The aim of the present study was to compare the cardiovascular effects of olmesartan, an angiotensin II receptor blocker, combined with a calcium channel blocker (CCB) or a diuretic, in a prospective, randomized, open-label, blinded endpoint trial.
Japanese hypertensive patients aged at least 65 to less than 85 years with SBP at least 140 mmHg and/or DBP at least 90 mmHg with antihypertensive treatment, or SBP at least 160 mmHg and/or DBP at least 100 mmHg without antihypertensive treatment were randomized to receive olmesartan with either a dihydropyridine CCB or a low-dose diuretic. If SBP and/or DBP remained at least 140 and/or at least 90 mmHg, the other antihypertensive drug was added. The primary endpoint was a composite of fatal and nonfatal cardiovascular events. The median follow-up time was 3.3 years.
Blood pressure decreased similarly in both groups. The primary endpoint occurred in 116/2568 patients (4.5%) in the olmesartan plus CCB group and in 135/2573 patients (5.3%) in the olmesartan plus diuretic group [hazard ratio 0.83, 95% confidence interval (CI) 0.65–1.07, P = 0.16]. Rates of all-cause death and cardiovascular deaths were similar. Among patients aged at least 75 years, the incidence of stroke tended to be lower in the olmesartan plus CCB group than in the olmesartan plus diuretic group (hazard ratio 0.63, 95% CI 0.38–1.02, P = 0.059, interaction P = 0.019). Fewer patients in the olmesartan plus CCB group (8.2%, 211/2568) than in the olmesartan plus diuretic group (9.8%, 253/2573; P = 0.046) experienced serious adverse events.
Despite no significant difference in cardiovascular events, the different safety profiles suggest that the combination of olmesartan and CCB may be preferable to that of olmesartan and diuretic.