Abstract/Text: BACKGROUND: The effectiveness of dementia screening depends on the availability of suitable screening tools with good sensitivity and specificity to confidently distinguish normal age-related cognitive decline from dementia. The aim of this study was to evaluate the discriminant validity of 7 screening measures for dementia.
METHODS: A sample of 140 participants aged ≥60 years living in a residential facility for the aged were assessed clinically and assigned caseness for dementia using the Diagnostic and Statistical Manual of Mental Disorders, 4th edition, text revised diagnostic criteria. Sensitivity and specificity of a selection of the following screening measures were tested using receiver operating characteristic (ROC) analysis for individual and combined tests: the Mini-Mental State Examination (MMSE), Six-Item Screener (SIS), Subjective Memory Complaint, Subjective Memory Complaint Clinical (SMCC), Subjective Memory Rating Scale (SMRS), Deterioration Cognitive Observee (DECO) and the Clock Drawing Test (CDT).
RESULTS: Using ROC analyses, the SMCC, MMSE and CDT were found to be 'moderately accurate' in screening for dementia with an area under the curve (AUC) >0.70. The AUCs for the SIS (0.526), SMRS (0.661) and DECO (0.687) classified these measures as being 'less accurate'. At recommended cutoff scores, the SMCC had a sensitivity of 90.9% and specificity of 45.7%; the MMSE had a sensitivity of 63.6% and a specificity of 76.0%, and the CDT had a sensitivity of 44.4% and a specificity of 88.9%. Combining the SMCC and MMSE did not improve their predictive power except for a modest increase when using the sequential rule.
CONCLUSION: The SMCC is composed of valid screening questions that have high sensitivity, are simple to administer and ideal for administration at the community or primary health care level as a first level of 'rule-out' screening. The MMSE can be included at a second stage of screening at the general hospital level and the CDT in specialist clinical settings. Sequential use of the SMCC and MMSE will improve the specificity of the former and the sensitivity of the latter.

Copyright © 2013 S. Karger AG, Basel.

Abstract/Text: BACKGROUND: Cholinesterase inhibitors (ChEIs) represent the mainstay of symptomatic treatment in Alzheimer's disease. Three medications belonging to this class are presently widely available. These agents differ in their individual mechanisms of action and pharmacokinetic properties. Switching ChEIs can be a reasonable option in cases of intolerance or lack of clinical benefit.
METHODS: A systematic literature search of switching ChEIs was conducted, and all studies specifically evaluating this issue were identified. Published consensus guidelines were also searched for recommendations on ChEI switching.
RESULTS: Eight clinical studies are summarized and discussed. All of these studies are open-label or retrospective and they cannot be readily compared because of heterogeneity in design, number of patients, agents used, and endpoints. Switching in most of these studies was done for both "lack of benefit" or "loss of response" after up to 29 months of treatment. Nevertheless, the majority of studies did not include individuals switched for lack of response after several years of treatment. Lack of satisfactory response or intolerance with the initial agent was not predictive of similar results with the second agent.
CONCLUSIONS: In light of these findings, we propose the following practical approach to switching ChEIs: (1) in the case of intolerance, switching to a second agent should be done only after the complete resolution of side-effects following discontinuation of the initial agent; (2) in the case of lack of efficacy, switching can be done overnight, with a quicker titration scheme thereafter; (3) switching ChEIs is not recommended in individuals who show loss of benefit several years after initiation of treatment.