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 incident patients with RA and PsA, who were 66 years or older at the time of diagnosis. Yearly dispensation of rheumatic drugs was compared between older male and female patients for three years after diagnosis using multivariable regression models, after adjusting for confounders. The groups of drugs included in the analysis were DMARDs classified as conventional DMARDs (csDMARDs) and advanced therapy (biologic DMARDs (bDMARDs) and targeted synthetic DMARDs (tsDMARDs)), NSAIDs, opioids and oral corticosteroids. Results were reported as Odds Ratios with 95% Confidence Intervals (CI).

RESULTS: We analyzed 13,613 patients (64% females) with RA and 1,116 patients (57% females) with PsA. Female RA patients were more likely to receive opioids (OR [95% CI] 1.39 [1.22-1.58] to 1.51 [1.32-1.72]) and NSAIDs (OR [95% CI] 1.14 (1.04-1.25) to 1.16 [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 use of DMARDs among older RA and PsA patients. Reasons for the higher use of opioids and NSAIDs among female RA patients warrants further research.