Risk of obstructive sleep apnoea in patients with rheumatoid arthritis: a nationwide population-based retrospective cohort study

Objective: Sleep disorders are prevalent medical disorders in patients with rheumatoid arthritis (RA). However, whether patients with RA are at an increased risk of developing obstructive sleep apnoea (OSA) is unclear. Design: Using population-based retrospective cohort study to examine the risk of OSA in patients with RA. Setting: We used claims data of the National Health Insurance Research Database (NHIRD) of Taiwan. Participants: We identified a RA cohort with 33 418 patients newly diagnosed in 2000-2010 and a randomly selected non-RA comparison cohort with 33 418 individuals frequency matched by sex, age and diagnosis year. Primary and secondary outcome measures: Incident OSA was estimated by the end of 2011. The HRs of OSA were calculated using the Cox proportional hazards regression analysis. Results: The overall incidence rate of OSA was 75% greater in the RA cohort than in the non-RA cohort (3.04 vs 1.73/10 000 person-years, p < 0.001), with an adjusted HR (aHR) of 1.75 (95% CI 1.18 to 2.60). Stratified analyses by sex, age group and comorbidity revealed that the incidence rates of OSA associated with RA were higher in all subgroups. Conclusions: This population-based retrospective cohort study suggested that patients with RA should be monitored for the risk of developing OSA.