High heart rate - A risk factor for cardiovascular death in elderly men

Objective: To examine the association between heart rate and 12-year incide nce rates of total and cardiovascular death in a cohort of elderly subjects stratified by sex. Subjects and Methods: The study was carried out in 763 white men and 1175 w omen aged 65 years or older who were participating in the Cardiovascular St udy in the Elderly. Subjects were divided into quintiles of heart rate; the top quintile comprised those with a heart rate of greater than 80/min and the bottom quintile, those with a heart rate of less than 64/min. Results: In the men, the number of deaths from cardiovascular causes was si gnificantly increased in those in the top quintile of heart rate (crude rel ative risk, 1.55) but decreased in those in the bottom quintile (crude rela tive risk, 0.65). Similar relationships were found in the women, but the as sociations did not reach statistical significance (all-cause, P =.11; cardi ovascular, P =.15). After adjustment for baseline age, body mass index, hyp ertension, diabetes mellitus, angina or previous myocardial infarction (cor onary heart disease), regular medication, lipid levels, smoking, alcohol in take, forced expiratory volume in 1 second, and other confounders, the rela tive risk for cardiovascular death in the men was 1.38 (95% confidence inte rval, 0.94-2.03) for the subjects in the top quintile of heart rate and 0.8 2 (95% confidence interval, 0.52-1.28) for those in the bottom quintile. In the Cox analysis, predictors of time to cardiovascular death were heart ra te (P<.001), age (P<.001), coronary heart disease (P<.001), clinical heart failure (P=.001), diabetes mellitus (P=.001), hypertension (P=.02), and tri glyceride levels (P=.04), whereas total (P =.20) and high-density lipoprote in-cholesterol (P =.21) levels and smoking (P =.74) were found to be nonsig nificant by the model. The heart rate-cardiovascular death association held true when subjects who died in 2 years after enrollment were excluded (P = .008). Conclusions: An elevated heart rate may be a strong predictor of cardiovasc ular death in elderly men. Conversely, a low heart rate is related to a bet ter outcome in these subjects.