Relapse Outcomes Following csDMARD Monotherapy Tapering Versus Discontinuation in Rheumatoid Arthritis Patients in Sustained Remission: A Retrospective Cohort Study

Objective/Aim: Sustained remission (SR) has become increasingly achievable in rheumatoid arthritis (RA), but the optimal strategy for abrupt tapering or discontinuing conventional synthetic disease-modifying antirheumatic drugs (csDMARDs) remains uncertain. This study aimed to compare relapse outcomes following csDMARD abrupt tapering versus discontinuation in RA patients maintaining SR and to identify potential predictors of relapse. Methods: We conducted a retrospective cohort study of 101 RA patients fulfilling the 2010 American College of Rheumatology (ACR)/European Alliance of Associations for Rheumatology (EULAR) classification criteria and maintaining SR defined as a Disease Activity Score in 28 joints using C-reactive protein (DAS28-CRP <2.6 for ≥12 months) on csDMARD monotherapy between January 2019 and January 2024. Patients were categorised into abrupt tapering ( n = 40; a single-step 50% dose reduction) and discontinuation ( n = 61) groups. Patients were followed for a median of 48 months (interquartile range [IQR]: 24–70 months) to assess relapse. Relapse was defined as DAS28-CRP >2.4 confirmed within four weeks. Kaplan-Meier and Cox regression analyses assessed relapse-free survival and predictors of relapse. Propensity score matching was applied to minimise confounding. Results: During a median 48-month follow-up, relapse occurred in 44 patients (43.6%): 16 (40.0%) in the abrupt tapering group and 28 (45.9%) in the discontinuation group ( P = .55). Relapse-free survival did not differ significantly (hazard ratio [HR], 1.18, 95% CI 0.64–2.18, P = .60). No demographic, serologic or disease-related factor independently predicted relapse. Conclusions: Abrupt tapering and discontinuation of csDMARD monotherapy yielded comparable relapse outcomes in RA patients maintaining SR. These findings suggest that relapse risk is governed more by immunologic stability than by the de-escalation method. Patient preference and shared decision-making can guide csDMARD withdrawal in clinical practice.