Background: In the treatment of hypertension in subjects of African origins, although hydrochlorothiazide (HCTZ) is not as effective as calcium channel blockers, indapamide is superior to HCTZ. In the present study we therefore compared the effects of slow release (SR) indapamide with the calcium channel blocker amlodipine, when used as initial therapy, on blood pressure (BP) and left ventricular mass (LVM) during 6 months of treatment in this group.
Methods: Patients with a mean daytime ambulatory diastolic BP > or =90 mm Hg and < or =110 mm Hg (n = 125, aged 53 +/- 11 years, 68% women) were randomized to receive open-label 1.5 mg of indapamide SR or 5 mg of amlodipine. If daytime ambulatory diastolic BP at 1 month was >/=90 mm Hg, 4 mg of perindopril was added to indapamide SR or the dose of amlodipine was increased to 10 mg.
Results: After 1 month of therapy, there was an equivalent decline in systolic and diastolic BP in both groups (P <.0001). In the indapamide-treated group (n = 62) the daytime BP decreased from 153 +/- 12/101 +/- 6 mm Hg to 138 +/- 15/92 +/- 10 mm Hg and for amlodipine (n = 58), it decreased from 152 +/- 13/99 +/- 5 mm Hg to 138 +/- 12/91 +/- 8 mm Hg. At 6 months daytime ambulatory BP decreased to 130 +/- 15/86 +/- 8 mm Hg and to 129 +/- 11/85 +/- 5 mm Hg for the indapamide SR (n = 42) and amlodipine (n = 44) treatment groups, respectively. Both groups showed equivalent regression of LVM index and relative wall thickness.
Conclusions: These data suggest that in hypertensive patients of African ancestry initiating therapy with 1.5 mg of indapamide SR and then adding 4 mg of perindopril is equally as effective as amlodipine therapy at reducing BP, and modifying target organ damage.