74]). Subgroup analyses revealed a stronger association with overt than with subclinical hypothyroidism, with ORs of 1.77 (95% CI, 1.13-2.77) and 1.13 (95% CI, 1.01-1.28), respectively. Sensitivity analyses resulted in more conservative estimates. In a post hoc analysis, the association was confirmed in female individuals (OR, 1.48 [95% CI, 1.18-1.85]) but not in male individuals (OR, 0.71 [95% CI, 0.40-1.25]).
Conclusions and Relevance: In this systematic review and meta-analysis, the effect size for the association between hypothyroidism and clinical depression was considerably lower than previously assumed, and the modest association was possibly restricted to overt hypothyroidism and female individuals. Autoimmunity alone may not be the driving factor in this comorbidity.
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PURPOSE: Clinical studies have investigated the prevalence of gestational diabetes mellitus (GDM) in women with subclinical hypothyroidism (SCH). While some studies demonstrate a clear association, others do not. It is possible this may be due to varied diagnostic criteria for SCH and the presence of thyroid antibodies (TA). We conducted a meta-analysis, separating patients diagnosed with SCH using a diagnostic cut-off <4.0 mIU/L from those diagnosed using a cut-off >4.0 mIU/L and determined the association with GDM and factored TA status into our analysis.
METHODS: A computerised search of five databases including PubMed, Embase, Cochrane Library, Web of Science and CINAHL returned 787 records. Two independent reviewers assessed abstracts and full texts against pre-specified inclusion and exclusion criteria. Ten cohort studies were included in the final analysis. The diagnostic criteria for SCH and incidence of GDM were extracted from each study. Study quality and risk of bias was assessed by two reviewers.
RESULTS: TSH levels <4.0 mIU/L for SCH diagnosis was not associated with GDM unless patients were TA positive. Studies that used a diagnostic cut-off >4.0 mIU/L saw a significant increase in the odds of GDM, regardless of TA status (OR = 1.60, 95% CI 1.33-1.93).
CONCLUSIONS: Women with TSH levels >4.0 mIU/L have an increased odds of GDM regardless of TA status but at TSH levels <4.0 mIU/L, GDM is dependent on TA status. The use of TSH levels to identify pregnancies at risk of GDM is a novel concept that warrants exploration.
© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.
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Alterations in metabolic parameters have been associated with an increased risk of dementia, among which thyroid function has gained great importance in Alzheimer's disease (AD) pathology in recent years. However, it remains unclear whether thyroid dysfunctions could influence and contribute to the beginning and/or progression of AD or if it results from AD. This systematic review was conducted to examine the association between thyroid hormone (TH) levels and AD. Medline, ISI Web of Science, EMBASE, Cochrane library, Scopus, Scielo, and LILACS were searched, from January 2010 to March 2020. A total of 17 articles were selected. The studies reported alterations in TH and circadian rhythm in AD patients. Behavior, cognition, cerebral blood flow, and glucose consumption were correlated with TH deficits in AD patients. Whether thyroid dysfunctions and AD have a cause-effect relationship was inconclusive, however, the literature was able to provide enough data to corroborate a relationship between TH and AD. Although further studies are needed in this field, the current systematic review provides information that could help future investigations.
© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.
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CONTEXT: The association of non-thyroidal illness syndrome (NTIS) and hypothyroidism with the prognosis in ischemic heart disease (IHD) population is inconclusive.
OBJECTIVE: We aimed to evaluate the influence of NTIS and hypothyroidism on all-cause mortality and major adverse cardiac events (MACE) in IHD population.
DATA SOURCES: We searched PubMed, EMBASE, Scopus, Web of Science, and Cochrane Library from inception through February 17, 2020.
STUDY SELECTION: Original articles enrolling IHD patients, comparing all-cause mortality and MACE of NTIS and hypothyroidism with those of euthyroidism, and providing sufficient information for meta-analysis were considered eligible.
DATA EXTRACTION: Relevant information and numerical data were extracted for methodological assessment and meta-analysis.
DATA SYNTHESIS: Twenty-three studies were included. The IHD population with NTIS was associated with higher risk of all-cause mortality (hazard ratio [HR] = 2.61; 95% confidence interval [CI] = 1.89-3.59) and MACE (HR = 2.22; 95% CI = 1.71-2.89) than that without. In addition, the IHD population with hypothyroidism was also associated with higher risk of all-cause mortality (HR = 1.47; 95% CI = 1.10-1.97) and MACE (HR = 1.53; 95% CI = 1.19-1.97) than that without. In the subgroup analysis, the acute coronary syndrome (ACS) subpopulation with NTIS was associated with higher risk of all-cause mortality (HR = 3.30; 95% CI = 2.43-4.48) and MACE (HR = 2.19; 95% CI = 1.45-3.30). The ACS subpopulation with hypothyroidism was also associated with higher risk of all-cause mortality (HR = 1.67; 95% CI = 1.17-2.39).
CONCLUSIONS: The IHD population with concomitant NTIS or hypothyroidism was associated with higher risk of all-cause mortality and MACE. Future research is required to provide evidence of the causal relationship and to elucidate whether normalizing thyroid function parameters can improve prognosis.
© Endocrine Society 2020. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
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OBJECTIVES: To determine whether thyroxine treatment is effective in patients with symptoms of hypothyroidism but with thyroid function tests within the reference range, and to investigate the effect of thyroxine treatment on psychological and physical wellbeing in healthy participants.
DESIGN: Randomised double blind placebo controlled crossover trial.
SETTING: Outpatient clinic in a general hospital. Participants: 25 patients with symptoms of hypothyroidism who had thyroid function tests within the reference range, and 19 controls. Methods: Participants were given thyroxine 100 microgram or placebo to take once a day for 12 weeks. Washout period was six weeks. They were then given the other to take once a day for 12 weeks. All participants were assessed physiologically and psychologically at baseline and on completion of each phase.
MAIN OUTCOME MEASURES: Thyroid function tests, measures of cognitive function and of psychological and physical wellbeing.
RESULTS: 22 patients and 19 healthy controls completed the study. At baseline, patients' scores on 9 out of 15 psychological measures were impaired when compared with controls. Patients showed a significantly greater response to placebo than controls in 3 out of 15 psychological measures. Healthy participants had significantly lower scores for vitality when taking thyroxine compared to placebo (mean (SD) 60 (17) v 73 (16), P<0.01). However, patients' scores from psychological tests when taking thyroxine were no different from those when taking placebo except for a poorer performance on one visual reproduction test when taking thyroxine. Serum concentrations of free thyroxine increased and those of thyroid stimulating hormone decreased in patients and controls while they were taking thyroxine, confirming compliance with treatment. Although serum concentrations of free triiodothyronine increased in patients and controls taking thyroxine, the difference between the response to placebo and to thyroxine was significant only in the controls.
CONCLUSIONS: Thyroxine was no more effective than placebo in improving cognitive function and psychological wellbeing in patients with symptoms of hypothyroidism but thyroid function tests within the reference range. Thyroxine did not improve cognitive function and psychological wellbeing in healthy participants.
Martin Feller, Marieke Snel, Elisavet Moutzouri, Douglas C Bauer, Maria de Montmollin, Drahomir Aujesky, Ian Ford, Jacobijn Gussekloo, Patricia M Kearney, Simon Mooijaart, Terry Quinn, David Stott, Rudi Westendorp, Nicolas Rodondi, Olaf M Dekkers
Association of Thyroid Hormone Therapy With Quality of Life and Thyroid-Related Symptoms in Patients With Subclinical Hypothyroidism: A Systematic Review and Meta-analysis.
JAMA. 2018 Oct 2;320(13):1349-1359. doi: 10.1001/jama.2018.13770.
Abstract/Text
Importance: The benefit of thyroid hormone therapy for subclinical hypothyroidism is uncertain. New evidence from recent large randomized clinical trials warrants an update of previous meta-analyses.
Objective: To conduct a meta-analysis of the association of thyroid hormone therapy with quality of life and thyroid-related symptoms in adults with subclinical hypothyroidism.
Data Sources: PubMed, EMBASE, ClinicalTrials.gov, Web of Science, Cochrane Library, CENTRAL, Emcare, and Academic Search Premier from inception until July 4, 2018.
Study Selection: Randomized clinical trials that compared thyroid hormone therapy with placebo or no therapy in nonpregnant adults with subclinical hypothyroidism were eligible. Two reviewers independently evaluated eligibility based on titles and abstracts of all retrieved studies. Studies not excluded in this first step were independently assessed for inclusion after full-text evaluation by 2 reviewers.
Data Extraction and Synthesis: Two independent reviewers extracted data, assessed risk of bias (Cochrane risk-of-bias tool), and evaluated the quality of evidence (GRADE tool). For synthesis, differences in clinical scores were transformed (eg, quality of life) into standardized mean differences (SMDs; positive values indicate benefit of thyroid hormone therapy; 0.2, 0.5, and 0.8 correspond to small, moderate, and large effects, respectively). Random-effects models for meta-analyses were applied.
Main Outcomes and Measures: General quality of life and thyroid-related symptoms after a minimum follow-up of 3 months.
Results: Overall, 21 of 3088 initially identified publications met the inclusion criteria, with 2192 adults randomized. After treatment (range, 3-18 months), thyroid hormone therapy was associated with lowering the mean thyrotropin value into the normal reference range compared with placebo (range, 0.5-3.7 mIU/L vs 4.6 to 14.7 mIU/L) but was not associated with benefit regarding general quality of life (n = 796; SMD, -0.11; 95% CI, -0.25 to 0.03; I2=66.7%) or thyroid-related symptoms (n = 858; SMD, 0.01; 95% CI, -0.12 to 0.14; I2=0.0%). Overall, risk of bias was low and the quality of evidence assessed with the GRADE tool was judged moderate to high.
Conclusions and Relevance: Among nonpregnant adults with subclinical hypothyroidism, the use of thyroid hormone therapy was not associated with improvements in general quality of life or thyroid-related symptoms. These findings do not support the routine use of thyroid hormone therapy in adults with subclinical hypothyroidism.
Abstract/Text
BACKGROUND: Data suggest symptoms of hypothyroidism persist in 5-10% of levothyroxine (L-T4)-treated hypothyroid patients with normal serum thyrotrophin (TSH). The use of L-T4 + liothyronine (L-T3) combination therapy in such patients is controversial. The ETA nominated a task force to review the topic and formulate guidelines in this area.
METHODS: Task force members developed a list of relevant topics. Recommendations on each topic are based on a systematic literature search, discussions within the task force, and comments from the European Thyroid Association (ETA) membership at large.
