Effect of diet and exercise on pulse pressure and cardiac function in morbid obesity: analysis of 24-hour ambulatory blood pressure.

Blood pressure is a major risk factor for cardiovascular events, although the role of pulse pressure, an independent predictor of arterial stiffness, has recently been emphasized. This study examines the baseline relationship between body mass index (BMI) and blood pressure indexes in 215 obese African Americans enrolled in a diet-exercise program. The subject population was 77% female, with a mean +/- SD age of 46.7+/-10.7 years and a mean BMI of 42.5+/-7.5 kg/m2. In addition, the authors prospectively examined the effect of weight loss on cardiovascular parameters in a subset of 25 participants. The results show a closer significant correlation between pulse pressure and BMI (b=1.97 kgm-1; p=0.001) than between systolic blood pressure and BMI (b=1.58 kgm-1; p=0.020). After 3 months of diet and exercise, average reductions were as follows: BMI, 4.2 kg/m2 (p<0.01); systolic blood pressure, 7.2 mm Hg (p<0.01); pulse pressure, 4.8 mm Hg (p<0.01); and cardiac output, 975 mL/min (p<0.01). Compliance index increased by 0.1 mL/mm Hg/m2 (p=0.03). The results highlight the potential value to cardiovascular health of a modest reduction in body weight in obese individuals.