Abstract
Elevated resting heart rate (HR) is associated with hypertension in addition to or similar to increased incidence of cardiovascular morbidity and mortality. Subjects with high HR exhibit the characteristic features of insulin resistance syndrome. Sympathetic overactivity underlies this clinical condition. However, the true mechanism of high HR is unclear. We examined the relation between resting HR and age, gender, traditional coronary risk factors, and white blood cell (WBC) count in urban Japanese. The study population comprised 2, 736 people aged 40, 50, and 60 years old. Multiple regression analysis of the total population showed that gender (p < 0.001), systolic and diastolic blood pressure (SBP, DBP; p < 0.001), serum triglycerides (TG; p < 0.001), fasting plasma glucose (FPG; p < 0.001) and WBC count (p < 0.001) had significant correlations with HR in the total population. Exercise was negatively correlated with HR (p < 0.001). In the age-adjusted profiles, gender (p < 0.001), SBP (p < 0.001), FPG (p < 0.001, p < 0.01 at age 40 years) and WBC count (p < 0.001) showed a significant correlation with HR among all three age groups. A negative association between HDL cholesterol (HDLc) and HR was seen at age 60 years (p < 0.01). A negative correlation between exercise and HR was seen at age 40 years (p < 0.001) and age 50 years (p < 0.01). It is suggested that the WBC count is one of the important determinants of resting HR regardless of age. Further studies are necessary to clarify the link between HR, coronary risk factors, and chronic infections.