RESULTS: SUGGESTED EXPLANATIONS FOR PERSISTING SYMPTOMS INCLUDE: awareness of a chronic disease, presence of associated autoimmune diseases, thyroid autoimmunity per se, and inadequacy of L-T4 treatment to restore physiological thyroxine (T4) and triiodothyronine (T3) concentrations in serum and tissues. There is insufficient evidence that L-T4 + L-T3 combination therapy is better than L-T4 monotherapy, and it is recommended that L-T4 monotherapy remains the standard treatment of hypothyroidism. L-T4 + L-T3 combination therapy might be considered as an experimental approach in compliant L-T4-treated hypothyroid patients who have persistent complaints despite serum TSH values within the reference range, provided they have previously received support to deal with the chronic nature of their disease, and associated autoimmune diseases have been excluded. Treatment should only be instituted by accredited internists/endocrinologists, and discontinued if no improvement is experienced after 3 months. It is suggested to start combination therapy in an L-T4/L-T3 dose ratio between 13:1 and 20:1 by weight (L-T4 once daily, and the daily L-T3 dose in two doses). Currently available combined preparations all have an L-T4/L-T3 dose ratio of less than 13:1, and are not recommended. Close monitoring is indicated, aiming not only to normalize serum TSH and free T4 but also normal serum free T4/free T3 ratios. Suggestions are made for further research.
CONCLUSION: L-T4 + L-T3 combination therapy should be considered solely as an experimental treatment modality. The present guidelines are offered to enhance its safety and to counter its indiscriminate use.
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OBJECTIVE: To assess whether adding liothyronine (LT3) to levothyroxine (LT4) monotherapy normalizes serum thyrotropin (TSH) and thyroxine (T4) concentrations in children with congenital hypothyroidism and central resistance to thyroid hormone.
STUDY DESIGN: We retrospectively studied 12 patients with congenital hypothyroidism and central resistance to thyroid hormone (6 treated with LT3+LT4 combined therapy and 6 treated with LT4 monotherapy). In patients receiving combined therapy, we compared serum concentrations of TSH, T4, and triiodothyronine before and after addition of LT3. We used repeated measures analysis to compare thyroid function in participants receiving combined therapy vs monotherapy, while accounting for age and intrasubject correlation.
RESULTS: In patients receiving combined therapy, the addition of LT3 was associated with normalization of mean TSH (9.2 vs 4.5 mIU/L, P = .002), a lower proportion of TSH values greater than 10 mIU/L (35% vs 8%, P = .03), and a decrease in mean serum T4 by 23 ± 9% (P < .001). Compared with patients receiving LT4 monotherapy, patients receiving combined therapy had lower mean TSH (8.5 ± 0.9 vs 4.3 ± 0.4, P < .001), lower odds of TSH elevation greater than 10 mIU/L (OR 0.20, 95% CI 0.10-0.41, P < .001), and lower odds of T4 elevation (OR 0.21, 95% CI 0.04-1.09, P = .06). LT3 treatment did not increase serum T3 levels significantly.
CONCLUSION: The addition of LT3 to LT4 monotherapy facilitates normalization of both serum TSH and T4 in patients with congenital hypothyroidism and central resistance to thyroid hormone. Larger prospective studies are needed to confirm these findings and to determine the effect of combined therapy on neurodevelopmental outcomes.
Copyright © 2016 Elsevier Inc. All rights reserved.
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CONTEXT: In patients with coexisting iron-deficiency anemia and subclinical hypothyroidism, anemia does not adequately respond to oral iron therapy.
OBJECTIVE: We studied whether iron-deficiency anemia might indicate treatment of subclinical hypothyroidism.
DESIGN: PATIENTS were assigned to a control or experimental group: 240 mg/d oral iron alone (iron group) or 240 mg/d oral iron plus 75 microg/d levothyroxine (iron/levothyroxine group). Levels of hemoglobin, hematocrit, red blood cell count, serum iron levels, ferritin, total iron-binding capacity, TSH, and free T(4) were measured before and after treatment.
SETTING: The study was conducted at a university hospital outpatient clinic.
PATIENTS: Fifty-one patients with coexisting iron-deficiency anemia and subclinical hypothyroidism participated in the study.
INTERVENTION: PATIENTS were treated as described above in either the iron group or the iron/levothyroxine group.
MAIN OUTCOME MEASURE: A clinically satisfactory increase in hemoglobin was regarded as successful.
RESULTS: Mean hemoglobin levels increased by 0.4 g/dl in the iron group [95% confidence interval (CI) 0.2-0.7, P = 0.001], whereas it increased by a mean of 1.9 g/dl in the iron/levothyroxine group (95% CI 1.5-2.3, P < 0.0001). The increase in serum iron was greater in the iron/levothyroxine group by a mean of 47.6 microg/dl (95% CI 34.5-60.6, P < 0.0001). Increases in hemoglobin, red blood cells, hematocrit, and serum ferritin levels after treatment were statistically significantly greater in the iron/levothyroxine group (P < 0.0001). Starting hemoglobin and increase in hemoglobin were negatively correlated in the iron/levothyroxine group (r = -0.531, P = 0.006).
CONCLUSIONS: Subclinical hypothyroidism should be treated in iron-deficiency anemia patients when both conditions coexist. This would provide a desired therapeutic response to oral iron replacement and prevent ineffective iron therapy.
Abstract/Text
BACKGROUND: Hypothyroidism is treated with oral levothyroxine. Some patients fail to attain adequate control because of poor compliance. Delaying breakfast to take levothyroxine on an empty stomach can decrease adherence to hypothyroidism treatment. The objective of this study was to evaluate whether administering levothyroxine with breakfast can maintain thyrotropin (TSH) levels in the therapeutic range, without major clinical changes.
METHODS: A prospective, randomized, open-label, crossover study was conducted to compare usual levothyroxine administration while in a fasting state with administration during breakfast. From September 2008 to April 2009, 45 patients with primary hypothyroidism who received levothyroxine were recruited. The patients completed 180 days of the protocol and were randomized to 90 days of each levothyroxine administration regimen (while fasting or with breakfast). Clinical and biochemical analyses were performed at baseline and on days 45, 90, 135, and 180. The primary outcome was TSH level.
RESULTS: Forty-two patients completed the protocol. The TSH level was higher for levothyroxine administration with breakfast than while fasting (2.89 vs. 1.9 mIU/L, p=0.028). Uncontrolled hypothyroidism (TSH ≥3.5 mIU/L) occurred regardless of the type of levothyroxine administration (p=0.26). No risk factors were identified for TSH elevation.
CONCLUSIONS: Levothyroxine administration with breakfast could be an alternative regimen for patients who have adherence difficulties due to the need for delaying intake, and is more likely to cause variability in the TSH level, meaning the patient should be followed more closely. For patients in whom a specific serum TSH goal is important, taking levothyroxine while fasting is recommended.
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PURPOSE: To compare the effects of l-thyroxine (L-T4) administration before breakfast and administration at bedtime on hypothyroidism.
METHODS: The PubMed, EMBASE, Cochrane Library, Web of Science, China National Knowledge Infrastructure (CNKI) and Wanfang databases were searched to identify relevant articles. All prospective or randomized controlled studies (RCTs) comparing L-T4 administration before breakfast to the administration at bedtime in patients with hypothyroidism were included in the analysis.
RESULTS: Initially, 2884 articles were retrieved from the databases, and 10 articles were included in the quantitative analysis. The effect of L-T4 administration before breakfast compared with administration at bedtime had no statistically significant association with hormone thyrotropin (TSH) (Standardized mean differences [SMD] = 0.09, 95% confidence intervals (CI): -0.12, 0.30; P = .39), or free triiodothyronine (FT3) (SMD=-0.19, 95% CI: -0.53, 0.15; P = .28) in patients with hypothyroidism. However, the result of FT4 level was favourable for L-T4 bedtime administration group (SMD=-0.27, 95% CI: -0.52, -0.02; P = .03).
CONCLUSION: Our meta-analysis revealed that L-T4 administration at bedtime is as effective as administration before breakfast for patients with hypothyroidism. Taking L-T4 at bedtime may be an attractive option for patients with hypothyroidism.
© 2020 John Wiley & Sons Ltd.
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OBJECTIVES: To evaluate the electrodiagnostic evidence of peripheral nerve dysfunction in patients with hypothyroidism before and after hormone replacement treatment.
MATERIALS AND METHODS: Forty patients aged above 18 years diagnosed with hypothyroidism were included in our study. Patients with FT4 levels below 11.6 pmol/l and TSH levels above 4.2 IU/ml were accepted as hypothyroidic. Electrodiagnostic evaluation was performed at the onset of the study and after 3 months. Electrodiagnostic evaluation included motor and sensory nerve conduction studies, and F wave.
RESULTS: The differences between pre- and post-treatment FT4, FT3 and TSH values were found to be statistically significant. At the onset, electrophysiological evaluation revealed carpal tunnel syndrome in 15 patients and polyneuropathy in seven patients; whereas 18 patients were found normal in these respects. After treatment, the electrodiagnostic evaluation revealed that 35 patients were normal, while only two patients had carpal tunnel syndrome and three patients had polyneuropathy. The differences between before and after treatment values of median motor distal latency and amplitude, median sensorial nerve conduction velocity, tibial motor nerve conduction velocity and sural sensory nerve conduction velocity were found to be statistically significant.
CONCLUSION: The results of the control evaluation after treatment demonstrated that the findings related to entrapment neuropathy and polyneuropathy in hypothyroid patients can be reversible in a period of 3 months if appropriate hormone replacement treatment can be obtained. Especially in the treatment of entrapment neuropathy in hypothyroidism, the chance of medical treatment must be given to patients before considering surgical treatment.
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BACKGROUND: Severe acquired hypothyroidism often results in significant height deficit due to rapid bone age advancement following treatment. Whether gradual correction of hypothyroidism and/or adjunctive growth-promoting therapies (GPTs) augment final adult height (FAH) is controversial.
OBJECTIVE: To investigate time to euthyroidism, pace of bone age advancement (deltaBA/deltaCA), and impact of GPTs on FAH.
METHODS AND PATIENTS: Retrospective review of 21 children (10.1 +/- 3.0 years) with profound hypothyroidism.
RESULTS: Baseline bone age standard deviation score (SDS) was -4.1 +/- 1.8, whereas height SDS was -3.0 +/- 1.1. Average time to euthyroidism was 9.7 months (2.3-33.7 months). Average deltaBA/deltaCA was 2.3 +/- 0.9. Six of 13 patients at FAH received GPTs. No correlation was found between time to euthyroidism and rate of skeletal maturation. No difference in height outcome was seen between those who received GPTs and those who did not.
