Sex-Related Differences in Dispensation of Rheumatic Medications in Older Patients With Inflammatory Arthritis: A Population-Based Study

Objective The aim of our study was to compare dispensation of rheumatic medications between older male and female patients with early rheumatoid arthritis (RA) and psoriatic arthritis (PsA). Methods This retrospective cohort study was performed using health administrative data from Ontario, Canada (years 2010-2017), on patients with incident RA and PsA, who were aged ≥ 66 years at the time of diagnosis. Yearly dispensation of rheumatic drugs was compared between older male and female patients for 3 years after diagnosis using multivariable regression models, after adjusting for confounders. The groups of drugs included in the analysis were disease-modifying antirheumatic drugs (DMARDs) classified as conventional synthetic DMARDs (csDMARDs) and advanced therapy (biologic DMARDs and targeted synthetic DMARDs), nonsteroidal antiinflammatory drugs (NSAIDs), opioids, and oral corticosteroids. Results were reported as odds ratios (ORs) with 95% CIs. Results We analyzed 13,613 patients (64% female) with RA and 1116 patients (57% female) with PsA. Female patients with RA were more likely to receive opioids (OR 1.39, 95% CI 1.22-1.58 to OR 1.51, 95% CI 1.32-1.72) and NSAIDs (OR 1.14, 95% CI 1.04-1.25 to OR 1.16, 95% CI 1.04-1.30). Dispensation of DMARDs showed no sex difference in either group. Subgroup analyses showed more intense use of advanced therapy in the RA cohort and of csDMARDs in the PsA cohort when patient and physician sex was concordant. Conclusion This study did not identify any sex difference in the use of DMARDs among older patients with RA and PsA. The reasons for the higher use of opioids and NSAIDs among female patients with RA warrant further research.