SLOW-RELEASE ORAL ISRADIPINE IN THE TREATMENT OF ESSENTIAL-HYPERTENSION

The antihypertensive efficacy of slow-release oral (SRO) isradipine wa s evaluated in 392 patients (mean age, 53 +/- 9 years) with mild-to-mo derate essential hypertension (diastolic blood pressure [DBP] 96 to 11 0 mm Hg). Patients from 15 hospitals throughout Italy participated in this 26-week study. After a 2-week placebo run-in period, patients wer e treated with 5 mg/d of isradipine; 6 weeks later, 10 to 20 mg of ena lapril was added if DBP was not adequately reduced. At baseline and af ter 6 and 26 weeks of treatment, ambulatory 24-hour blood pressure (BP ) recordings were made with measurements every 15 minutes during wakin g hours (7 AM to 11 PM) and every 30 minutes during nighttime (11 PM t o 7 AM). Seated office BP was significantly reduced by isradipine alon e and in combination with enalapril: mean overall group casual BP meas urements fell by 15 mm Hg (systolic blood pressure [SBP]) and 10 mm Hg (DBP) at 6 weeks and 22 mm Hg (SBP) and 16 mm Hg (DBP) at 26 weeks co mpared with baseline. There was no significant difference between the two regimens. Mean 24-hour ambulatory BP of all 392 patients was lower with isradipine treatment at weeks 6 and 26, without changes in 24-ho ur BP profiles. The most frequent side effects observed were headache, flushing, ankle edema, and palpitations. These were responsible for a 4.8% dropout rate. No clinically important variations were observed i n blood chemistries. The results of this large-scale study confirm tha t 5 mg/d of isradipine SRO is effective and well tolerated in the trea tment of patients with mild-to-moderate essential hypertension. Analys is of BP profiles showed that, despite the marked antihypertensive eff ect persisting over 21 hours, the physiologic circadian BP rhythm was maintained.