Continuous positive pressure therapy usage and incident stroke in patients with obstructive sleep apnea: A nationwide population- based cohort study.

INTRODUCTION: Continuous positive airway pressure (CPAP) is the main treatment for obstructive sleep apnea (OSA). To date, the link between CPAP usage and incident stroke has been inconsistent. OBJECTIVE: This nationwide population study is designed to examine the effect of CPAP on stroke incidence in OSA patients. METHODS: Using Taiwan's National Health Insurance Research Database (NHIRD), this study collected data from 4,275 OSA patients diagnosed between 2000 and 2011 and divided them into two groups according to whether they received CPAP treatment. After matching baseline demographics and comorbidities, both cohorts contained 959 OSA patients and were followed to a newly diagnosed stroke or until the end of 2013. Cox regression analysis was performed to examine the incidence of stroke between patients with OSA receiving CPAP or no CPAP treatment RESULTS: CPAP treatment for OSA patients predicted a lower incidence rate (3.41 vs. 5.43 per 1,000 person-years) and tended to protect against the development of stroke (hazard ratio (HR): 0.68, 95% confidence interval (95% CI): 0.38-1.23) compared to those without CPAP treatment, but the estimate was not statistically significant. Similar results were also observed by dividing stroke into ischemic (2.65 vs. 4.30 per 1,000 person-years; HR: 0.67, 95% CI: 0.35-1.31) or hemorrhagic origin (0.76 vs. 1.12 per 1,000 person-years; HR: 0.67, 95% CI: 0.19-2.40). CONCLUSIONS: It is possible that treatment with CPAP might be beneficial for protection against stroke, but this conclusion should be interpreted with caution. Future studies with satisfactory CPAP quality and duration are needed to validate this observation.