Calcium-channel blockade and cardiovascular prognosis: recent evidence from clinical outcome trials

This article has three purposes: 1) to summarize recent findings of the Syst-Eur Trial; 2) to provide a short overview of the large trials in hypertension that have compared older with newer drug classes; and 3) to update the results of a meta-regression analysis that addressed the question of: to what extent blood pressure (BP) lowering can explain the findings of recent outcome trials in hypertensive patients or high-risk patients with normotension or hypertension. The Syst-Eur trial showed that in older patients with isolated systolic hypertension, drug treatment starting with a dihydropyridine calcium channel blocker reduced the risk of stroke and of all cardiovascular complications. Furthermore, this treatment regimen improved the prognosis of diabetic patients; reduced the incidence of proteinuria; and prevented dementia, in particular Alzheimer’s disease. The pooled evidence from nine recently published actively controlled outcome trials involving 62,605 hypertensive patients proved that calcium channel blockers have the same long-term efficacy and safety as the older drug classes. Compared with diuretics and β-blockers, calcium channel blockers may offer greater protection against stroke and less protection against myocardial infarction, resulting in similar overall cardiovascular benefit. A meta-regression analysis including 30 trials and 149,407 hypertensive or high-risk patients showed that BP gradients largely accounted for most—if not all—of the differences in outcome. These findings emphasize the desirability of tight BP control. The hypothesis that angiotensin converting enzyme inhibitors or α-blockers might influence outcome beyond their BP lowering-effects was not confirmed.