Health outcomes associated with calcium antagonists compared with other first-line antihypertensive therapies: a meta-analysis of randomised controlled trials.

BACKGROUND Several observational studies and individual randomised trials in hypertension have suggested that, compared with other drugs, calcium antagonists may be associated with a higher risk of coronary events, despite similar blood-pressure control. The aim of this meta-analysis was to compare the effects of calcium antagonists and other antihypertensive drugs on major cardiovascular events. METHODS We undertook a meta-analysis of trials in hypertension that assessed cardiovascular events and included at least 100 patients, who were randomly assigned intermediate-acting or long-acting calcium antagonists or other antihypertensive drugs and who were followed up for at least 2 years. FINDINGS The nine eligible trials included 27,743 participants. Calcium antagonists and other drugs achieved similar control of both systolic and diastolic blood pressure. Compared with patients assigned diuretics, beta-blockers, angiotensin-converting-enzyme inhibitors, or clonidine (n=15,044), those assigned calcium antagonists (n=12,699) had a significantly higher risk of acute myocardial infarction (odds ratio 1.26 [95% CI 1.11-1.43], p=0.0003), congestive heart failure (1.25 [1.07-1.46], p=0.005), and major cardiovascular events (1.10 [1.02-1.18], p=0.018). The treatment differences were within the play of chance for the outcomes of stroke (0.90 [0.80-1.02], p=0.10) and all-cause mortality (1.03 [0.94-1.13], p=0.54). INTERPRETATION In randomised controlled trials, the large available database suggests that calcium antagonists are inferior to other types of antihypertensive drugs as first-line agents in reducing the risks of several major complications of hypertension. On the basis of these data, the longer-acting calcium antagonists cannot be recommended as first-line therapy for hypertension.