Background: Several studies have shown that an elevated heart rate is associated with an increased risk of ischaemic heart disease. The aim of this study was to examine the relationship between heart rate, blood pressure, blood lipids and other cardiovascular risk factors in middle-aged men.
Methods: A total of 7735 men, aged 40-59 years at screening, were selected at random from one of the general practices in each of the 24 towns participating in the cross-sectional (screening) phase of the British Regional Heart Study. Blood pressure and levels of blood lipids (serum total cholesterol, high-density-lipoprotein (HDL) cholesterol and triglycerides) and blood glucose were measured.
Results: All men with pre-existing evidence of ischaemic heart disease and those on regular antihypertensive treatment were excluded from the analysis. In the remaining 5597 men, heart rate showed a strong positive correlation with cigarette smoking and body-mass index and decreased significantly at higher levels of physical activity and FEV1 (forced expiratory volume in 1 s). These associations remained significant after adjustment for each other. Age, alcohol intake and social class were not independently associated with heart rate. There was a significant positive association between heart rate and systolic and diastolic blood pressures, levels of blood cholesterol, triglycerides and blood glucose and a significant inverse association between heart rate and HDL-cholesterol levels, even after adjusting for the above confounding factors. After further adjustment for each of the other physiological variables, heart rate remained independently associated with diastolic and systolic blood pressures and levels of triglycerides and blood glucose. The relationship between heart rate and levels of total cholesterol and HDL cholesterol appeared to be secondary to its association with triglyceride levels. The association between body-mass index and heart rate diminished after further adjustments for systolic blood pressure, suggesting that the primary effect of body weight is on blood pressure rather than on heart rate.
Conclusion: Our findings indicate that elevated heart rate is associated with hypertension and with an atherogenic lipoprotein profile and support the suggestion that disturbance of the autonomic nervous system may underlie these associations.