CONCLUSIONS: Neither time to euthyroidism nor use of GPTs significantly affected height potential in our patients.
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PURPOSE OF REVIEW: In recent years, there has been an increasing focus on thyroid function in obese children. There is controversy concerning whether the changes in the levels of thyroid hormones and thyroid-stimulating hormone (thyrotropin - TSH) in obesity are causes or consequences of weight status and whether these subtle differences merit treatment with thyroxine. This review aimed to study the prevalence of disturbed thyroid hormone and TSH values in childhood obesity and the underlying pathophysiologic mechanisms linking obesity to thyroid function.
RECENT FINDINGS: In the past 18 months, four studies demonstrated moderate elevation of TSH concentrations in 10-23% of obese children, which was associated with normal or slightly elevated thyroxine and triiodothyronine values. Two studies reported ultrasonographic hypoechogenicity of the thyroid in obese children with hyperthyrotropinemia, which was not caused by autoimmune thyroiditis; therefore, the authors hypothesized a link to chronic inflammation in obesity. Weight loss led to a normalization of elevated TSH levels in two studies. The adipokine leptin is the most promising link between obesity and hyperthyrotropinemia since leptin stimulates the hypothalamic-pituitary-thyroid.
SUMMARY: The elevated TSH levels in obesity seem a consequence rather than a cause of obesity. Therefore, treatment of hyperthyrotropinemia with thyroxine seems unnecessary in obese children.
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CONTEXT: Subclinical hypothyroidism (SCH) and cognitive dysfunction are both common in the elderly and have been linked. It is important to determine whether T4 replacement therapy in SCH confers cognitive benefit.
OBJECTIVE: Our objective was to determine whether administration of T4 replacement to achieve biochemical euthyroidism in subjects with SCH improves cognitive function.
DESIGN AND SETTING: We conducted a double-blind placebo-controlled randomized controlled trial in the context of United Kingdom primary care.
PATIENTS: Ninety-four subjects aged 65 yr and over (57 females, 37 males) with SCH were recruited from a population of 147 identified by screening.
INTERVENTION: T4 or placebo was given at an initial dosage of one tablet of either placebo or 25 microg T4 per day for 12 months. Thyroid function tests were performed at 8-weekly intervals with dosage adjusted in one-tablet increments to achieve TSH within the reference range for subjects in treatment arm. Fifty-two subjects received T4 (31 females, 21 males; mean age 73.5 yr, range 65-94 yr); 42 subjects received placebo (26 females, 16 males; mean age 74.2 yr, 66-84 yr).
MAIN OUTCOME MEASURES: Mini-Mental State Examination, Middlesex Elderly Assessment of Mental State (covering orientation, learning, memory, numeracy, perception, attention, and language skills), and Trail-Making A and B were administered.
RESULTS: Eighty-two percent and 84% in the T4 group achieved euthyroidism at 6- and 12-month intervals, respectively. Cognitive function scores at baseline and 6 and 12 months were as follows: Mini-Mental State Examination T4 group, 28.26, 28.9, and 28.28, and placebo group, 28.17, 27.82, and 28.25 [not significant (NS)]; Middlesex Elderly Assessment of Mental State T4 group, 11.72, 11.67, and 11.78, and placebo group, 11.21, 11.47, and 11.44 (NS); Trail-Making A T4 group, 45.72, 47.65, and 44.52, and placebo group, 50.29, 49.00, and 46.97 (NS); and Trail-Making B T4 group, 110.57, 106.61, and 96.67, and placebo group, 131.46, 119.13, and 108.38 (NS). Linear mixed-model analysis demonstrated no significant changes in any of the measures of cognitive function over time and no between-group difference in cognitive scores at 6 and 12 months.
CONCLUSIONS: This RCT provides no evidence for treating elderly subjects with SCH with T4 replacement therapy to improve cognitive function.
Abstract/Text
BACKGROUND Subclinical hypothyroidism (SCH) has been associated with ischemic heart disease (IHD); however, it is unknown whether treatment of SCH with levothyroxine sodium will reduce the risk of IHD. The aim of this study was to investigate the association between levothyroxine treatment of SCH with IHD morbidity and mortality. METHODS We used the United Kingdom General Practitioner Research Database to identify individuals with new SCH (serum thyrotropin levels of 5.01-10.0 mIU/L and normal free thyroxine levels) recorded during 2001 with outcomes analyzed until March 2009. All analyses were performed separately for younger (40-70 years) and older (>70 years) individuals. Hazard ratios (HRs) for IHD events (fatal and nonfatal) were calculated after adjustment for conventional IHD risk factors, baseline serum thyrotropin levels, and initiation of levothyroxine treatment as a time-dependent covariate. RESULTS Subclinical hypothyroidism was identified in 3093 younger and 1642 older individuals. For a median follow-up period of 7.6 years, 52.8% and 49.9% of younger and older patients with SCH were treated with levothyroxine, respectively. There were 68 incident IHD events in 1634 younger patients treated with levothyroxine (4.2%) vs 97 IHD events in 1459 untreated individuals (6.6%) (multivariate-adjusted HR, 0.61; 95% CI, 0.39-0.95). In contrast, in the older group there were 104 events in 819 treated patients (12.7%) vs 88 events in 823 untreated individuals (10.7%) (HR, 0.99; 95% CI, 0.59-1.33). CONCLUSIONS Treatment of SCH with levothyroxine was associated with fewer IHD events in younger individuals, but this was not evident in older people. An appropriately powered randomized controlled trial of levothyroxine in SCH examining vascular outcomes is now warranted.
Abstract/Text
BACKGROUND: Subclinical hypothyroidism is associated with a number of cardiovascular risk factors, yet only limited data exist on long-term outcome of levothyroxine treatment of this condition with respect to hard end-points. The aim of this retrospective cohort study was to determine effects of levothyroxine treatment on myocardial infarction (MI), cardiovascular death and all-cause mortality, in patients with subclinical hypothyroidism.
METHODS AND RESULTS: Primary care patients aged 18 years and older that underwent thyroid function tests between 2000 and 2009 were enrolled. Participants were identified by individual-level linkage of nationwide registers. Patients with subclinical hypothyroidism at baseline were included in the study. Exclusion criteria included a history of thyroid disease, related medication or medication affecting thyroid function. The total cohort comprised 628,953 patients of which 12,212 (1.9%) had subclinical hypothyroidism (mean age 55.2 [SD ± 18.8] years; 79.8% female). Within the first six months 2,483 (20.3%) patients claimed a prescription for levothyroxine. During a median follow-up of 5.0 (IQR: 5.2) years, 358 MI's and 1,566 (12.8%) deaths were observed. Out of these, 766 of the deaths were cardiovascular related. No beneficial effects were found in levothyroxine treated patients on MI (IRR 1.08 [95% CI: 0.81 to 1.44]), cardiovascular death (IRR 1.02 [95% CI: 0.83 to 1.25]) or all-cause mortality (IRR 1.03 [95% CI: 0.90 to 1.19]), except in patients under the age of 65 years (IRR 0.63 [95% CI: 0.40 to 0.99]).
CONCLUSION: Levothyroxine substitution in subclinical hypothyroid patients does not indicate an association with lower mortality or decreased risk of MI.
Abstract/Text
CONTEXT: Subclinical hypothyroidism is a common condition that may lead to impaired cardiac function.
OBJECTIVE: This study sought to examine the effects of levothyroxine treatment in patients with subclinical hypothyroidism and heart disease.
DESIGN: This was a register-based historical cohort study.
SETTING AND PARTICIPANTS: The study was composed of Danish primary care patients and hospital outpatients age 18 years and older with established heart disease who were diagnosed with subclinical hypothyroidism in 1997-2011. Patients were stratified according to whether they claimed a subsequent prescription of levothyroxine. Event rates and incidence rate ratios (IRR) were calculated by use of time-dependent multivariable Poisson regression models.
MAIN OUTCOME MEASURES: Measures included all-cause mortality and major adverse cardiac events (MACEs), defined as cardiovascular death, fatal or nonfatal myocardial infaction and stroke, and all-cause hospital admissions.
RESULTS: Of 61 611 patients with a diagnosis of cardiac disease having their first time thyroid function testing, 1192 patients with subclinical hypothyroidism (mean age 73.6 [SD ± 13.3] y, 63.8% female) were included, of whom 136 (11.4%) were treated with levothyroxine. During a median follow-up time of 5.6 y (interquartile range, 6.5 y), 694 (58.2%) patients died. Patients treated with levothyroxine displayed no significantly increased risk of all-cause mortality (adjusted IRR, 1.17; 95% confidence interval [CI], 0.90-1.52), MACE (adjusted IRR, 1.08; 95% CI, 0.80-1.45), or hospital admission (adjusted IRR, 0.94; 95% CI, 0.71-1.24), when compared with patients not treated with levothyroxine.
CONCLUSION: Levothyroxine treatment in patients with subclinical hypothyroidism and heart disease was not associated with a significant benefit nor risk of all-cause mortality, MACE, or hospital admission in this large real-world cohort study.
Lea Wildisen, Cinzia Del Giovane, Elisavet Moutzouri, Shanthi Beglinger, Lamprini Syrogiannouli, Tinh-Hai Collet, Anne R Cappola, Bjørn O Åsvold, Stephan J L Bakker, Bu B Yeap, Osvaldo P Almeida, Graziano Ceresini, Robin P F Dullaart, Luigi Ferrucci, Hans Grabe, J Wouter Jukema, Matthias Nauck, Stella Trompet, Henry Völzke, Rudi Westendorp, Jacobijn Gussekloo, Stefan Klöppel, Drahomir Aujesky, Douglas Bauer, Robin Peeters, Martin Feller, Nicolas Rodondi
An individual participant data analysis of prospective cohort studies on the association between subclinical thyroid dysfunction and depressive symptoms.
Sci Rep. 2020 Nov 5;10(1):19111. doi: 10.1038/s41598-020-75776-1. Epub 2020 Nov 5.
