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. TRIAL REGISTRATION NUMBER: ChiCTR-TNC-11001489.