Comparison of indapamide and low-dose hydrochlorothiazide monotherapy in black patients with mild to moderate hypertension
Radevski, I.V.; Valtchanova, Z.P.; Candy, G.P.; Wald, A.M.; Ngcezula, T.; Sareli, P.
South African Medical Journal 92(7): 532-536
2002
ISSN/ISBN: 0256-9574 PMID: 12197195 Document Number: 549882
Objectives: To assess, using ambulatory blood pressure monitoring (ABPM), the antihypertensive efficacy of hydrochlorothiazide 12.5 mg and indapamide 2.5 mg given as a monotherapy over 3 months to black patients with mild to moderate essential hypertension. Design: Single-centre, prospective, randomised open pilot study in three phases: (i) 1-week drug-free washout period; (ii) 2-week placebo run-in phase; and (iii) 3-month prospective open-label active treatment period. Results: Forty-two black patients with mean daytime diastolic BP (DBP) gtoreq90 mmHg and ltoreq115 mmHg (mean age 57+-11 years, 28 women/14 men) were enrolled into the study. Overall, a profound and sustained BP reduction was achieved with indapamide at 3 months (N=20). The 24-hour BP decreased from 150+-17/94+-6 mmHg to 130+-19/82+-9 mmHg (P<0.0001 for systolic BP (SBP) and DBP at 3 months versus baseline); the mean daytime BP decreased from 155+-15/98+-6 mmHg to 134+-18/87+-10 mmHg (P<0.0001 for SBP and DBP at 3 months versus baseline). The overall control (mean daytime DBP <90 mmHg) and response (decrease in daytime DBPgtoreq10 mmHg) rates achieved with indapamide were 10/20 (50%) and 13/20 (65%), respectively. In contrast, monotherapy with hydrochlorothiazide resulted in more modest BP reduction and control and response rates at 3 months (N=22). The 24-hour BP decreased from 147+-14/94+-7 mmHg to 139+-19/88+-2 mmHg (P<0.05 for DBP at 3 months versus baseline, P=NS for SBP); the mean daytime BP decreased from 151+-14/98+-5 mmHg to 144+-16/93+-10 mmHg (P<0.05 for DBP at 3 months versus baseline, P=NS for SBP). The corresponding control and response rates were 7/22 (32%) and 8/22 (36%). Both hydrochlorothiazide and indapamide caused significant hypokalaemia. Conclusions: Monotherapy with indapamide is associated with greater BP reduction and control and response rates than monotherapy with low-dose hydrochlorothiazide and may be an appropriate choice of antihypertensive diuretic therapy in black South African patients with mild to moderate hypertension.