Abstract/Text
In subclinical hypothyroidism, the presence of depressive symptoms is often a reason for starting levothyroxine treatment. However, data are conflicting on the association between subclinical thyroid dysfunction and depressive symptoms. We aimed to examine the association between subclinical thyroid dysfunction and depressive symptoms in all prospective cohorts with relevant data available. We performed a systematic review of the literature from Medline, Embase, Cumulative Index to Nursing and Allied Health Literature, and the Cochrane Library from inception to 10th May 2019. We included prospective cohorts with data on thyroid status at baseline and depressive symptoms during follow-up. The primary outcome was depressive symptoms measured at first available follow-up, expressed on the Beck's Depression Inventory (BDI) scale (range 0-63, higher values indicate more depressive symptoms, minimal clinically important difference: 5 points). We performed a two-stage individual participant data (IPD) analysis comparing participants with subclinical hypo- or hyperthyroidism versus euthyroidism, adjusting for depressive symptoms at baseline, age, sex, education, and income (PROSPERO CRD42018091627). Six cohorts met the inclusion criteria, with IPD on 23,038 participants. Their mean age was 60 years, 65% were female, 21,025 were euthyroid, 1342 had subclinical hypothyroidism and 671 subclinical hyperthyroidism. At first available follow-up [mean 8.2 (± 4.3) years], BDI scores did not differ between participants with subclinical hypothyroidism (mean difference = 0.29, 95% confidence interval = - 0.17 to 0.76, I2 = 15.6) or subclinical hyperthyroidism (- 0.10, 95% confidence interval = - 0.67 to 0.48, I2 = 3.2) compared to euthyroidism. This systematic review and IPD analysis of six prospective cohort studies found no clinically relevant association between subclinical thyroid dysfunction at baseline and depressive symptoms during follow-up. The results were robust in all sensitivity and subgroup analyses. Our results are in contrast with the traditional notion that subclinical thyroid dysfunction, and subclinical hypothyroidism in particular, is associated with depressive symptoms. Consequently, our results do not support the practice of prescribing levothyroxine in patients with subclinical hypothyroidism to reduce the risk of developing depressive symptoms.
Abstract/Text
The goal of this study was to review relevant randomized controlled trials in order to determine the clinical efficacy of levothyroxine in the treatment of overt or subclinical hypothyroidism. Using appropriate keywords, we identified relevant studies using PubMed, the Cochrane library, and Embase. Key pertinent sources in the literature were also reviewed, and all articles published through December 2019 were considered for inclusion. For each study, we assessed odds ratios (ORs), mean difference (MD), and 95% confidence interval (95%CI) to assess and synthesize outcomes. We included 25 studies with totally 1,735 patients in the meta-analysis. In the patients with hypothyroidism, compared with L-T4, L-T4 plus L-T3 significantly decreased TSH levels and increased FT3 levels. Compared with placebo, L-T4 significantly increased FT4 levels and decreased TSH levels. In patients with subclinical hypothyroidism, compared with placebo, L-T4 significantly decreased SBP, TSH, T3 and TC and increased FT3 and FT4.
Abstract/Text
Fetal goitrous hypothyroidism is a rare condition associated with important obstetrical, neonatal complications, and neurodevelopmental impairments. Prenatal treatment remains controversial, and the risk to benefit ratio must be accurately assessed and considered for individualized management. The objective of this review was to evaluate the feasibility, safety, and effectiveness of the conservative in utero treatment of fetal goitrous hypothyroidism. In total, 25 reports that met our inclusion criteria were selected and the management of 38 cases was analyzed. Prenatal diagnosis consisted mainly of ultrasonographic findings. Fetal thyroid status was assessed by cordocentesis. Prenatal treatment varied widely in terms of levothyroxine (LT4) route of administration, dosage, number of injections, and frequency. Although different regimens and routes of administration were proposed, they seem to have similar results regarding fetal goiter reduction and thyroid status at birth. At birth, most babies had hypothyroidism, but the long-term follow-up indicated a normal psycho-neuromotor development. Our data confirm the feasibility of conservative treatment with LT4 for fetal goitrous hypothyroidism. Further studies are needed to determine the optimal management of this disorder.
Copyright: © Nemescu et al.
Abstract/Text
BACKGROUND/AIM: Thyroid dysfunction, both hypo- and hyperthyroidism, has been associated with cardiovascular disease. The aim of this study was to evaluate the association between thyroid dysfunction and atherosclerosis measured mostly by carotid intima-media thickness, as well as discuss whether L-T4 replacement is able to reverse or slow down the progression of atherosclerosis.
MATERIALS AND METHODS: The review was conducted according the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. We performed on PubMed a literature search from May 2004 to January 2020, using the search terms 'subclinical hypothyroidism' or 'thyroid disorders' and 'carotid artery', 'carotid intima-media thickness (IMT)', 'levothyroxine', and 'atherosclerosis'.
RESULTS: Twenty-six studies were eligible and included in the analysis. Overall, the studies encompassed a total of 36.434 patients included in this review. Most studies indicated a proportional correlation between IMT and thyroid dysfunction. Levothyroxine (L-T4) replacement led to significant decrease of IMT after 1 year in most studies.
CONCLUSION: Most studies have concluded that thyroid dysfunction is associated with arterial wall remodeling and, thus, with increased cardiovascular risk. However, the exact mechanistic background of pathological structural changes in the arterial wall is still unsettled. Large randomized controlled studies are required to definitively address the extent to which T4 replacement therapy might benefit patients with subclinical thyroid disorders.
Copyright© 2020, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.
Abstract/Text
CONTEXT: Hyperthyroidism is associated with low levels of cholesterol and triglycerides, and hypothyroidism is associated with hypercholesterolemia and hypertriglyceridemia.
OBJECTIVE: The aim of this systematic review was to investigate the impact of therapy for overt and subclinical hyper- and hypothyroidism on serum lipids.
DATA SOURCES: We searched MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials, the Cochrane Database of Systematic Reviews, and Scopus from 1970 through April 5, 2018.
STUDY SELECTION: Pairs of independent reviewers selected randomized and observational studies evaluating lipid parameters in patients undergoing treatment for hyper- or hypothyroidism.
DATA EXTRACTION: Pairs of independent reviewers extracted data and appraised studies.
DATA SYNTHESIS: Treatment of overt hyperthyroidism showed a significant increase in total cholesterol (TC) by 44.50 mg/dL (95% confidence interval [CI]: 37.99, 51.02), low-density lipoprotein cholesterol (LDL-C) by 31.13 mg/dL (95% CI: 24.33, 37.93), high-density lipoprotein cholesterol (HDL-C) by 5.52 mg/dL (95% CI: 1.48, 9.56), apolipoprotein A (Apo A) by 15.6 mg/dL (95% CI: 10.38, 20.81), apolipoprotein B (apo B) by 26.12 mg/dL (95% CI: 22.67, 29.57), and lipoprotein (Lp[a]) by 4.18 mg/dL (95% CI: 1.65, 6.71). There was no significant change in triglyceride (TG) levels. Treatment of subclinical hyperthyroidism did not change any lipid parameters significantly. Levothyroxine therapy in overt hypothyroidism showed a statistically significant decrease in TC by -58.4 mg/dL (95% CI: -64.70, -52.09), LDL-C by -41.11 mg/dL (95% CI: -46.53, -35.69), HDL-C by -4.14 mg/dL (95% CI: -5.67, -2.61), TGs by -7.25 mg/dL (95% CI: -36.63, 17.87), apo A by -12.59 mg/dL (95% CI: -17.98, -7.19), apo B by -33.96 mg/dL (95% CI: 41.14, -26.77), and Lp(a) by -5.6 mg/dL (95% CI: -9.06, -2.14). Levothyroxine therapy in subclinical hypothyroidism showed similar changes but with a smaller magnitude. The studies contained varied population characteristics, severity of thyroid dysfunction, and follow-up duration.
CONCLUSIONS: Treatment of overt but not subclinical hyperthyroidism is associated with worsening of the lipid profile. Levothyroxine therapy in both overt and subclinical hypothyroidism leads to improvement in the lipid profile, with a smaller magnitude of improvement in subclinical hypothyroidism.
© The Author(s) 2020. Published by Oxford University Press on behalf of the Endocrine Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Abstract/Text
CONTEXT: Benefits of thyroid hormone therapy on mortality in adults with subclinical hypothyroidism remain undetermined.
OBJECTIVE: To summarize the impact of thyroid hormone therapy on mortality in adults with subclinical hypothyroidism.
DATA SOURCES: PubMed, Embase, Scopus, Web of Science, and Clinicaltrials.gov from inception until April 25, 2020.
STUDY SELECTION: Studies comparing the effect of thyroid hormone therapy with that of placebo or no therapy in adults with subclinical hypothyroidism on all-cause and/or cardiovascular mortality.
DATA EXTRACTION: Two reviewers independently extracted data and performed quality assessments. Random-effects models for meta-analyses were used.
DATA SYNTHESIS: Five observational studies and 2 randomized controlled trials with 21 055 adults were included. Overall, thyroid hormone therapy was not significantly associated with all-cause (pooled relative risk [RR] = 0.95, 95% confidence interval [CI]: 0.75-1.22, P = .704) or cardiovascular (pooled RR = 0.99, 95% CI: 0.82-1.20, P = .946) mortality. Subgroup analyses revealed that in younger adults (aged <65-70 years), thyroid hormone therapy was significantly associated with a lower all-cause (pooled RR = 0.50, 95% CI: 0.29-0.85, P = .011) and cardiovascular (pooled RR = 0.54, 95% CI: 0.37-0.80, P = .002) mortality. However, no significant association between thyroid hormone therapy and mortality was observed in older adults (aged ≥65-70 years).
CONCLUSIONS: Use of thyroid hormone therapy does not provide protective effects on mortality in older adults with subclinical hypothyroidism. However, thyroid hormone therapy for subclinical hypothyroidism may show benefits on morality in adults aged <65 to 70 years.
© The Author(s) 2020. Published by Oxford University Press on behalf of the Endocrine Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Abstract/Text
BACKGROUND: Levothyroxine replacement therapy may decrease the risk of adverse pregnancy outcomes among women with subclinical hypothyroidism (SCH). The aim of this study is to conduct a systematic review and meta-analysis to examine the risk of adverse pregnancy, perinatal, and early childhood outcomes among women with SCH treated with levothyroxine.
METHODS: A systematic literature search was conducted using Ovid-Medline, Ovid-EMBASE, Pubmed (non-Medline), Ebsco-CINAHL Plus with full text and Cochrane Library databases. Randomized controlled studies (RCTs) and observational studies examining the association between treatment of SCH during pregnancy and our outcomes of interest were included. Studies that compared levothyroxine treatment versus no treatment were eligible for inclusion. Data from included studies were extracted and quality assessment was performed by two independent reviewers.
