DIFFERENTIAL-EFFECTS OF FELODIPINE AND NIFEDIPINE ON 24-H BLOOD-PRESSURE AND LEFT-VENTRICULAR MASS

1,4-Dihydropyridine calcium antagonists, which have a rapid onset and short duration of action, tend to increase sympathetic activity, which may limit the regression of left ventricular hypertrophy when used fo r the treatment of hypertension. This study compares the effects of th e shorter-acting formulation of nifedipine (PA) with longer-acting fel odipine (ER) on 24-h blood pressure and left ventricular mass in patie nts with uncomplicated essential hypertension. Subjects were randomly allocated to receive nifedipine (n = 52) or felodipine (n = 56) over 8 weeks at increasing doses until the sitting office diastolic blood pr essure (DBP) was < 90 mm Hg. An ambulatory blood pressure (ABP) record ing and echocardiogram were performed at baseline and upon completion of the study. At the end of the dosing interval, felodipine lowered of fice DBP (mm Hg) by -18 +/- 12/14 +/- 1 compared to -14 +/- 2/11 +/- 1 for nifedipine (P less than or equal to .05). Mean 24-h ABP was reduc ed (P <.001) by felodipine (-15 +/- 1/-10 a 1 mm Hg) and nifedipine (- 15 +/- 1/-9 +/- 2 mm Hg). However, nifedipine caused an apparent bipha sic response with felodipine reducing (P <.05) blood pressure more in the early afternoon compared to nifedipine. Left ventricular mass inde x was significantly reduced (P <.01) by felodipine (-6 +/- 1 g/m(2)), but not by nifedipine. Once-daily administration of felodipine achieve s a more consistent control of blood pressure compared to twice-daily nifedipine and may be associated with a greater reduction in left vent ricular mass.