Abstract 10377: Determinants of Longitudinal Change in Heart Rate Variability in the General Population: The Atherosclerosis Risk in Communities (ARIC) Study
Background: Low heart rate variability (HRV) is associated with an increased risk of death in the general population. Despite the prognostic significance, the factors that determine longitudinal change in HRV over time remain unclear. We aimed to identify determinants of longitudinal change in HRV in ARIC, a biracial community-based cohort study.
METHODS: We included 4,522 subjects (aged 53.0 ± 5.5 years at baseline, 58% female, 16% black) without diabetes, hypertension, and cardiovascular disease (CVD) in 1987-89 (baseline or visit 1), and with HRV measured at visit 1 and 1996-98 (visit 4). HRV data (standard deviation of all normal RR intervals [SDNN]) were obtained from 2 minute and 6-minute rhythm strips at visits 1 and 4, respectively. An adjustment equation was applied to the 6-minute data to make them comparable to the 2-minute data. Longitudinal change in SDNN was computed as the ratio of SDNN at visit 4 to SDNN at visit 1. We used multiple linear regression to assess association of baseline clinical and socio-demographic variables, and incident CVD with longitudinal change in SDNN.
RESULTS: The mean time between visits 1 and 4 was 8.9 ± 0.3 years. The mean SDNN at visits 1 and 4 were 39.3 ± 19.4 and 32.1 ± 15.5 ms, respectively. Smoking and higher heart rate were associated with greater longitudinal decline in SDNN. Older age, black race, and light alcohol consumption (<41 grams of alcohol/week) were associated with less longitudinal decline in SDNN (Table).
Conclusions: In individuals free of CVD in the general population, modifiable risk factors that favor less longitudinal decline in HRV include light alcohol consumption (vs. no alcohol consumption) and smoking abstinence. Further studies to confirm whether these lifestyle behaviors are associated with less longitudinal decline in HRV are warranted.
- © 2013 by American Heart Association, Inc.