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

Summary 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, β-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% Cl 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.