Abstract 18481: Paroxysmal Atrial Fibrillation and Sleep Apnea: Diurnal Patterning of Autonomic Function and Influence of CPAP Therapy

Abstract

Introduction: Autonomic nervous system (ANS) dysfunction is implicated in sleep-disordered breathing (SDB) and atrial fibrillation (AF). Hypothesis: We hypothesize that ANS measures of heart rate variability (HRV) exhibit diurnal differences in paroxysmal AF(PAF) relative to SDB severity and is impacted by continuous positive airway pressure (CPAP). Methods: Data from the Sleep Apnea and Atrial Fibrillation Biomarkers and Electrophysiologic Atrial Triggers (SAFEBEAT) study including PAF (7-24 day ECG monitoring), concomitant actigraphy and SDB from polysomnography at baseline and 3-months post-CPAP were analyzed. Linear mixed-effects models were used to assess SDB (apnea hypopnea index (AHI), hypoxia (%sleep time with SaO2<90% and nadir SaO2) and diurnal average HRV (frequency domain (sympathovagal)): low-frequency range (LF), high-frequency range (HF), LF/HF; time domain: mean of normal RR interval (MNN), standard deviation of NN intervals (SDNN), SD1(Poincare plot standard deviation) and effect of 3-month CPAP. Results: In 44869 five-minute epochs from 109 participants with SDB and PAF, during wakefulness, associations of AHI and LFP, nadir SaO2 with sympathovagal measures (LFP, LHR) and time domain measures (SDNN, SD2) were observed. A sleep-wake significant interaction was observed with all HRV measures and stronger associations in wake than sleep. Baseline to follow-up CPAP time domain measures were increased during wakefulness (MNN, SDNN, RMSSD, CV, SD1, and SD2) and increased during sleep (MNN, SD2, LHR). Conclusions: Diurnal variation of autonomic measures in moderate to severe SDB was observed and association with SDB severity was more pronounced during wakefulness; CPAP influenced autonomic function. These findings in earlier onset AF may contribute to electrophysiological remodeling with implications for ANS-specific chronobiology in SDB.