RESULTS: Seven RCTs and six observational studies met our inclusion criteria. A total of 7342 individuals were included in these studies. RCTs demonstrated several sources of bias, with lack of blinding of the participants or research personnel; only one study was fully blinded. In the observational studies, there was moderate to serious risk of bias due to lack of adjustment for certain confounding variables, participant selection, and selective reporting of results. Pooled analyses showed decreased risk of pregnancy loss (RR: 0.79; 95% CI: 0.67 to 0.93) and neonatal death (RR: 0.35; 95% CI: 0.17 to 0.72) associated with levothyroxine treatment during pregnancy among women with SCH. There were no associations between levothyroxine treatment and outcomes during labour and delivery, or cognitive status in children at 3 or 5 years of age.
CONCLUSION: Treatment of SCH with levothyroxine during pregnancy is associated with decreased risks of pregnancy loss and neonatal death. Given the paucity of available data and heterogeneity of included studies, additional studies are needed to address the benefits of levothyroxine use among pregnant women with SCH.
Abstract/Text
The second most prevalent endocrine condition affecting women of reproductive age is thyroid disease. The difference between an increased thyroid-stimulating hormone (TSH) concentration and a normal free thyroxine hormone level is used to identify subclinical hypothyroidism. Thyroid autoantibodies, independent of thyroid hormone levels, are used to diagnose autoimmune thyroid disease (ATD). Thyroxine can help infertile women with these two types of thyroid illnesses have better birth outcomes during fertility treatment. We performed a systematic review using PubMed (Medline) as a major database and some other sources EMBASE, the Cochrane Library, Web of Science, Scopus, and Science Direct. We concentrated on four studies, including 806 patients. Our goal is to investigate the efficacy and risks of levothyroxine therapy in infertile women who are receiving fertility treatments and have subclinical hypothyroidism or adequate thyroid function as well as thyroid autoimmunity (euthyroid autoimmune thyroid disorder). Thyroid activity in hypothyroid women should be tracked at pregnancy confirmation and closely monitored during the pregnancy. Early in pregnancy, the dosage of levothyroxine (LT4) can be raised. To ensure optimum TSH levels during breastfeeding, we recommend that patients who are followed in the primary sector have their LT4 dose increased by their general practitioner before their first referral to an endocrinological outpatient clinic. It's important to pay more attention to and track pregnant women with hypothyroidism, who consider pregnancy, to get the best results. LT4 therapy can help subfertile women with subclinical hypothyroidism who are having in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) since it improves embryo growth, implantation rate, and live birth rate.
Copyright © 2021, Myneni et al.
Abstract/Text
OBJECTIVE: To evaluate the effect of levothyroxine therapy on pregnancy outcomes compared with placebo or no treatment in women without overt hypothyroidism with presence of thyroid peroxidase antibodies (TPOAb) and/or thyroglobulin antibodies (TgAb).
DESIGN: Systematic review and meta-analysis of randomised controlled trials STUDY ELIGIBILITY CRITERIA: Prespecified criteria for inclusion were: randomised trials of levothyroxine versus control (placebo or no treatment) among women with positive TPOAb or TgAb who were pregnant or considering conception.
DATA SOURCES: Ovid MEDLINE, EMBASE, CINAHL, Cochrane Database of Systematic Reviews and Cochrane Central Register of Controlled Trials were searched from 1980 to 5 November 2020.
OUTCOME MEASURES: Prespecified data elements were extracted and where appropriate, meta-analyses were conducted. Main outcomes include pregnancy achieved, miscarriage, preterm delivery and live birth.
RISK OF BIAS ASSESSMENT: Cochrane Risk of Bias Tool for Quality Assessment of Randomised Controlled Trials.
RESULTS: From 3023 citations, 79 citations were identified for full-text review. Of these, six trials (total of 2263 women) were included for qualitative and quantitative analyses. Risk of bias was deemed low for only one trial. There was no significant difference in the relative risk (RR) of pregnancy achieved (RR 1.03; 95% CI 0.93 to 1.13), miscarriage (RR 0.93; 95% CI 0.76 to 1.14), preterm delivery (RR 0.66; 95% CI 0.39 to 1.10) or live births (RR 1.01; 95% CI 0.89 to 1.16) in thyroid autoimmune women treated with levothyroxine compared with controls. Sensitivity analyses of preterm birth identified study quality and timing of levothyroxine initiation as sources of heterogeneity.
CONCLUSIONS: Among pregnant women or women planning conception, with thyroid autoimmunity, there is a lack of evidence of benefit for levothyroxine use (moderate to high Grading of Recommendations, Assessment, Development and Evaluations). Recommendations to use levothyroxine in this setting need to be reconsidered.
PROSPERO REGISTRATION NUMBER: CRD42019130459.
© Author(s) (or their employer(s)) 2021. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.
Abstract/Text
Background: Combined therapy with levothyroxine (LT4)/L-triiodothyronine (LT3) has garnered attention among clinicians and patients as a potential treatment alternative to LT4 monotherapy. The objective of this study was to compare the benefits and harms of LT4/LT3 combined therapy and LT4 monotherapy for patients with hypothyroidism. Methods: A systematic search in MEDLINE, Scopus, EMBASE, Web of Science, and Cochrane Central Register of Controlled Trials was performed by a librarian from inception date until September 2020. Randomized clinical trials and quasiexperimental studies comparing combined therapy (LT4/LT3) versus monotherapy (LT4) for adult patients with hypothyroidism were considered for inclusion. Independent data extraction was performed by paired reviewers. A meta-analysis comparing standardized mean differences of the effect of each therapy was performed on clinical outcomes and patient preferences. Proportions of adverse events and reactions were assessed narratively. Results: A total of 1398 references were retrieved, from which 18 fulfilled the inclusion criteria. Results supported by evidence at low-to-moderate certainty evidence did not display a difference in treatment effect between therapies on clinical status, quality of life, psychological distress, depressive symptoms, and fatigue; all measured with standardized questionnaires. Furthermore, meta-analysis of patient preferences revealed higher proportions of choice for combined therapy (43%) when compared with monotherapy (23%) or having no preference (30%). When evaluating treatment adverse events or adverse reactions, similar proportions were observed between treatment groups; meta-analysis was not possible. Conclusions: The available evidence at low-to-moderate certainty demonstrates that there is no difference in clinical outcomes between LT4/LT3 combined therapy and LT4 monotherapy for treating hypothyroidism in adults, except for a higher proportion of patient preferring combined therapy. Adverse events and reactions appear to be similar across both groups, however, this observation is only narrative. These results could inform shared decision-making conversations between patients with hypothyroidism and their clinicians. PROSPERO Registration ID: CRD42020202658.
Avais Jabbar, Lorna Ingoe, Shahid Junejo, Peter Carey, Caroline Addison, Honey Thomas, Jehill D Parikh, David Austin, Kieren G Hollingsworth, Deborah D Stocken, Simon H S Pearce, John P Greenwood, Azfar Zaman, Salman Razvi
Effect of Levothyroxine on Left Ventricular Ejection Fraction in Patients With Subclinical Hypothyroidism and Acute Myocardial Infarction: A Randomized Clinical Trial.
JAMA. 2020 Jul 21;324(3):249-258. doi: 10.1001/jama.2020.9389.
Abstract/Text
Importance: Thyroid hormones play a key role in modulating myocardial contractility. Subclinical hypothyroidism in patients with acute myocardial infarction is associated with poor prognosis.
Objective: To evaluate the effect of levothyroxine treatment on left ventricular function in patients with acute myocardial infarction and subclinical hypothyroidism.
Design, Setting, and Participants: A double-blind, randomized clinical trial conducted in 6 hospitals in the United Kingdom. Patients with acute myocardial infarction including ST-segment elevation and non-ST-segment elevation were recruited between February 2015 and December 2016, with the last participant being followed up in December 2017.
Interventions: Levothyroxine treatment (n = 46) commencing at 25 µg titrated to aim for serum thyrotropin levels between 0.4 and 2.5 mU/L or identical placebo (n = 49), both provided in capsule form, once daily for 52 weeks.
Main Outcomes and Measures: The primary outcome measure was left ventricular ejection fraction at 52 weeks, assessed by magnetic resonance imaging, adjusted for age, sex, type of acute myocardial infarction, affected coronary artery territory, and baseline left ventricular ejection fraction. Secondary measures were left ventricular volumes, infarct size (assessed in a subgroup [n = 60]), adverse events, and patient-reported outcome measures of health status, health-related quality of life, and depression.
Results: Among the 95 participants randomized, the mean (SD) age was 63.5 (9.5) years, 72 (76.6%) were men, and 65 (69.1%) had ST-segment elevation myocardial infarction. The median serum thyrotropin level was 5.7 mU/L (interquartile range, 4.8-7.3 mU/L) and the mean (SD) free thyroxine level was 1.14 (0.16) ng/dL. The primary outcome measurements at 52 weeks were available in 85 patients (89.5%). The mean left ventricular ejection fraction at baseline and at 52 weeks was 51.3% and 53.8%, respectively, in the levothyroxine group compared with 54.0% and 56.1%, respectively, in the placebo group (adjusted difference in groups, 0.76% [95% CI, -0.93% to 2.46%]; P = .37). None of the 6 secondary outcomes showed a significant difference between the levothyroxine and placebo treatment groups. There were 15 (33.3%) and 18 (36.7%) cardiovascular adverse events in the levothyroxine and placebo groups, respectively.
Conclusions and Relevance: In this preliminary study involving patients with subclinical hypothyroidism and acute myocardial infarction, treatment with levothyroxine, compared with placebo, did not significantly improve left ventricular ejection fraction after 52 weeks. These findings do not support treatment of subclinical hypothyroidism in patients with acute myocardial infarction.
Trial Registration: isrctn.org Identifier: http://www.isrctn.com/ISRCTN52505169.
Lea Wildisen, Martin Feller, Cinzia Del Giovane, Elisavet Moutzouri, Robert S Du Puy, Simon P Mooijaart, Tinh-Hai Collet, Rosalinde K E Poortvliet, Patricia Kearney, Terence J Quinn, Stefan Klöppel, Douglas C Bauer, Robin P Peeters, Rudi Westendorp, Drahomir Aujesky, Jacobijn Gussekloo, Nicolas Rodondi
Effect of Levothyroxine Therapy on the Development of Depressive Symptoms in Older Adults With Subclinical Hypothyroidism: An Ancillary Study of a Randomized Clinical Trial.
JAMA Netw Open. 2021 Feb 1;4(2):e2036645. doi: 10.1001/jamanetworkopen.2020.36645. Epub 2021 Feb 1.
Abstract/Text
Importance: Previous trials on the effect of levothyroxine on depressive symptom scores in patients with subclinical hypothyroidism were limited by small sample sizes (N = 57 to 94) and potential biases.
