Ambulatory blood pressure profiles in essential hypertensives after treatment with a new once daily nifedipine formulation
The antihypertensive efficacy of a new controlled-release preparation of nifedipine developed for once daily administration was investigated in comparison with a standard therapy with sustained-release nifedipine given twice daily in a randomised, open crossover trial. Twenty-two patients with mild to moderate essential hypertension were enrolled. Ambulatory blood pressure monitoring (ABPM) was performed after a wash-out period and after a 3 weeks treatment with 40 mg controlled-release nifedipine once daily and 20 mg sustained-release nifedipine twice daily, respectively. ABPM data were evaluated by conventional linear analysis and by rhythm analysis. Both once daily and twice daily administration of nifedipine significantly reduced systolic blood pressure during the daytime and during the night when compared with baseline. The 24-h diastolic blood pressure was significantly decreased by both treatments, but only the once daily regimen significantly lowered both diastolic daytime and night-time means. Comparing systolic and diastolic blood pressures after both treatments, however, no significant differences were obtained. Both nifedipine treatments did neither greatly modify the circadian blood pressure pattern nor reflexly increase heart rate. In conclusion, once daily application of the controlled-release formulation of nifedipine resulted in a consistent and significant blood pressure reduction. Once daily and twice daily medications of nifedipine were about equally effective in lowering the elevated blood pressures.