Importance of controlling blood pressure.

Cardiovascular disease is the leading cause of death and disability world-wide. Blood pressure, throughout the range seen in developed countries, is the most important risk factor for cardiovascular disease. Lowering blood pressure within the whole population by lifestyle interventions, such as reducing dietary salt intake and increasing the consumption of fruit and vegetables, will be of great benefit. Blood pressure-lowering trials also demonstrate immense benefits in preventing strokes, heart failure and coronary heart disease. There are no differences in outcome between the different methods used to lower blood pressure and the benefit is proportional to the degree of blood pressure-lowering. Thiazide diuretics are effective in lowering blood pressure and have been the most widely prescribed blood pressure-lowering drugs. They work by causing both sodium and water loss, but also cause potassium loss and a fall in plasma potassium levels. The latter may mitigate the beneficial effects from blood pressure-lowering. Some diuretics, such as spironolactone, affect the distal tubule and do not cause a fall in plasma potassium levels. However, spironolactone has endocrine side-effects associated with the fact that it is not specific for the mineralocorticoid receptor. The development of a more selective aldosterone antagonist without endocrine side-effects could be a major advance as it would be able to oppose the effects of aldosterone, both on sodium retention and potassium loss and the other vascular effects.