Objective: To assess the effect of levothyroxine on the development of depressive symptoms in older adults with subclinical hypothyroidism in the largest trial on this subject and to update a previous meta-analysis including the results from this study.
Design, Setting, and Participants: This predefined ancillary study analyzed data from participants in the Thyroid Hormone Replacement for Untreated Older Adults with Subclinical Hypothyroidism (TRUST) trial, a double-blind, randomized, placebo-controlled, parallel-group clinical trial conducted from April 2013 to October 31, 2016. The TRUST trial included adults aged 65 years or older diagnosed with subclinical hypothyroidism, defined as the presence of persistently elevated thyroid-stimulating hormone (TSH) levels (4.6-19.9 mIU/L) with free thyroxine (T4) within the reference range. Participants were identified from clinical and general practitioner laboratory databases and recruited from the community in Switzerland, the Netherlands, Ireland, and the UK. This ancillary study included a subgroup of 472 participants from the Netherlands and Switzerland; after exclusions, a total of 427 participants (211 randomized to levothyroxine and 216 to placebo) were analyzed. This analysis was conducted from December 1, 2019, to September 1, 2020.
Interventions: Randomization to either levothyroxine or placebo.
Main Outcomes and Measures: Depressive symptom scores after 12 months measured with the Geriatric Depression Scale (GDS-15), with higher scores indicating more depressive symptoms (minimal clinically important difference = 2).
Results: A total of 427 participants with subclinical hypothyroidism (mean [SD] age, 74.52 [6.29] years; 239 women [56%]) were included in this analysis. The mean (SD) TSH level was 6.57 (2.22) mIU/L at baseline and decreased after 12 months to 3.83 (2.29) mIU/L in the levothyroxine group; in the placebo group, it decreased from 6.55 (2.04) mIU/L to 5.91 (2.66) mIU/L. At baseline, the mean (SD) GDS-15 score was 1.26 (1.85) in the levothyroxine group and 0.96 (1.58) in the placebo group. The mean (SD) GDS-15 score at 12 months was 1.39 (2.13) in the levothyroxine and 1.07 (1.67) in the placebo group with an adjusted between-group difference of 0.15 for levothyroxine vs placebo (95% CI, -0.15 to 0.46; P = .33). In a subgroup analysis including participants with a GDS-15 of at least 2, the adjusted between-group difference was 0.61 (95% CI, -0.32 to 1.53; P = .20). Results did not differ according to age, sex, or TSH levels. A previous meta-analysis (N = 278) on the association of levothyroxine with depressive symptoms was updated to include these findings, resulting in an overall standardized mean difference of 0.09 (95% CI, -0.05 to 0.22).
Conclusions and Relevance: This ancillary study of a randomized clinical trial found that depressive symptoms did not differ after levothyroxine therapy compared with placebo after 12 months; thus, these results do not provide evidence in favor of levothyroxine therapy in older persons with subclinical hypothyroidism to reduce the risk of developing depressive symptoms.
Trial Registration: ClinicalTrials.gov Identifier: NCT01853579.
Mirah J Stuber, Elisavet Moutzouri, Martin Feller, Cinzia Del Giovane, Douglas C Bauer, Manuel R Blum, Tinh-Hai Collet, Jacobijn Gussekloo, Simon P Mooijaart, Vera J C McCarthy, Drahomir Aujesky, Rudi Westendorp, David J Stott, Nancy W Glynn, Patricia M Kearney, Nicolas Rodondi
Effect of Thyroid Hormone Therapy on Fatigability in Older Adults With Subclinical Hypothyroidism: A Nested Study Within a Randomized Placebo-Controlled Trial.
J Gerontol A Biol Sci Med Sci. 2020 Sep 16;75(9):e89-e94. doi: 10.1093/gerona/glaa123.
Abstract/Text
BACKGROUND: Fatigue often triggers screening for and treatment of subclinical hypothyroidism. However, data on the impact of levothyroxine on fatigue is limited and previous studies might not have captured all aspects of fatigue.
METHOD: This study is nested within the randomized, placebo-controlled, multicenter TRUST trial, including community-dwelling participants aged ≥65 and older, with persistent subclinical hypothyroidism (TSH 4.60-19.99 mIU/L, normal free thyroxine levels) from Switzerland and Ireland. Interventions consisted of daily levothyroxine starting with 50 μg (25 μg if weight <50 kg or known coronary heart diseases) together with dose adjustments to achieve a normal TSH and mock titration in the placebo group. Main outcome was the change in physical and mental fatigability using the Pittsburgh Fatigability Scale over 1 year, assessed through multivariable linear regression with adjustment for country, sex, and levothyroxine starting dose.
RESULTS: Among 230 participants, the mean ± standard deviation (SD) TSH was 6.2 ± 1.9 mIU/L at baseline and decreased to 3.1 ± 1.3 with LT4 (n = 119) versus 5.3 ± 2.3 with placebo (n = 111, p < .001) after 1 year. After adjustment we found no between-group difference at 1 year on perceived physical (0.2; 95% CI -1.8 to 2.1; p = .88), or mental fatigability (-1.0; 95% CI -2.8 to 0.8; p = .26). In participants with higher fatigability at baseline (≥15 points for the physical score [n = 88] or ≥13 points for the mental score [n = 41]), the adjusted between-group differences at 1 year were 0.4 (95% CI -3.6 to 2.8, p = .79) and -2.2 (95% CI -8.8 to 4.5, p = .51).
CONCLUSIONS: Levothyroxine in older adults with mild subclinical hypothyroidism provides no change in physical or mental fatigability.
© The Author(s) 2020. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Maria de Montmollin, Martin Feller, Shanthi Beglinger, Alex McConnachie, Drahomir Aujesky, Tinh-Hai Collet, Ian Ford, Jacobijn Gussekloo, Patricia M Kearney, Vera J C McCarthy, Simon Mooijaart, Rosalinde K E Poortvliet, Terence Quinn, David J Stott, Torquil Watt, Rudi Westendorp, Nicolas Rodondi, Douglas C Bauer
L-Thyroxine Therapy for Older Adults With Subclinical Hypothyroidism and Hypothyroid Symptoms: Secondary Analysis of a Randomized Trial.
Ann Intern Med. 2020 Jun 2;172(11):709-716. doi: 10.7326/M19-3193. Epub 2020 May 5.
Abstract/Text
BACKGROUND: L-thyroxine does not improve hypothyroid symptoms among adults with subclinical hypothyroidism (SCH). However, those with greater symptom burden before treatment may still benefit.
OBJECTIVE: To determine whether L-thyroxine improves hypothyroid symptoms and tiredness among older adults with SCH and greater symptom burden.
DESIGN: Secondary analysis of the randomized, placebo-controlled trial TRUST (Thyroid Hormone Replacement for Untreated Older Adults with Subclinical Hypothyroidism Trial). (ClinicalTrials.gov: NCT01660126).
SETTING: Switzerland, Ireland, the Netherlands, and Scotland.
PARTICIPANTS: 638 persons aged 65 years or older with persistent SCH (thyroid-stimulating hormone level of 4.60 to 19.9 mIU/L for >3 months and normal free thyroxine level) and complete outcome data.
INTERVENTION: L-thyroxine or matching placebo with mock dose titration.
MEASUREMENTS: 1-year change in Hypothyroid Symptoms and Tiredness scores (range, 0 to 100; higher scores indicate more symptoms) on the Thyroid-Related Quality-of-Life Patient-Reported Outcome Questionnaire among participants with high symptom burden (baseline Hypothyroid Symptoms score >30 or Tiredness score >40) versus lower symptom burden.
RESULTS: 132 participants had Hypothyroid Symptoms scores greater than 30, and 133 had Tiredness scores greater than 40. Among the group with high symptom burden, the Hypothyroid Symptoms score improved similarly between those receiving L-thyroxine (mean within-group change, -12.3 [95% CI, -16.6 to -8.0]) and those receiving placebo (mean within-group change, -10.4 [CI, -15.3 to -5.4]) at 1 year; the adjusted between-group difference was -2.0 (CI, -5.5 to 1.5; P = 0.27). Improvements in Tiredness scores were also similar between those receiving L-thyroxine (mean within-group change, -8.9 [CI, -14.5 to -3.3]) and those receiving placebo (mean within-group change, -10.9 [CI, -16.0 to -5.8]); the adjusted between-group difference was 0.0 (CI, -4.1 to 4.0; P = 0.99). There was no evidence that baseline Hypothyroid Symptoms score or Tiredness score modified the effects of L-thyroxine versus placebo (P for interaction = 0.20 and 0.82, respectively).
LIMITATION: Post hoc analysis, small sample size, and examination of only patients with 1-year outcome data.
CONCLUSION: In older adults with SCH and high symptom burden at baseline, L-thyroxine did not improve hypothyroid symptoms or tiredness compared with placebo.
PRIMARY FUNDING SOURCE: European Union FP7.
Baris Gencer, Elisavet Moutzouri, Manuel R Blum, Martin Feller, Tinh-Hai Collet, Cinzia Delgiovane, Bruno R da Costa, Eric Buffle, Pierre Monney, Vincent Gabus, Hajo Müller, Gerasimos P Sykiotis, Patricia Kearney, Jacobijn Gussekloo, Rudi Westendorp, David J Stott, Douglas C Bauer, Nicolas Rodondi
The Impact of Levothyroxine on Cardiac Function in Older Adults With Mild Subclinical Hypothyroidism: A Randomized Clinical Trial.
Am J Med. 2020 Jul;133(7):848-856.e5. doi: 10.1016/j.amjmed.2020.01.018. Epub 2020 Mar 12.
Abstract/Text
BACKGROUND: Subclinical hypothyroidism has been associated with heart failure, but only small trials assessed whether treatment with levothyroxine has an impact on cardiac function.
METHODS: In a randomized, double-blind, placebo-controlled, trial nested within the TRUST trial, Swiss participants ages ≥65 years with subclinical hypothyroidism (thyroid-stimulating hormone [TSH] 4.60-19.99 mIU/L; free thyroxine level within reference range) were randomized to levothyroxine (starting dose of 50 µg daily) to achieve TSH normalization or placebo. The primary outcomes were the left ventricular ejection fraction for systolic function and the ratio between mitral peak velocity of early filling to early diastolic mitral annular velocity (E/e' ratio) for diastolic function. Secondary outcomes included e' lateral/septal, left atrial volume index, and systolic pulmonary artery pressure.
