Elevations in time-varying resting heart rate predict subsequent all-cause mortality in older adults

Background: An increased resting heart rate (RHR) has long been associated with unhealthy life. Nevertheless, it remains uncertain whether time-varying measurements of RHR are predictive of mortality in older persons.

Design: The purpose of this study was to assess the relationship between repeated measurements of RHR and risk of death from all causes among older adults.

Methods: We evaluated repeat measurements of resting heart rate among 5691 men and women (aged 65 years or older) enrolled in the Cardiovascular Health Study. RHR was measured annually for six consecutive years by validated electrocardiogram. All-cause mortality was confirmed by a study-wide Mortality Review Committee using reviews of obituaries, death certificates and hospital records, interviews with attending physicians, and next-of-kin.

Results: Of the study cohort, 974 (17.1%) participants died. Each 10 beat/min increment in RHR increased the risk of death by 33% (adjusted hazard ratio, 95% confidence interval (CI) = 1.33, 1.26-1.40). Similar results were observed (adjusted hazard ratio, 95% CI = 2.21, 1.88-2.59) when comparing the upper-most quartile of RHR (mean = 81 beats/min) with the lowest (mean = 53 beats/min). Compared with participants whose RHR was consistently ≤65 beats/min during the study period, the risk of death increased monotonically for each 10 beat/min (consistent) increment in RHR, with adjusted hazard ratios (95% CI) ranging from 1.30 (1.23-1.37) for 75 beats/min to 4.78 (3.49-6.52) for 125 beats/min.

Conclusions: Elevations in the RHR over the course of six years are associated with an increased risk of all-cause mortality among older adults.