0466 High Frequency Of PLMS Is Associated With Increased Risk Of Incident Adverse Cardiovascular Events And Death Among OSA Patients

Abstract

Introduction: Periodic limb movements of sleep (PLMS) and obstructive sleep apnea (OSA) have both been linked to increased risk of cardiovascular disease (CVD). PLMS are also common among OSA patients, yet little is known about the impact of PLMS on CVD in OSA. Accordingly, we aimed to determine whether PLMS pose a risk for CVD or death among U.S. Veterans with OSA. Methods: Longitudinal analysis of a multi-site, observational U.S. Veteran cohort of men (n=996) diagnosed with OSA (AHI >;=5/ hour) was performed. PLMS and apnea hypopnea index (AHI) were ascertained according to AASM criteria. At enrolment, the following covariates were ascertained: age, ethnicity, body mass index (BMI), smoking, alcohol use, prevalent hypertension, diabetes, coronary artery disease (CAD), stroke, heart failure (HF), atrial fibrillation, renal failure and chronic obstructive pulmonary disease (COPD). Primary outcome (a composite of acute coronary syndrome [ACS], transient ischemic attack [TIA], stroke or death) were assessed at follow-up (4.9 ± 1.9 years). The relationship of PLMS and incident primary outcome was evaluated using unadjusted and adjusted Cox proportional hazards models. Results: Veterans were 59.9 ± 11.3 years old with a BMI of 35.4 ± 7.1 kg/m2. Fifty-five percent had AHI >;=15/hour with median PLMS index (PLMI) of 0/hour and 90th percentile of 42/hour. Prevalent comorbidities were common (hypertension 74%, diabetes 36%, CAD 22%, COPD 32%, renal failure 7%) and 24% of the Veterans suffered an incident primary outcome event. In longitudinal analyses, PLMI >;=42/hour was associated with increased risk of primary outcome (hazard ratio, HR, 95%CI of 2.17 [1.41, 3.36]) and remained significant after adjustment for covariates (noted in methods), HR of 1.49 (1.01, 2.21). AHI was not associated with primary outcome (p-value 0.209). Conclusion: In male Veterans with OSA, high frequency of PLMS is associated with increased risk of incident ACS, stroke, TIA or death, independently of baseline cardiovascular risk, other medical comorbidities or OSA severity.