Prevalence and predictors of achieving sustained remission in psoriatic arthritis. A Swedish nationwide registry study.

Abstract

OBJECTIVE To estimate the prevalence and predictors of sustained remission (SR) in psoriatic arthritis (PsA) patients receiving biologic or targeted synthetic disease-modifying antirheumatic drugs (b/tsDMARDs) in Sweden. METHODS All PsA patients initiating b/tsDMARDs and who were registered in the national Swedish Rheumatology Quality register (SRQ) April 1999-December 2019 were included. Data on disease/treatment characteristics at first b/tsDMARD (baseline) and all subsequent visits were extracted from SRQ. Remission was defined as DAS28CRP≤2.6, DAPSA28≤4 or the evaluator's global assessment of disease activity (EGA) on a scale 0-4 (remission=0), and SR when these criteria persisted during at least two consecutive visits for ≥6 months. Baseline predictors of SR were explored using logistic regression analysis. RESULTS Data on 4.669 PsA patients with 48.773 visits were available. 81% patients achieved DAS28CRP remission ever, and 54% achieved SR at least once. The corresponding percentages for DAPSA28 were 46% and 24%, and for EGA were 69% and 38%, ever reaching remission and SR, respectively. Male sex was positive predictor of reaching SR when measured by DAPSA28 and EGA but not by DAS28CRP. Fewer swollen joints at baseline predicted SR according to all three remission criteria. CONCLUSION A considerable proportion of PsA patients receiving various b/tsDMARDs never achieved remission, and approximately half never achieved SR in this Swedish nationwide registry study. Fewer swollen joints at first b/tsDMARD start increases the likelihood of SR, regardless of remission criteria used. There was still sex difference when measured with DAPSA28 and EGA, with men being more likely to reach SR.