To compare a combination of a dihydropyridine calcium-channel blocker with an angiotensin converting enzyme inhibitor vs. monotherapy with one or the other drug and placebo for their effects on home blood pressure (HBP).
After a 2-week placebo wash-out, patients with an elevated office blood pressure (BP) (diastolic 100–109 and systolic <180 mmHg) and HBP (diastolic ≥85 mmHg) were randomized double-blind to a 10-week treatment with placebo, lercanidipine, 10 or 20 mg daily, enalapril, 10 or 20 mg daily, or the four possible combinations. In addition to office BP, HBP was self-measured via a validated semiautomatic device twice in the morning and twice in the evening during the 7 days before randomization and at the end of treatment. Baseline and treatment HBP values were separately averaged for each day, morning, evening or the whole monitoring period, excluding the first day. Day-by-day HBP variability was defined as the SD or the variation coefficient of the daily BP averages.
Eight hundred and fifty-four patients with valid HBP recordings at baseline and at the end of treatment were analyzed (intention-to-treat population). From the baseline value (147.0±11.6 mmHg) systolic/diastolic HBP showed a small reduction (average baseline-adjusted change: –1.8/–1.6 mmHg) with placebo, a more marked significant fall with monotherapies (−8.8/−5.9 mmHg, P < 0.001/<0.001 vs. placebo) and even more with combination treatment (11.6/−7.6 mmHg, P < 0.001/ < 0.001 vs. placebo and P < 0.01/ < 0.05 vs. monotherapy). A similar pattern was observed for each of the days of the BP self-monitoring period as well as for either morning or evening values, although the difference between mono and combination treatment appeared to be consistently significant for the morning values only. Day-by-day systolic BP-SD was unaffected by placebo and slightly reduced by drug treatments, with no, however, significant changes in SBP-variation coefficient. Baseline and end of treatment HBP values showed a limited correlation with office BP values, this being particularly the case for treatment-induced changes (correlation coefficients: 0.37 for systolic and 0.45 for diastolic BP).
This large HBP database shows that the lercanidipine–enalapril combination lowers HBP more effectively than the corresponding monotherapies and placebo, and that this greater effect is consistent between days.
ClinicalTrials.gov identifier: NCT01093807.