Risk-benefit aspects of antihypertensive drugs.

Several long term trials using traditional antihypertensive therapy with diuretics and beta-blockers have shown that antihypertensive therapy reduces the overall risk of cardiovascular complications. However, even after several years of therapy the cardiovascular risk in hypertensive patients cannot be lowered to that in the normotensive population. Antihypertensive therapy can reduce the incidence of cerebrovascular complications in patients with hypertension by about 65%. However, the effect of such therapy in preventing coronary events has been disappointing, as these events are 3 to 4 times more common than cerebrovascular complications in hypertensive patients. It is now apparent that adverse pharmacological effects of diuretics and beta-blockers on lipid metabolism persist for many years. Thus, treatment with these agents constitutes a new risk factor for coronary heart disease and may, at least in part, explain the failure of traditional antihypertensive therapy to reduce the incidence of myocardial infarction and sudden death as effectively as that of cerebrovascular accidents. On the other hand, titration of these antihypertensive agents to the lowest possible dose in order to avoid metabolic alterations and subjective adverse effects has frequently resulted in the administration of subtherapeutic doses, particularly for hydrochlorothiazide. Until comparative long term clinical trials with older and newer antihypertensive agents and morbidity and mortality as end-points are completed, the debate on first-line drugs for antihypertensive treatment will not be satisfactorily resolved.