0963 Obstructive Sleep Apnea and Atrial Fibrillation Recurrence: Real-World Analysis of Continuous Positive Airway Pressure Adherence Thresholds

Abstract Introduction Obstructive sleep apnea (OSA) contributes to atrial fibrillation (AF) through intermittent hypoxia, sympathetic activation, and atrial remodeling. Continuous positive airway pressure (CPAP) therapy mitigates these effects, but real-world adherence is inconsistent and the nightly threshold that yields cardiovascular benefit remains uncertain. This study examined the relationship between objective CPAP use and AF recurrence to define a clinically meaningful adherence target for secondary prevention. Methods A retrospective multicenter cohort of adults with polysomnography-confirmed OSA and paroxysmal or persistent AF who initiated CPAP between 2018 and 2024 was analyzed. Device-recorded CPAP data were collected at 90-day intervals. Adherence was classified as high (≥ 4 h/night on ≥ 70 % of nights), moderate (2–3.9 h/night), or low (< 2 h/night). The primary outcome was time to AF recurrence after electrical or pharmacologic cardioversion, verified by electrocardiogram or rhythm monitoring. Multivariable Cox proportional-hazards models adjusted for age, sex, body-mass index, hypertension, diabetes, coronary disease, and baseline apnea–hypopnea index. Sensitivity analyses excluded incomplete follow-up and antiarrhythmic nonadherence. Results High CPAP adherence was associated with a 38 % lower adjusted risk of recurrence compared with low adherence (hazard ratio 0.62, 95 % confidence interval 0.45–0.85; p = 0.002). Among 642 patients (mean age 63 ± 10 years; 41 % female; median apnea–hypopnea index 29 events/h), median follow-up was 18 months. AF recurrence occurred in 38 %. Moderate adherence showed a non-significant trend toward benefit (hazard ratio 0.83, 95 % confidence interval 0.64–1.07). Results were consistent across subgroups defined by OSA severity, cardiovascular comorbidities, and sex. Conclusion Higher CPAP adherence independently predicted lower AF recurrence in patients with OSA. A nightly threshold of ≥ 4 hours appears sufficient for measurable arrhythmia reduction. Integrating adherence-monitoring and behavioral reinforcement into multidisciplinary sleep-cardiology programs may enhance long-term cardiovascular outcomes. Support (if any)