High-dose monotherapy vs low-dose combination therapy of calcium channel blockers and angiotensin receptor blockers in mild to moderate hypertension

The objectives of the study were to compare long- acting dihydropyridine calcium channel blockers ( CCBs) with angiotensin II receptor blockers ( ARBs) according to the ambulatory blood pressure monitoring ( ABPM) profile in stage 1 and 2 newly diagnosed hypertensives and also to evaluate the efficacy of high- dose monotherapy vs low- dose combination therapy of the two drug categories among the subjects with inadequate blood pressure ( BP) control after conventional low- dose monotherapy. We obtained 24- h ABPM readings from 302 subjects with newly diagnosed stage 1 or 2 essential hypertension. The study protocol consisted of initial drug treatment with a low dose of either CCBs or ARBs. Hypertensives who did not achieve BP control were randomized to high- dose monotherapy of either category of drug or low- dose combination therapy. CCBs and ARBs in low- dose monotherapy achieved BP control in 53.8 and 55.3% of the cases, respectively. However, subjects under treatment with CCBs experienced side effects more often and required that treatment be discontinued. Hypertensives who failed to control their BP with low- dose monotherapy did significantly better with low- dose combination treatment ( 61.6%) than with high- dose CCBs ( 42.8%) or ARBs ( 40.5%) monotherapy ( P < 0.05). In terms of ABPM, low-dose combination therapy exhibited better 24- h BP profile according to trough- to- peak ratio, hypertensive burden and BP variability. In conclusion, low- dose ARBs and CCBs have a comparable effect in subjects with grade 1 and 2 arterial hypertension. In hypertensives who are not controlled by low- dose monotherapy, low-dose combination therapy proves be more efficacious than high- dose monotherapy.