The Effect Size of Fibromyalgia on PG-VAS in Rheumatoid Arthritis Patients. Adjustment Proposal in DAS28-ESR: Letter to the Editor regarding Challa, D.N.V., Crowson, C.S. & Davis, J.M. Rheumatol Ther (2017) 4: 201. doi:10.1007/s40744-017-0063-5

Association of 17 Definitions of Remission with Functional Status in a Large Clinical Practice Cohort of Patients with Rheumatoid Arthritis

Objective.

To compare the association between different remission criteria and physical function in patients with rheumatoid arthritis followed in clinical practice.

Methods.

Longitudinal data from the METEOR database were used. Seventeen definitions of remission were tested: American College of Rheumatology/European League Against Rheumatism (ACR/EULAR) Boolean-based; Simplified/Clinical Disease Activity Index (SDAI/CDAI); and 14 Disease Activity Score (DAS)-based definitions. Health Assessment Questionnaire (HAQ) ≤ 0.5 was defined as good functional status. Associations were investigated using generalized estimating equations. Potential confounders were tested and sensitivity analyses performed.

Results.

Data from 32,915 patients (157,899 visits) were available. The most stringent definition of remission was the ACR/EULAR Boolean-based definition (1.9%). The proportion of patients with HAQ ≤ 0.5 was higher for the most stringent definitions, although it never reached 100%. However, this also meant that, for the most stringent criteria, many patients in nonremission had HAQ ≤ 0.5. All remission definitions were associated with better function, with the strongest degree of association observed for the SDAI (adjusted OR 3.36, 95% CI 3.01–3.74).

Conclusion.

The 17 definitions of remission confirmed their validity against physical function in a large international clinical practice setting. Achievement of remission according to any of the indices may be more important than the use of a specific index. A multidimensional approach, targeted at wider goals than disease control, is necessary to help all patients achieve the best possible functional status.