Objective: To investigate in rheumatoid arthritis (RA) the rate and reason of discontinuation of tumour necrosis factor (TNF) antagonists over the past decade.
Methods: RA patients in BIOBADASER 2.0 were stratified according to the start date of their first TNF antagonist into 2000-3, 2004-6 and 2007-9 interval years. Cumulative incidence function of discontinuation for inefficacy or toxicity was estimated with the alternative reason as competing risk. Competing risks regression models were used to measure the association of study groups with covariates and reasons for discontinuation. Association is expressed as subhazard ratios (SHR).
Results: 2907 RA patients were included in the study. Competing risk regression for inefficacy shows larger SHR for patients starting treatment in 2004-6 (SHR 2.57; 95% CI 1.55 to 4.25) and 2007-9 (SHR 3.4; 95% CI 2.08 to 5.55) than for those starting in 2000-3, after adjusting for TNF antagonists, clinical activity and concomitant treatment. Competing risk regression analysis for adverse events revealed no differences across the three time intervals.
Conclusions: In RA, the discontinuation rate of TNF antagonists in the first year of treatment is higher more recently than a decade ago, inefficacy being the main reason for the increased rate. The rate of discontinuation for adverse events has remained stable.