3-PERIOD CROSSOVER TRIAL WITH AMBULATORY BLOOD-PRESSURE MONITORING FOR EVALUATING ANTIHYPERTENSIVE THERAPY

A double-blind, three-period, crossover trial used 24-hour ambulatory blood pressure monitoring to compare diltiazem controlled diffusion (C D) 300 mg with placebo. Patients with hypertension (N = 43) were rando mly assigned to one of four crossover treatment sequences of three tre atment periods each. Ambulatory blood pressure was obtained at the end of each 4-week treatment period. Diltiazem CD significantly decreased diastolic and systolic blood pressure at bihourly ambulatory blood pr essure evaluations (p < 0.05, all). However, when all ambulatory blood pressure monitoring data were combined into one statistical model, bl ood pressure reductions were quantifiably similar to those in the over all bihourly analysis, but with a consistent 24-hour antihypertensive effect for both diastolic and systolic blood pressure relative to that with placebo (i.e., parallel blood pressure profiles) and with increa sed precision. Mean +/- SE changes in diastolic and systolic blood pre ssure across the 24-hour dosing interval were -5.6 +/- 0.4 mm Hg and - 7.6 +/- 0.5 mm Hg, respectively (p < 0.001, both). Therefore, by using a crossover design with ambulatory blood pressure monitoring, we show ed diltiazem CD to reduce blood pressure consistently throughout a 24- hour dosing interval in comparison with placebo in patients with hyper tension.