Effect of resting heart rate on the risk of all-cause death in Chinese patients with hypertension: analysis of the Kailuan follow-up study

Objective Previous studies have shown that an elevated heart rate is associated with a higher risk of cardiovascular events. This study aimed to prospectively examine the relationship between resting heart rate (RHR) and all-cause mortality in Chinese patients with hypertension. Design An observational, prospective and population-based cohort study. Setting The Kailuan cohort study was conducted in Tangshan City in northern China. Participants We enrolled 46 561 patients who did not receive beta-blocker treatment and were diagnosed with hypertension for the first time during an employee health examination in Kailuan Group in 2006 and 2008. Outcome The primary outcome of this study was all-cause mortality. Methods The patients in this study were followed for 9.25 +/- 1.63 years. All patients were followed up face to face every 2 years. According to the distribution of RHR in the study population, RHR was categorised into five groups on the basis of quintiles: Q1: RHR <= 68 beats per minute (bpm); Q2: RHR >68 and >72 bpm; Q3: RHR >72 and <= 76 bpm; Q4: RHR >76 and <= 82 bpm; Q5: RHR >82 bpm. Cox proportional hazards model, which was adjusted for traditional risk factors, was used. Results During follow-up, 4751 deaths occurred. After adjustment for potential confounders, restricted cubic spline regression showed that the risk of all-cause mortality increased with heart rate. In multivariate Cox regression analyses adjusted for age, sex and major covariates, the HR for all-cause mortality was 1.31 (95% CI 1.27 to 1.33) in the highest quintile group (Q5) compared with the lowest quintile group (Q1). Conclusion An increase in RHR is a long-term risk factor of all-cause mortality in Chinese patients with hypertension.