Abstract 15060: Resting Heart Rate, Heart Rate Variability and Incident Atrial Fibrillation: Results From the Multi-Ethnic Study of Atherosclerosis (MESA)

Introduction: Evidence suggests an association between augmentation of sympathetic tone or alteration of parasympathetic activity and atrial fibrillation (AF). Hypothesis: We hypothesized that lower and higher heart rate and heart rate variability (HRV) as measures of autonomic dysregulation are associated with incident AF. Methods: The MESA cohort consisted of participants who were free of clinically-recognized cardiovascular disease at baseline. We used three standard 10-second, 12-lead electrocardiograms to measure heart rate, the standard deviation of normal-to-normal intervals (SDNN), and the root mean square of successive differences in RR intervals (RMSSD). Incident AF was identified using inpatient and outpatient diagnostic codes, study electrocardiograms, and Medicare claims. Participants with AF at baseline, and those who were on a beta-blocker or any AV nodal agent were excluded. Cox proportional hazards models adjusted for sociodemographic characteristics and known clinical risk factors for AF were used to examine the association of baseline heart rate, and log transformed SDNN and RMSDD with incident AF. Results: Of 6104 participants enrolled in this study, 498 (8.1%) developed AF over a median follow-up of 10.1 ± 2.6 years. In unadjusted analysis, heart rate ≤51bpm (10 th percentile) and ≥ 76bpm (90 th percentile) were associated with incident AF (reference group: heart rate > 51 bpm and Conclusions: In a multi-ethnic population, the association of autonomic dysregulation (as reflected by low HRV) and sinus node dysfunction (as reflected by low baseline heart rate) with incident AF was not independent of cardiovascular risk factors. Only higher heart rate was independently associated with incident AF.