Abstract 15380: Association of Change in Body Mass Index With Premature Atrial Contractions Frequency and Atrial Fibrillation in Older Age: The Atherosclerosis Risk in Communities (ARIC) Study

Abstract

Introduction: The proportions of obese and aging adults are rapidly growing. While obesity and advancing age are associated with atrial fibrillation (AF), data are limited on weight change in the elderly as a risk factor for premature atrial contractions (PACs)—which are known to precede AF—or AF. Hypothesis: Compared to a stable body mass index (BMI) over time, increasing BMI will be associated with a higher PAC frequency and AF in elderly participants in ARIC. Methods: We included N=2,070 ARIC participants [age mean ± SD 79 ± 4.5 years, 59% female] without known AF who attended visit 6 and wore an ambulatory ECG-monitoring device (Zio XT® Patch, iRhythm Technologies Inc.) for ≥48 hours. BMI change was defined as change between V5 (2011-13) and V6 (2016-17) and was categorized into 4 groups: >10% decrease, 2 to 10% decrease, -2 to 2% change (stable BMI) and > 2% increase. PAC frequency was defined as percent of beats that are PACs. Linear regression was used to evaluate the association between BMI change and % PAC. Incident AF was ascertained after V6 through 2018 from hospital discharge codes and death certificates. Logistic regression was used to evaluate the association between BMI change and incident AF. Results: Median PACs per hour were 8.84. Participants with >2% BMI increase had 0.35% (95% CI: 0.06%-0.64%) higher frequency of PACs compared to those with stable BMI after multivariable adjustment (Table). After a mean (SD) follow-up of 19 (7) months, there were 82 incident AF cases. Compared to stable BMI, both >2% BMI increase and 2 to 10% decrease were nonsignificantly associated with higher odds of AF compared with stable BMI after multivariable adjustment (Table). Conclusion: Increasing BMI in the elderly is associated with higher PAC frequency and is nonsignificantly associated with higher odds of AF compared to stable BMI. This finding suggests that weight management, which is currently emphasized in middle age, may also apply in late-life to prevent atrial arrhythmias.