Effect of Hypotensive Drugs on the Circadian Blood Pressure Pattern in Essential Hypertension: a Comparative Study

To compare the effect of four drug groups on the ambulatorycircadian blood pressure (BP) pattern, amiloride hydrochlorothiazide,atenolol, nifedipine, and perindopril (5/50 mg/d, 100 mg/d, 40mg/d, and 4 mg/d respectively, for 14 days) were alternated in eachof 20 essential hypertension patients. Diuretics induced the largest (P<0.05) drop in mean 24-hour systolic BP (–12 mmHg, P < 0.001).Atenolol reduced only its standard deviation, and nifedipine reduced onlythe mean daytime systolic BP (P < 0.05). The mean 24-hour diastolic BPwas equally reduced by all drugs except nifedipine, which only reduced (P< 0.05) the mean daytime value. The mean 24-hour heart rate wasdecreased by atenolol (P < 0.001), increased by diuretics (P <0.05), and unchanged with perindopril, while nifedipine increased (P < 0.05) only its night-time value. In conclusion, diuretics were the strongest agents in reducing systolic BP, atenolol the only agent thatreduced variability, perindopril the only agent that did not affect theheart rate, and nifedipine reduced only daytime BP values.