Objectives: To evaluate the prevalence of clinical remission and minimal disease activity according to the ACR/European League Against Rheumatism (EULAR) remission, DAS-28 <2.6 and minimal disease activity (MDA) criteria, and to compare the extent of residual disease activity with disability in RA patients after 6 months of treatment with anti-TNF.
Methods: In the Dutch Rheumatoid Arthritis Monitoring (DREAM) biologic registry the prevalence of DAS-28 <2.6, MDA and ACR/EULAR remission criteria was assessed. Residual disease activity during MDA or remission was assessed as the percentage of patients with swollen and tender joints, elevated acute-phase reactants and general health on a visual analogue scale (VAS). Disability was evaluated with the HAQ score.
Results: Prevalence of DAS-28 <2.6 was 27%, prevalence of MDA was 34% and ACR/EULAR remission was reached by 6% of patients. Residual disease activity was present mostly in the most lenient criteria and occurred most frequently on the level of swollen joint count and VAS score: at least one swollen joint in DAS-28 <2.6, MDA and ACR/EULAR remission was present in, respectively, 51, 54 and 34% of the patients. VAS >1 occurred in, respectively, 67, 69 and 0% of the patients. Modification of the cut-point of the patient-reported outcome increased the prevalence of ACR/EULAR remission, but also the level of disability.
Conclusion: MDA and DAS-28 <2.6 are reachable treatment targets in RA with anti-TNF, although residual disease activity might still be present. In turn, ACR/EULAR remission criteria leave little residual disease activity, but might be too stringent for use in daily clinical practice due to the strict cut-point in the patient-reported outcome.