L. Vaur et al., DIFFERENTIAL-EFFECTS OF A MISSED DOSE OF TRANDOLAPRIL AND ENALAPRIL ON BLOOD-PRESSURE CONTROL IN HYPERTENSIVE PATIENTS, Journal of cardiovascular pharmacology, 26(1), 1995, pp. 127-131
A double blind randomised comparison of two angiotensin-converting enz
yme (ACE) inhibitors was made in a study in which ambulatory blood pre
ssure was monitored over a steady-state dosage interval and the subseq
uent 24-h period, the latter being designed to mimic a missed dose of
drug. The blood pressure responses on active therapy were compared to
an identical recording made at the end of a 3-week placebo run in peri
od. Eighty-eight essential hypertensives were treated with a morning d
ose of either trandolapril 2 mg or enalapril 20 mg. Mean systolic (SEP
) and diastolic blood pressure (DBP) were calculated on each of the fo
llowing periods: daytime (8:31 a.m.-10:30 p.m.), nighttime (10:31 p.m.
-6:30 a.m.), and early morning (6:31 a.m.-8:30 a.m.). Trough/peak was
calculated for each group both on active treatment and after a missed
dose. Twelve patients were excluded from analysis before opening the r
andomisation code because of inadequate ambulatory blood pressure moni
toring (ABPM) recordings. Demographic data, placebo-period office bloo
d pressure, and ABPM recordings were not significantly different betwe
en the two groups. Both trandolapril and enalapril effectively reduced
blood pressure over the 24-h period. Twenty four-hour ambulatory SEP
and DBP decreased from 148 +/- 14/92 +/- 10 mm Hg to 135 +/- 14/83 +/-
10 mm Hg in the trandolapril group (p < 0.001). The same parameters d
ecreased to a quite similar extent after enalapril, from 143 +/- 13/91
+/- 5 mm Hg to 133 +/- 15/83 +/- 8 mm Hg (p < 0.001). The trough/peak
ratio on active treatment was 90% (SBP) and 54% (DBP) in the trandola
pril group and 49% (SBP and DBP) in the enalapril group. Following the
missed dose, trough/peak ratio decreased to 58% (SBP)/36% (DBP) for t
randolapril and 10% (SBP)/19% (DBP) for enalapril. The blood pressure
control was better sustained with trandolapril, such that significant
falls in blood pressure were observed during the daytime, nighttime an
d early morning periods after a missed dose, whereas during the same p
eriods, enalapril only significantly reduced blood pressure in the day
time period.