Fourteen studies (n=23,751) were included in the review, nine of which involved a calcium antagonist. Four studies were placebo-controlled (n=2,321), two of which were of calcium antagonists.
Compared with placebo, one trial of calcium antagonists generated a statistically significant reduction in the odds of any cardiovascular outcome (OR 0.37, 95% CI: 0.18, 0.93), stroke (OR 0.27, 95% CI: 0.12, 0.76) and total mortality (OR 0.45, 95% CI: 0.28, 0.91). However, the results from the other trial showed no statistically significant difference for any of these outcomes. The data were not pooled across these trials.
Trials that compared calcium antagonists with either beta-blockers or diuretics (4 trials, n=11,773) found that there was no statistically significant differences for pooled results for odds of CHD, stroke, heart failure or total mortality. The only statistically significant finding was that for CHD when amlodipine was compared with diuretics or beta-blockers (OR 0.58, 95% CI: 0.37, 0.92).
Trials that compared calcium antagonists with ACE inhibitors or ARBs (4 trials, n=2,462) found that there were no statistically significant differences for pooled results for odds of MI, stroke, heart failure or total mortality. Two trials found a statistically significant increased risk of MI with the calcium antagonist compared with an ACE inhibitor (nisoldipine versus enalapril OR 5.5, 95% CI: 2.10, 14.6; felodipine/isradipine versus enalapril/captopril OR 1.96, 95% CI: 1.09, 3.57).