RESULTS: A total of 185 participants (mean age 74.1 years, 47% women) underwent echocardiography at the end of the trial. After a median treatment duration of 18.4 months, the mean TSH decreased from 6.35 mIU/L to 3.55 mIU/L with levothyroxine (n = 96), and it remained elevated at 5.29 mIU/L with placebo (n = 89). The adjusted between-group difference was not significant for the mean left ventricular ejection fraction (62.7% vs 62.5%, difference = 0.4%, 95% confidence interval -1.8% to 2.5%, P = 0.72) and the E/e' ratio (10.6 vs 10.1, difference 0.4, 95% confidence interval -0.7 to 1.4, P = 0.47). No differences were found for the secondary diastolic function parameters or for interaction according to sex, baseline TSH, preexisting heart failure, and treatment duration (P value >0.05).
CONCLUSION: Systolic and diastolic heart function did not differ after treatment with levothyroxine compared with placebo in older adults with mild subclinical hypothyroidism.
Copyright © 2020 Elsevier Inc. All rights reserved.
Elena Gonzalez Rodriguez, Mirah Stuber, Cinzia Del Giovane, Martin Feller, Tinh-Hai Collet, Axel L Löwe, Manuel R Blum, Nicolien A van Vliet, Diana van Heemst, Patricia M Kearney, Jacobijn Gussekloo, Simon Mooijaart, Rudi G J Westendorp, David J Stott, Daniel Aeberli, Douglas C Bauer, Didier Hans, Nicolas Rodondi
Skeletal Effects of Levothyroxine for Subclinical Hypothyroidism in Older Adults: A TRUST Randomized Trial Nested Study.
J Clin Endocrinol Metab. 2020 Jan 1;105(1). doi: 10.1210/clinem/dgz058.
Abstract/Text
CONTEXT: Both thyroid dysfunction and levothyroxine (LT4) therapy have been associated with bone loss, but studies on the effect of LT4 for subclinical hypothyroidism (SHypo) on bone yielded conflicting results.
OBJECTIVE: To assess the effect of LT4 treatment on bone mineral density (BMD), Trabecular Bone Score (TBS), and bone turnover markers (BTMs) in older adults with SHypo.
DESIGN AND INTERVENTION: Planned nested substudy of the double-blind placebo-controlled TRUST trial. Participants with SHypo were randomized to LT4 with dose titration versus placebo with computerized mock titration.
SETTING AND PARTICIPANTS: 196 community-dwelling adults over 65 years enrolled at the Swiss TRUST sites had baseline and 1-year follow-up bone examinations; 4 participants withdrew due to adverse events not related to treatment.
MAIN OUTCOME MEASURES: One-year percentage changes of BMD, TBS, and 2 serum BTMs (serum CTX-1 [sCTX] and procollagen type 1 N-terminal polypeptide [P1NP]). Student's t-test for unadjusted analyses and linear regression adjusted for clinical center and sex were performed.
RESULTS: Mean age was 74.3 years ± 5.7, 45.4% were women, and 19.6% were osteoporotic. The unadjusted 1-year change in lumbar spine BMD was similar between LT4 (+0.8%) and placebo-treated groups (-0.6%; between-groups difference +1.4%: 95% confidence interval [CI] -0.1 to 2.9, P = .059). Likewise, there were no between-group differences in 1-year change in TBS (-1.3%: 95% CI -3.1 to 0.6, P = .19), total hip BMD (-0.2%: 95% CI -1.1 to 0.1, P = .61), or BTMs levels (sCTX +24.1%: 95% CI -7.9 to 56.2, P = .14), or after adjustment for clinical centers and sex.
CONCLUSIONS: Over 1-year levothyroxine had no effect on bone health in older adults with SHypo.
REGISTRATION: ClinicalTrial.gov NCT01660126 and NCT02491008.
© Endocrine Society 2020. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Maged M Costantine, Karen Smith, Elizabeth A Thom, Brian M Casey, Alan M Peaceman, Michael W Varner, Yoram Sorokin, Uma M Reddy, Ronald J Wapner, Kim Boggess, Alan T N Tita, Dwight J Rouse, Baha Sibai, Jay D Iams, Brian M Mercer, Jorge E Tolosa, Steve N Caritis, J Peter VanDorsten, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) Maternal-Fetal Medicine Units (MFMU) Network, Bethesda, MD
Effect of Thyroxine Therapy on Depressive Symptoms Among Women With Subclinical Hypothyroidism.
Obstet Gynecol. 2020 Apr;135(4):812-820. doi: 10.1097/AOG.0000000000003724.
Abstract/Text
OBJECTIVE: To estimate the effect of antenatal treatment of subclinical hypothyroidism on maternal depressive symptoms.
METHODS: We conducted an ancillary study to a multicenter trial in women with singleton pregnancies diagnosed with subclinical hypothyroidism randomized to antenatal thyroxine therapy or placebo. Treatment was discontinued at the end of pregnancy. Women with overt thyroid disease, diabetes, autoimmune disease, and those diagnosed with depression were excluded. Participants were assessed for depressive symptoms using the Center for Epidemiological Studies-Depression scale (CES-D) before starting the study drug (between 11 and 20 weeks of gestation), between 32 and 38 weeks of gestation, and at 1 year postpartum. The primary outcome was maternal depressive symptoms score as assessed using the CES-D. Secondary outcome was the percentage of women who scored 16 or higher on the CES-D, as such a score is considered screen-positive for depression.
RESULTS: Two hundred forty-five (36.2% of parent trial) women with subclinical hypothyroidism were allocated to thyroxine (n=124) or placebo (n=121). Median CES-D scores and the proportion of participants with positive scores were similar at baseline between the two groups. Treatment with thyroxine was not associated with differences in CES-D scores (10 [5-15] vs 10 [5-17]; P=.46) or in odds of screening positive in the third trimester compared with placebo, even after adjusting for baseline scores (24.3% vs 30.1%, adjusted odds ratio 0.63, 95% CI 0.31-1.28, P=.20). At 1 year postpartum, CES-D scores were not different (6 [3-11] vs 6 [3-12]; P=.79), nor was the frequency of screen-positive CES-D scores in the treated compared with the placebo group (9.7% vs 15.8%; P=.19). Treatment with thyroxine during pregnancy was also not associated with differences in odds of screening positive at the postpartum visit compared with placebo even after adjusting for baseline scores. Sensitivity analysis including women who were diagnosed with depression by the postpartum visit did not change the results.
CONCLUSIONS: This study did not achieve its planned sample size, thus our conclusions may be limited, but in this cohort of pregnant women with subclinical hypothyroidism, antenatal thyroxine replacement did not improve maternal depressive symptoms.
Abstract/Text
Levothyroxine (l-thyroxine, l-T4) is a drug of choice for treating congenital and primary hypothyroidism. Although clinically significant interactions between l-T4 and food can alter the safety and efficacy of the treatment, they still seem to be generally underestimated by patients, physicians and pharmacists. This review aimed to investigate the effects of meals, beverages, and dietary supplements consumption on l-T4 pharmacokinetics and pharmacodynamics, to identify the most evident interactions, and to perform the recommendations for safe co-administering of l-T4 and food. A total of 121 studies were identified following a systematic literature search adhering to PRISMA guidelines. After full-text evaluation, 63 studies were included. The results proved that l-T4 ingestion in the morning and at bedtime are equally effective, and also that the co-administration of l-T4 with food depends on the drug formulation. We found limited evidence for l-T4 interactions with coffee, soy products, fiber, calcium or iron supplements, and enteral nutrition but interestingly they all resulted in decreased l-T4 absorption. The altered l-T4 efficacy when ingested with milk, juices, papaya, aluminium-containing preparations, and chromium supplements, as well as observed enhancement effect of vitamin C on l-T4 absorption, shall be further investigated in larger, well-designed studies. Novel formulations are likely to solve the problem of coffee, calcium and iron induced malabsorption of l-T4. Maintaining a proper time interval between l-T4 and food intake, especially for coffee and calcium, or iron supplements, provides another effective method of eliminating such interactions.
Abstract/Text
Background: The American Thyroid Association Guidelines on Thyroid Disease During Pregnancy and the Postpartum (ATA Guidelines) were published in 2017, with an update not expected for another 5 years. Since release of the 2017 ATA Guidelines, greater than 500 articles have been published in the field. Furthermore, there are presently 14 prospective, interventional trials in progress registered at Clinicaltrials.gov Static guidelines updated every 5-7 years fail to provide timely evidence-based guidance to practicing clinicians. Consequently, guideline development should move toward the creation of dynamic documents. The present article reviews the literature published since the 2017 ATA Guidelines, both to benefit clinicians in practice and to make the case for Dynamic ATA Guidelines. Methods: Using the search terms "thyroid" and "pregnancy," a systematic review of literature published in Pubmed from 3/1/2017 to 12/31/2018 was conducted. The titles and/or abstracts of all articles were reviewed. All articles were classified by subject headings used in the 2017 ATA Guidelines. English-text articles classified under "hypothyroidism" or "thyroid autoimmunity" were examined in full-text. Using the questions and recommendations put forth by the previous ATA Guidelines, relevant articles were selected for discussion in this review. Results: At the time of the search, 659 unique articles on "thyroid and pregnancy" were identified, including 66 original studies on hypothyroidism and 26 on thyroid autoimmunity. Of these, 26 studies on hypothyroidism and 18 studies on thyroid autoimmunity were selected for inclusion in this review based on specific questions in the 2017 ATA Guidelines. Based on these 44 articles, we propose two specific changes to the 2017 ATA Guidelines. Conclusion: Based on new research, we recommend the 2017 ATA Guidelines be updated to recommend against treating thyroid antibody-negative women diagnosed with subclinical hypothyroidism in the second trimester or later; to reflect new, moderate-quality evidence supporting the treatment of thyroid peroxidase antibody-negative women with elevated thyroid stimulating hormone levels in the first trimester or earlier; and to recommend against treatment of euthyroid, thyroid peroxidase antibody-positive women undergoing assisted reproductive technology. Transitioning to a Dynamic ATA Guidelines would allow for these and future recommendations to be implemented in real time.
Copyright © 2020 Dong, Stephenson and Stagnaro-Green.
Abstract/Text
OBJECTIVE: To determine whether overt/subclinical hypothyroidism and/or thyroid autoimmunity is associated with recurrent pregnancy loss (RPL) and whether treatment improves outcomes.
DESIGN: Systematic review and meta-analysis.
SETTING: University obstetrics and gynecology departments.
PATIENT(S): Women with RPL and overt/subclinical hypothyroidism, and/or thyroid autoimmunity.
INTERVENTION(S): None.
MAIN OUTCOME MEASURE(S): Associations between RPL and overt/subclinical hypothyroidism and/or thyroid autoimmunity and any effects of treatment.
