Remission of rheumatoid arthritis in clinical practice: application of the American College of Rheumatology/European League Against Rheumatism 2011 remission criteria.

OBJECTIVE: To describe use of the American College of Rheumatology/European League Against Rheumatism (ACR/EULAR) rheumatoid arthritis (RA) remission criteria in clinical practice. METHODS: Remission was examined using data on 1,341 patients with RA (91% men) from the US Department of Veterans Affairs RA (VARA) registry (total of 9,700 visits) and 1,153 patients with RA (25.8% men) in a community rheumatology practice (Arthritis and Rheumatology Clinics of Kansas [ARCK]) (total of 6,362 visits). Cross-sectional and cumulative probabilities were studied, and agreement between the various remission criteria was assessed. Aspects of reliability of the criteria were determined using Boolean-based definitions, as well as the Clinical Disease Activity Index (CDAI) and Simplified Disease Activity Index (SDAI) scoring methods proposed by the ACR/EULAR joint committee. RESULTS: When the 3-variable ACR/EULAR definition of remission recommended for use in community practice (swollen and tender joint counts ≤1, and visual analog scale score for patient's global assessment of disease activity ≤1) was applied, cross-sectional remission was 7.5% (95% confidence interval [95% CI] 6.4, 8.7%) for ARCK and 8.9% (95% CI 7.9, 9.9%) for VARA, and cumulative remission (remission at any observation) was 18.0% (for ARCK) and 24.4% (for VARA), over a mean followup of ∼2.2 years. Addition of the erythrocyte sedimentation rate or C-reactive protein level to the criteria set reduced remission to 5.0-6.2%, and use of the CDAI/SDAI increased the proportions to 6.9-10.1%. Moreover, 1.8-4.6% of the patients met remission criteria at ≥2 visits. Agreement between criteria definitions was good, as assessed by kappa statistics and Jaccard coefficients. Among patients in remission, the probability of a remission lasting 2 years was 6.0-14.1%. Among all patients, the probability of a remission lasting 2 years was <3%. Remission status and examination results for each patient varied substantially among physicians, as determined by multilevel analyses. CONCLUSION: Cross-sectional remission occurred in 5.0-10.1% of the patients in these cohorts, with cumulative remission being 2-3 times greater; however, long-term remission was rare. Problems with reliability and agreement limit the usefulness of these criteria in the individual patient. However, the criteria can be an effective method for measuring clinical status and treatment effect in groups of patients in the community.

Is fatigue an inflammatory variable in rheumatoid arthritis (RA)? Analyses of fatigue in RA, osteoarthritis, and fibromyalgia.

OBJECTIVE: To investigate whether fatigue is an inflammatory (rheumatoid arthritis; RA) variable, the contributions of RA variables to fatigue, and the levels of fatigue in RA compared with osteoarthritis (OA) and fibromyalgia (FM). METHODS: We studied 2096 RA patients, 1440 with OA, and 1073 with FM in a clinical setting, and 14,607 RA, 3173 OA, and 2487 patients with FM in survey research. We partitioned variables into inflammatory and noninflammatory factors and examined variable contribution to fatigue (0-10 visual analog scale). RESULTS: Factor analysis identified Disease Activity Score-28 (DAS28) and swollen (SJC) and tender joint count (TJC) as a physician-inflammation factor, and patient global assessment, pain, Health Assessment Questionnaire, and fatigue as patient components. Fatigue demonstrated weak correlations with erythrocyte sedimentation rate (ESR; r = 0.071) and SJC (r = 0.112), weak to fair correlations with TJC (r = 0.294), physician global assessment of RA activity (r = 0.384), and DAS28 (r = 0.399), but strong correlation with patient global assessment of severity (r = 0.567). In hierarchical regression analysis, patient global explained 43.1% of DAS28 fatigue variance; when SJC, TJC, and ESR were entered, the explained variance increased to 43.7%. In reverse order, SJC, TJC, and ESR explained 9.2% of the variance, but explained variance increased to 43.7% when patient global was added. The mean clinic fatigue scores were RA 4.9, OA 4.8, FM 7.6; mean survey scores were RA 4.5, OA 4.4, FM 6.3. Adjusted for age and sex, RA and OA fatigue scores were not significantly different. CONCLUSION: Inflammatory components of the DAS28 contribute minimally to fatigue. RA and OA fatigue levels do not differ. Fatigue is not an inflammatory variable and has no unique association with RA or RA therapy.

The problem of rheumatoid arthritis disease activity and remission in clinical practice.

OBJECTIVE: To investigate the results and feasibility of available scales to measure minimal disease activity (MDA) and remission in rheumatoid arthritis (RA) in the clinic. METHODS: We studied 849 consecutive patients with RA seen in a community rheumatology practice for routine RA care by 4 rheumatologists, beginning in March 2007 and ending in August 2007. Patients and physicians completed a simple form at each visit. We calculated the Disease Activity Score 28 (DAS28), Clinical Disease Activity Index (CDAI), physician assessment of global activity, and the Patient Activity Scale (PAS-II). From these we calculated remission and MDA prevalence in this community practice. RESULTS: The DAS28 could not be determined in more than 50% of patients because of referring physician and insurance company restrictions. Remission prevalences differed by assessment method: DAS28 28.5%, CDAI 6.5%-8.1%, physician global 12.5%, PAS 13.7%. MDA was 26.9% using the American College of Rheumatology core set variables, 34.7% using the DAS28, and 26.8% using the PAS-II. The kappa statistic was only fair (0.2 to 0.4) for most comparisons between assessment methods. No significant differences were noted for remission and MDA according to biologic therapy. CONCLUSION: The CDAI and/or physician global and PAS-II are simple acceptable ways to measure RA activity in the clinic, but results differ strikingly according to method. Further standardization appears to be required for full implementation of the CDAI. Caution is urged before using these methods for regulatory purposes.