Although pulse pressure (PP), heart rate variability (HRV) and baroreflex sensitivity (BRS) have been shown to predict cardiovascular events and mortality in various populations, their relationships have not been clarified. We examined these associations in two separate population-based samples of healthy middle-aged subjects. In population 1, data were obtained from 149 subjects (71 men and 78 women) aged 35-64 (mean 47.7) years, and in population 2, from 214 subjects (88 men and 126 women) aged 40-62 (mean 50.5) years. Increased 24-h ambulatory PP was related to decreased cross-spectral BRS independent of age and gender (beta=-0.28, P