[Calcium antagonists in the therapy of arterial hypertension in the aged]

Abstract

A large number of epidemiologic and interventional studies go to show that acute cerebral and cardiac events and chronic organ injury are significantly less frequent in treated compared to untreated elderly hypertensives. These observations clearly show that hypertension in the elderly must be treated. As to water-electrolyte metabolism, activity of the renin-angiotensin-aldosterone axis as well as volemia are reduced in the elderly while extravascular liquid compartment and activity of the natriuretic atrial factor are both increased. In addition, there is reduction of the baroceptor reflexes accompanied by vasoconstriction and hypertrophy of the smooth muscles associated with increased intracellular calcium ion content. These pathophysiologic conditions appear to supply the rationale for the preference accorded to calcium channel blockers compared to other drugs usually employed in the management of younger hypertensives. Moreover, second generation dihydropyridines, thanks to their liposolubility and ties with calcium channel subunits, show rapid onset and long action that allows for a single daily dose and lowers the incidence of side effects. A large number of interventional trials employing calcium channel blockers have demonstrated the efficacy of these drugs for reducing arterial hypertension. However, these trials concern young hypertensives whereas there is a lack of similar studies in elderly subjects, were clinical trials are few and involve limited numbers of subjects. Results of multicentre studies, at present in progress, will permit to assess the efficacy and incidence of side effects of second generation calcium channel blockers in hypertension of the elderly.