Polysomnographic Heart Rate Variability Indices and Atrial Ectopy Associated With Incident Atrial Fibrillation Risk in Older Community-Dwelling Men

Objectives The authors hypothesized that polysomnogram-based heart rate variability autonomic function biomarkers are associated with incident atrial fibrillation (AF) and these associations are modified by measures of sleep-disordered breathing. Background Autonomic dysfunction contributes to AF. Methods A total of 2,350 participants of a multicenter prospective study (Outcomes of Sleep Disorders in Older Men Study) without baseline AF underwent sleep studies with incident adjudicated AF follow-up (8.0 ± 2.6 years). Cox proportional hazard models were used to analyze sleep study–electrocardiogram spectral heart rate variability indices (low- and high-frequency power [LF/HF]) and time domain indices (mean of normal to normal beats and short- and long-term variability) and premature atrial contractions and incident AF (hazard ratio and 95% confidence interval). Statistical interactions between heart rate variability and sleep-disordered breathing were examined. Models were adjusted for age, race, body mass index, waist circumference, cardiac medications, comorbid diseases, alcohol use, and study site. Results Lower LF/HF and lower LF were associated with higher AF incidence (LF/HF Q1 vs. Q4: 1.46; 1.02 to 2.08; LF Q1 vs. Q4: 1.46; 1.02 to 2.10). Higher short- and long-term variability was associated with an increased risk of AF (p trend = 0.028). The highest premature atrial contractions quartile had a 3-fold increased AF risk (2.99; 1.94 to 4.62) compared with the lowest quartile. A significant interaction of obstructive apnea was observed in the LF-AF relationship (p = 0.045). Conclusions Sleep-related reduced sympathovagal balance (LF/HF) and increased atrial ectopy are independently associated with future AF, a relationship modified by obstructive apnea.