Long-term association of 15-second heart rate variability with cardiovascular events

Abstract

Abstract Heart rate variability (HRV) is an established cardiac autonomic marker with predictive value in cardiac patients. Ultra-short HRV (usHRV) derived from 10–30 sec ECGs can be measured at scale using standard and wearable ECGs, but its association with cardiovascular events in the general population is undetermined. We aimed to validate usHRV measured using 15-second ECGs (using RMSSD, SDSD and PHF indices) and investigate its association with atrial fibrillation (AF), major adverse cardiac events (MACE), stroke and mortality in individuals without cardiovascular disease. In the National Survey for Health and Development (n = 1,337 participants), agreement between 15-second and 6-minute HRV, assessed with correlation analysis and Bland-Altman plots, was very good for RMSSD and SDSD and good for PHF. In the UK Biobank (n = 51,628 participants, 64% male, median age 58), after a median follow-up of 11.5 (11.4–11.7) years, incidence of outcomes ranged between 1.7% and 4.3%. Non-linear Cox regression analysis showed that reduced usHRV was associated with all outcomes. Individuals with low usHRV (< 20th percentile) had hazard ratios for outcomes between 1.16 and 1.29, p < 0.05, with respect to the reference group. In conclusion, usHRV from 15-second ECGs correlates with standard short-term HRV and predicts increased risk of cardiovascular events in the general population.