RESULT(S): After our review of articles from PubMed, EMBASE, Web of Science, and CENTRAL, we found two interventional studies in which levothyroxine did not improve the subsequent live-birth rate in women with subclinical hypothyroidism with or without thyroid antibodies. A meta-analysis of five studies revealed the prevalence of subclinical hypothyroidism in RPL to be 12.9% (95% confidence interval [CI], 0%-35.2%). A meta-analysis of 17 studies revealed a statistically significant association between RPL and thyroid autoimmunity (odds ratio 1.94; 95% CI, 1.43-2.64). However, a randomized study suggested that levothyroxine does not benefit euthyroid women with thyroid autoimmunity.
CONCLUSION(S): Based on the limited observational studies available, no association exists between RPL and subclinical hypothyroidism, nor does levothyroxine improve subsequent pregnancy outcomes. An association exists between RPL and thyroid autoimmunity, but levothyroxine does not improve subsequent pregnancy outcomes. Women with RPL should be screened/treated for overt thyroid disease but not thyroid autoimmunity. Thyroid antibody screening is not supported by the published studies, and further randomized studies are needed. No recommendation regarding the treatment of subclinical hypothyroidism can be made at this time; prospective and randomized studies are urgently needed.
Copyright © 2019 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.
Abstract/Text
BACKGROUND: The impact of subclinical hypothyroidism (SCH) and of levothyroxine replacement in pregnant women with SCH is unclear. The aims of this study were to assess (i) the impact of SCH during pregnancy on maternal and neonatal outcomes, and (ii) the effect of levothyroxine replacement therapy in these patients.
METHODS: Ovid MEDLINE In-Process & Other Non-Indexed Citations, Ovid MEDLINE, the Cochrane Controlled Trials Register, Ovid EMBASE, Web of Science, and Scopus were searched from inception to January 2015. Randomized trials and cohort studies of pregnant women with SCH that examined adverse pregnancy and neonatal outcomes were included. Reviewers extracted data and assessed methodological quality in duplicate. Eighteen cohort studies at low-to-moderate risk of bias were included. Compared with euthyroid pregnant women, pregnant women with SCH were at higher risk for pregnancy loss (relative risk [RR] 2.01 [confidence interval (CI) 1.66-2.44]), placental abruption (RR 2.14 [CI 1.23-3.70]), premature rupture of membranes (RR 1.43 [CI 1.04-1.95]), and neonatal death (RR 2.58 [CI 1.41-4.73]). One study at high risk of bias compared pregnant women with SCH who received levothyroxine to those who did not and found no significant decrease in the rate of pregnancy loss, preterm delivery, gestational hypertension, low birth weight, or low Apgar score.
CONCLUSIONS: SCH during pregnancy is associated with multiple adverse maternal and neonatal outcomes. The value of levothyroxine therapy in preventing these adverse outcomes remains uncertain.
Abstract/Text
Infertile women sometimes associated with subclinical hypothyroidism (SCH). The guidelines of the American Endocrine Society, and American Association of Clinical Endocrinologists and American Thyroid Association recommend treatment with thyroxine (T4) for patients with SCH who want to have children. We examined 69 female infertile patients with SCH and the effects of levothyroxine (l-T4) therapy on pregnancy rates and pregnancy outcomes were observed. Fifty-eight (84.1%) patients successfully conceived during the T4 treatment period (Group A), although 17 patients (29.3%) had miscarriage afterward. The remaining 11 patients continued to be infertile (Group B). The median TSH value in Group A before the T4 treatment was 5.46 μIU/mL (range 3.1-13.3) and this significantly decreased to 1.25 μIU/mL (range 0.02-3.75) during the treatment (p<0.001). The estimated duration of infertility before the T4 treatment was 2.8±1.7 years and the duration until pregnancy after the treatment was significantly shorter at 0.9±0.9 years (p<0.001). Shortening of the infertile period after the T4 therapy was observed not only in patients who were treated with assisted reproductive technology (ART) but also in patients who conceived spontaneously in Group A. Administered T4 dose was 54.3±14.2 μg before pregnancy and 68.5±22.8 μg during pregnancy (p<0.001). Anti-thyroid autoantibodies were identified in 42.0% of all patients and no significant difference was observed in positivity between Group A and Group B. High successful pregnancy rate and shorter duration of infertility until pregnancy after T4 treatment strongly suggest that T4 enhanced fertility in infertile patients with SCH.
Abstract/Text
BACKGROUND: Thyroid disease is the second most common endocrine disorder affecting women of reproductive age. Subclinical hypothyroidism is diagnosed by an elevated thyroid-stimulating hormone concentration with a normal concentration of free thyroxine hormone. Autoimmune thyroid disease (ATD) is diagnosed by the presence of thyroid autoantibodies, regardless of thyroid hormone levels. Thyroxine may be a useful treatment for subfertile women with these two specific types of thyroid disease for improving pregnancy outcomes during assisted reproduction.
OBJECTIVES: To evaluate the efficacy and harms of levothyroxine replacement in subfertile women with subclinical hypothyroidism or with normal thyroid function and thyroid autoimmunity (euthyroid autoimmune thyroid disease, or euthyroid ATD) undergoing assisted reproduction.
SEARCH METHODS: We searched the Cochrane Gynaecology and Fertility (CGF) Group specialised register, CENTRAL, MEDLINE, Embase, PsycINFO, CINAHL and two trials registers together with reference checking and contact with study authors and experts in the field to identify studies. We searched for all published and unpublished randomised controlled trials (RCTs) comparing thyroxine with no treatment or placebo, without language restrictions, from inception to 8 April 2019, and in consultation with the Cochrane CGF Information Specialist.
SELECTION CRITERIA: We included women undergoing assisted reproduction treatment, meaning both in vitro fertilisation and intracytoplasmic sperm injection, with a history of subfertility and with subclinical hypothyroidism or with euthyroid ATD. We excluded women with a previously known clinical hypothyroidism or already taking thyroxine or tri-iodothyronine. RCTs compared thyroxine (levothyroxine) with either placebo or no treatment.
DATA COLLECTION AND ANALYSIS: We used standard methodological procedures expected by Cochrane. Our primary review outcomes were live birth and adverse events of thyroxine; our secondary outcomes were clinical pregnancy, multiple pregnancy and miscarriage.
MAIN RESULTS: The review included four studies with 820 women. The included studies were of overall low risk of bias. Using GRADE methodology, we assessed the quality of evidence for the primary outcomes of this review to be very low- to low-quality evidence. Evidence was downgraded for imprecision as it was based on single, small trials with wide confidence intervals (CI). We were able to include data from three of the four included studies.In one study of women with both subclinical hypothyroidism and positive or negative anti-TPO antibodies (autoimmune disease), the evidence suggested that thyroxine replacement may have improved live birth rate (RR 2.13, 95% CI 1.07 to 4.21; 1 RCT, n = 64; low-quality evidence) and it may have led to similar miscarriage rates (RR 0.11, 95% CI 0.01 to 1.98; 1 RCT, n = 64; low-quality evidence). The evidence suggested that women with both subclinical hypothyroidism and positive or negative anti-TPO antibodies would have a 25% chance of a live birth with placebo or no treatment, and that the chance of a live birth in these women using thyroxine would be between 27% and 100%.In women with normal thyroid function and thyroid autoimmunity (euthyroid ATD), treatment with thyroxine replacement compared with placebo or no treatment may have led to similar live birth rates (risk ratio (RR) 1.04, 95% CI 0.83 to 1.29; 2 RCTs, number of participants (n) = 686; I2 = 46%; low-quality evidence) and miscarriage rates (RR 0.83, 95% CI 0.47 to 1.46, 2 RCTs, n = 686, I2 = 0%; low-quality evidence). The evidence suggested that women with normal thyroid function and thyroid autoimmunity would have a 31% chance of a live birth with placebo or no treatment, and that the chance of a live birth in these women using thyroxine would be between 26% and 40%.Adverse events were rarely reported. One RCT reported 0/32 in the thyroxine replacement group and 1/32 preterm births in the control group in women diagnosed with subclinical hypothyroidism and positive or negative anti-TPO antibodies. One RCT reported 21/300 preterm births in the thyroxine replacement group and 19/300 preterm births in the control group in women diagnosed with positive anti-TPO antibodies. None of the RCTs reported on other maternal pregnancy complications, foetal complications or adverse effects of thyroxine.
AUTHORS' CONCLUSIONS: We could draw no clear conclusions in this systematic review due to the very low to low quality of the evidence reported.
Abstract/Text
OBJECTIVE: Achieving optimal thyroid hormone replacement is more difficult in TSH deficiency compared to primary hypothyroidism because of the inability to be guided by serum TSH levels. A combination of clinical symptoms and free thyroxine levels (fT4) are typically used to make a diagnosis and monitor replacement. We investigated the diagnosis of TSH deficiency in patients with pituitary disease and the adequacy of levothyroxine replacement compared with primary thyroid disease.
DESIGN: Using our department's clinical information system, we identified all patients with a diagnosis of any type of pituitary tumour who had been seen in clinic over a 2-year period. We divided the patients into those at high risk and low risk of TSH deficiency based on the presence of macroadenoma and/or intervention by surgery or radiotherapy. We compared fT4 values in these patients with values in patients with primary thyroid disease in our thyrotoxicosis shared-care scheme (TSC) and hypothyroid register within the same timescale, assessing only those samples considered euthyroid in which TSH was in the normal range.
RESULTS: A database query identified 525 patients with a pituitary tumour of whom 344 were considered at high risk of TSH deficiency. A free T4 (fT4) value was found for 514 patients (97·9%). TSC and thyroid register databases revealed fT4 values for comparison with simultaneous normal TSH in patients on no treatment (n = 3777 samples) or on levothyroxine alone (n = 11,805). fT4 levels overall were lower in pituitary patients than in equivalent controls. Of the high risk group not taking levothyroxine 17% had a free T4 ≤ 11 pmol/l compared to only 8·4% of untreated controls. Furthermore, 38·9% of patients on levothyroxine had a free T4 ≤ 13 pmol/l compared to 9·5% of controls on levothyroxine with previous thyrotoxicosis and 13·4% of controls with primary hypothyroidism. Median fT4 in controls on levothyroxine was 16 pmol/l and 20-80th centile range was 14-19 pmol/l.
CONCLUSION: Levothyroxine doses were generally under-replaced in pituitary patients compared to primary thyroid disease and the data imply that some untreated patients were actually TSH deficient. The distribution of fT4 in patients with primary thyroid disease on levothyroxine may guide optimum replacement levels in pituitary disease.
© 2011 Blackwell Publishing Ltd.
