Abstract/Text: The revised criteria for the classification of rheumatoid arthritis (RA) were formulated from a computerized analysis of 262 contemporary, consecutively studied patients with RA and 262 control subjects with rheumatic diseases other than RA (non-RA). The new criteria are as follows: 1) morning stiffness in and around joints lasting at least 1 hour before maximal improvement; 2) soft tissue swelling (arthritis) of 3 or more joint areas observed by a physician; 3) swelling (arthritis) of the proximal interphalangeal, metacarpophalangeal, or wrist joints; 4) symmetric swelling (arthritis); 5) rheumatoid nodules; 6) the presence of rheumatoid factor; and 7) radiographic erosions and/or periarticular osteopenia in hand and/or wrist joints. Criteria 1 through 4 must have been present for at least 6 weeks. Rheumatoid arthritis is defined by the presence of 4 or more criteria, and no further qualifications (classic, definite, or probable) or list of exclusions are required. In addition, a "classification tree" schema is presented which performs equally as well as the traditional (4 of 7) format. The new criteria demonstrated 91-94% sensitivity and 89% specificity for RA when compared with non-RA rheumatic disease control subjects.

Abstract/Text: OBJECTIVE: Trials of rheumatoid arthritis (RA) treatments report the average response in multiple outcome measures for treated patients. It is more clinically relevant to test whether individual patients improve with treatment, and this identifies a single primary efficacy measure. Multiple definitions of improvement are currently in use in different trials. The goal of this study was to promulgate a single definition for use in RA trials.
METHODS: Using the American College of Rheumatology (ACR) core set of outcome measures for RA trials, we tested 40 different definitions of improvement, using a 3-step process. First, we performed a survey of rheumatologists, using actual patient cases from trials, to evaluate which definitions corresponded best to rheumatologists' impressions of improvement, eliminating most candidate definitions of improvement. Second, we tested 20 remaining definitions to determine which maximally discriminated effective treatment from placebo treatment and also minimized placebo response rates. With 8 candidate definitions of improvement remaining, we tested to see which were easiest to use and were best in accord with rheumatologists' impressions of improvement.
RESULTS: The following definition of improvement was selected: 20% improvement in tender and swollen joint counts and 20% improvement in 3 of the 5 remaining ACR core set measures: patient and physician global assessments, pain, disability, and an acute-phase reactant. Additional validation of this definition was carried out in a comparative trial, and the results suggest that the definition is statistically powerful and does not identify a large percentage of placebo-treated patients as being improved.
CONCLUSION: We present a definition of improvement which we hope will be used widely in RA trials.

Abstract/Text: OBJECTIVE: The development and validation of Modified Disease Activity Scores (DAS) that include different 28-joint counts.
METHODS: These scores were developed by canonical discriminant analyses and validated for criterion, correlational, and construct validity. The influence of disease duration on the composition of the DAS was also investigated.
RESULTS: No influence of disease duration was found. The Modified DAS that included 28-joint counts were able to discriminate between high and low disease activity (as indicated by clinical decisions of rheumatologists).
CONCLUSION: The Modified DAS are as valid as disease activity scores that include more comprehensive joint counts.

Abstract/Text: OBJECTIVE: To investigate whether rheumatoid arthritis (RA) and psoriatic arthritis (PsA) can be differentiated in the early stages of the disease (duration of symptoms ≤1 year) on the basis of magnetic resonance imaging (MRI) features of the hand and wrist.
MATERIAL AND METHODS: Twenty early RA and 17 early PsA patients with symptomatic involvement of the wrist and hand joints and inconclusive radiographic studies were examined prospectively with contrast-enhanced MRI. Images were evaluated in accordance with the Outcome Measures in Rheumatology Clinical Trials recommendations.
RESULTS: Certain MRI features, such as the presence of enthesitis or extensive diaphyseal bone marrow edema, were observed exclusively in PsA (P = 0.0001). These distinctive findings were present in nearly 71% (12/17) of PsA patients. Diffuse and, in some cases, pronounced soft-tissue edema spreading to the subcutis was also seen more frequently in patients with PsA (P = 0.002). There were no significant differences in the frequency of synovitis, bone erosions, subchondral bone edema, or tenosynovitis between the 2 groups. However, in RA extensor tendons were involved more often than the flexor tendons, whereas in PsA the opposite was observed (P = 0.014). With respect to the discriminatory power of the different MRI findings examined, only the presence of enthesitis or diaphyseal bone edema and, to a lesser extent, the pattern of hand tendon involvement and the presence of soft-tissue edema accurately differentiated PsA from RA (all these features achieved accuracies greater than 0.70).
CONCLUSIONS: We observed significant differences in the MRI findings of the hand and wrist that can help to distinguish between RA and PsA in the early stages of disease. This imaging method could help to assist in the differential diagnostic process in selected patients in whom diagnosis cannot be unequivocally established after conventional clinical, biochemical, and radiographic examinations.

Copyright © 2012 Elsevier Inc. All rights reserved.

Abstract/Text: OBJECTIVE: The 1987 American College of Rheumatology (ACR; formerly, the American Rheumatism Association) classification criteria for rheumatoid arthritis (RA) have been criticized for their lack of sensitivity in early disease. This work was undertaken to develop new classification criteria for RA.
METHODS: A joint working group from the ACR and the European League Against Rheumatism developed, in 3 phases, a new approach to classifying RA. The work focused on identifying, among patients newly presenting with undifferentiated inflammatory synovitis, factors that best discriminated between those who were and those who were not at high risk for persistent and/or erosive disease--this being the appropriate current paradigm underlying the disease construct "rheumatoid arthritis."
RESULTS: In the new criteria set, classification as "definite RA" is based on the confirmed presence of synovitis in at least 1 joint, absence of an alternative diagnosis that better explains the synovitis, and achievement of a total score of 6 or greater (of a possible 10) from the individual scores in 4 domains: number and site of involved joints (score range 0-5), serologic abnormality (score range 0-3), elevated acute-phase response (score range 0-1), and symptom duration (2 levels; range 0-1).
CONCLUSION: This new classification system redefines the current paradigm of RA by focusing on features at earlier stages of disease that are associated with persistent and/or erosive disease, rather than defining the disease by its late-stage features. This will refocus attention on the important need for earlier diagnosis and institution of effective disease-suppressing therapy to prevent or minimize the occurrence of the undesirable sequelae that currently comprise the paradigm underlying the disease construct "rheumatoid arthritis."