Objectives
To examine whether the association of resting heart rate (RHR) with all-cause mortality and/or cardiovascular disease (CVD) differs among younger and older subjects.
Design
Prospective cohort.
Setting
Community in Beijing, China.
Participants
Individuals aged 40 and older without CVD at baseline (N=6209).
Measurements
Trained investigators interviewed participants using a standard questionnaire to obtain information on demographic characteristic, medical history and life style risk factors in 1991. RHR was evaluated according to the following quartiles: <72, 72 to 76, 76 to 84, ≥84 beats/min. Cox regression model was used to assess the association of RHR with all-cause mortality and CVD events.
Results
During a mean follow-up of 8.3 years, 840 subjects died and 676 subjects suffered from CVD. In older subjects (≥60 years old), higher RHR was associated with both all-cause mortality (P trend <0.001) and CVD events (P trend=0.002). However, the associations of RHR with all-cause mortality and CVD events in the younger participants (<60 years old) were not significant (both P trend >0.05). There were significant modifying effects of age on the association of RHR with both all-cause mortality and CVD events ( P interaction <0.001 and = 0.002, respectively). After exclusion of individuals who died (n=100) or suffered from CVD (n=45) during the first 2 years of follow-up, similar results were observed.
Conclusion
Elevated RHR appears to be an independent determinant of both all-cause mortality and CVD events in older subjects but not in younger people.