Background: Dihydropyridine calcium channel blockers are a heterogeneous group of antihypertensive drugs. Long-acting dihydropyridine agent amlodipine is widely used for monotherapy and combination therapy for hypertension in clinical practice, while intermediate-acting dihydropyridine agents have shown inconsistent results in randomized clinical trials (RCTs).
Methods and results: A meta-analysis of 18 RCTs enrolling a total of 80,483 patients with hypertension followed for a mean of 51.4 months was performed. Amlodipine therapy was associated with 25% higher risk of heart failure (relative risk [RR]: 1.25, 95% confidence interval [CI], 1.05-1.49, P = .019) but 17% lower risk of stroke (RR: 0.83, [95% CI, 0.72-0.97], P = .009) without statistically significant effect on acute myocardial infarction (AMI) compared to major alternative antihypertensive therapy (MAAT), including β-blocker, diuretic, angiotensin-converting enzyme inhibitor, or angiotensin-receptor blocker. Intermediate-acting dihydropyridine calcium channel blocker therapy was associated with 25% higher risk of heart failure (RR: 1.25, [95% CI, 1.06-1.47], 0.005, P = .005) and 26% higher risk of AMI (RR: 1.26, [95% CI, 1.05-1.51], 0.019, P = .019) compared to MAAT. Results of the subgroup analysis suggested that the intermediate-acting dihydropyridine calcium channel blocker was associated with higher risk of heart failure (RR: 1.30, [95% CI, 1.08-1.56], P = .005) and AMI (RR: 1.50, [95% CI, 1.01-2.22], P = .043) compared to renin-angiotensin system blockers and a trend toward higher risk of AMI (RR: 1.17, [95% CI, 0.99-1.38], P = .064) compared to conventional therapy, including β-blockers and diuretics. Meta-regression analyses suggested that long-acting dihydropyridine calcium channel blocker is associated with lower risk of AMI ( B: -0.327, [95% CI, -0.530 to -0.123], P = .002) with a trend toward lower risk of stroke ( B: -0.203, [95% CI, -0.410 to 0.003] P = .054).
Conclusions: This study suggests that Amlodipine offers greater protection against major complications of hypertension compared to intermediate-acting dihydropyridine calcium channel blockers.
Keywords: acute myocardial infarction; calcium channel blockers; dihydropyridine; heart failure; hypertension; stroke.