Epidemiology of high blood pressure and obesity.

The relationship between bodyweight and arterial pressure was first discovered early this century. More recently, epidemiological studies have confirmed the correlation between bodyweight and blood pressure in both adults and children. Serum cholesterol levels, blood glucose levels, uric acid levels and blood pressure increase with increasing bodyweight. In the presence of androgens, upper body obesity, caused by excessive intake of calories, increases cardiovascular risk factors, probably as a result of hyperinsulinaemia. The activity of Na+/K(+)-ATPase in the cells of obese subjects is reduced in a way that may be genetically determined, or may be mediated by changes in plasma insulin levels or a natural inhibitor of Na+/K(+)-ATPase. In vitro studies have shown that the potency of a non-ouabain inhibitor of Na+/K(+)-ATPase is enhanced by the presence of insulin. This may result in vascular smooth muscle having increased reactivity to pressor agents. A knowledge of cellular membrane transport may lead to a better understanding of the epidemiology of obesity-related hypertension.