0548 Position-dependent obstructive sleep apnea and the cardiovascular risks

Abstract Introduction Position dependent obstructive sleep apnea (PdOSA) is highly prevalent, but the implication of PdOSA in cardiovascular (CV) outcomes has not been studied. We hypothesized that associated with lower risk future CV events than those without PdOSA. Methods included patients who underwent diagnostic polysomnography (PSG) at a single academic center. The study ≥2 hours total time, 30 minutes both supine and non-supine sleep, OSA (apnea hypopnea index [AHI]≥5/hr). defined as either POSA (overall AHI≥5/hr accompanied by AHI (sAHI) least twice high (ns-AHI)), or ePOSA (POSA criteria + ns-AHI < 5/hr (i.e., normalized)). Blood pressure (BP) was derived averaging multiple measures clinic BP within 1 year PSG. All were followed up to 11 years identify incident (including acute coronary syndrome, stroke, new heart failure). examined association logistic regression, adjusting for age, sex, race, BMI, systolic BP, severity (mild [AHI 5-15] vs. moderate severe [≥15]). Results A 1750 (mean age: 54 years, female 60%) included. present 47% 23% cohort. Patients less obese had compared ePOSA. (systolic 128.8 vs 131.2 mmHg, p=0.003) Over median 8.3 follow-up, 340 occurred. In multivariable analysis, odds (OR 0.8, 95% CI [0.64-0.99], p=0.044; OR 0.69 [0.52-0.89], p=0.0061, respectively). Analysis stratified showed only mild 0.67 [0.48-0.94], p=0.021). Conclusion Among OSA, more favorable benefit appears be limited OSA. Future studies should compare risks between Support (if any)