Psoriatic arthritis risk in psoriasis patients prescribed acitretin versus disease-modifying antirheumatic drugs: a nationwide cohort study.

Abstract

To compare the risk of psoriatic arthritis (PsA) in psoriasis (PsO) patients treated with acitretin vs disease-modifying antirheumatic drugs (DMARDs). This retrospective study used Taiwan's National Health Insurance Research Database from 1997 to 2013. Adult PsO patients without PsA prescribed acitretin or DMARDs for ≥30 days within a year were assigned to the acitretin cohort or DMARDs cohort, respectively. Patients in the acitretin cohort prescribed DMARDs for >7 days, or in the DMARDs cohort prescribed acitretin for >7 days, were excluded. Cumulative incidence of PsA were determined within both cohorts using the Kaplan-Meier method. The hazard ratio (HR) comparing acitretin to DMARDs was calculated with Cox regression models, adjusting for demographic and clinical covariates including the use of non-steroidal anti-inflammatory drugs (NSAIDs) and comorbidities. The study included 1,948 patients in each cohort. The 5-year cumulative incidence of PsA in the acitretin cohort was lower than that in the reference cohort (7.52% vs 9.93%; P=0.005), with a more pronounced difference in the subpopulation receiving NSAIDs treatment. However, in subpopulations without NSAIDs treatment, the 5-year cumulative incidence of PsA in the acitretin cohort was comparable to the DMARDs cohort (5.26% vs 6.98%; P = 0.106). Acitretin was not associated with PsA development in PsO (HR 0.83, 95% confidence interval 0.65-1.05). This risk remained consistent regardless of adjustments for NSAID treatment and comorbidities. Other independent risk factors for PsA included female and NSAIDs treatment. Compared with DMARDs, acitretin was not associated with increased PsA risk in PsO patients.