NITRENDIPINE 20 MG ONCE DAILY VERSUS NICARDIPINE SLOW RELEASE 40 MG TWICE DAILY IN MILD ESSENTIAL-HYPERTENSION - EVALUATION BY 24-HOUR AMBULATORY BLOOD-PRESSURE MONITORING

The extent and duration of the blood pressure (BP) lowering effect of 20 mg nitrendipine (NIT) once daily and 40 mg nicardipine slow release (NIC) twice daily were compared in 12 men (aged 39-55 years) with mild essential hypertension according to a randomized, cross over study. Twenty-four-hour non invasive ambulatory BP monitoring (Spacelabs 5200) was performed at the end of a 2-week placebo run-in and after 4 weeks of each active treatment; automatic BP measurements were programmed at 15-min intervals. Both treatments significantly (p<.01) reduced mean 24-hour and daytime systolic (SBP) and diastolic (DBP) BP, but had different effects on daytime BP profiles. NIT decreased SBP and DBP (p<.05) in 5 out of 8 two-hour subperiods (from 8 a.m. to 6 p.m.), followed by a loss of effect; NIC reduced SBP and DBP (p<.05) in 7 out,of 8 two-hour subperiods (from 8 a.m. to 10 p.m.). During the night-time, NIT reduced mean SBP (p<.05) and NIC both mean SBP and DBP values (p<.05; p <.05 vs NIT for SBP). Heart rate was not affected by either treatment. Thus, after short-term treatment in mild essential hypertensives nitrendipine once daily was not as effective as nicardipine slow release twice daily in reducing blood pressure throughout the 24 hours.