Energy balance and blood-pressure regulation. Update and future perspectives.

The relationship of blood pressure to body weight within populations is well documented: it is also generally accepted that the body mass index, as well as the change in body mass index over time, are predictive of risk for future hypertension. Short-term clinical trials suggest that satisfactory blood-pressure control can be more easily achieved in obese hypertensive subjects by a successful program of weight reduction. On the other hand, the pathophysiological aspects of the association between excessive weight and high blood pressure are still obscure; particularly the putative role of hyperinsulinemia, as well as exaggerated sympathetic activity, need to be confirmed. Recent evidence indicates that upper body fat predominance and low habitual physical exercise may be factors contributing to the increase in blood pressure, but the importance of still other factors, such as associated abnormalities of cell cation transport, has to be further elucidated. From the therapeutic point of view, there is a strong need for controlled trials to confirm feasibility and effectiveness of long-term programs of weight reduction as a means to control hypertension in the obese. Based on these considerations and the enormous potential for primary prevention, the problem of energy balance and blood-pressure regulation stands as a most important issue for future cardiovascular research.