ONCE-DAILY PERINDOPRIL VERSUS SLOW-RELEASE DILTIAZEM IN THE TREATMENT OF MILD-TO-MODERATE ESSENTIAL-HYPERTENSION

The efficacy and acceptability of the angiotensin-converting enzyme (ACE) inhibitor perindopril were compared with those of an established treatment for hypertension in Canada, slow release diltiazem. Hypertensive patients aged 18 to 64 years presenting a mean sitting diastolic blood pressure (DBP) between 95 and 110 mmHg inclusive were randomized if they were without any concurrent serious renal, hepatic, cardiac or psychiatric illnesses. A total of 49 of 83 patients qualified for randomization after four weeks on placebo, 23 were assigned to the perindopril treatment group and 26 to the diltiazem treatment group. Starting doses (4 mg od in the perindopril group and 120 mg [60 mg bid] in the diltiazem group) were increased to a maximum of 8 mg od in the perindopril group and to 360 mg (180 mg bid) in the diltiazem group if DBF remained above 90 mmHg. Hydrochlorothiazide was added at week 8 if goal blood pressure was not achieved with the maximum dose. Both groups were comparable at randomization; baseline systolic blood pressure (SGP)/DBP were 153/100 mmHg and 150/99 mmHg in the perindopril and diltiazem groups, respectively. A significant decrease in SBP/DBP was observed from the second week of treatment: -10/-8 mmHg in the perindopril group and -8/-8 mmHg in the diltiazem group. This fall in blood pressure was maintained throughout the duration of the trial: -13/-9 and -13/-11 mmHg for the perindopril and diltiazem groups, respectively, at week 12, at which time monotherapy was taken by over 80% of patients and compliance was consistently over 90%. One patient treated with perindopril withdrew before the end of the trial due to depression associated with personal problems. Systematic questioning about an exhaustive list of 11 symptoms at all visits showed no significant trends and no serious events. There were no significant changes in any laboratory parameters. Both drugs had a neutral effect on serum lipids, glucose, serum markers of kidney and renal function and on hematological parameters. In conclusion, this Canadian multicentre trial confirmed that the efficacy and acceptability of the once daily ACE inhibitor perindopril, administered in a simple dosing scheme of 4 to 8 mg, is equivalent to that of slow release diltiazem in the treatment of hypertension.