Objective: The blood pressure (BP)-lowering response to renin-angiotensin-aldosterone system blockade in hypertensive African-Americans is typically less than in whites. To determine whether higher than conventional doses of renin-angiotensin-aldosterone system blockade can improve BP reduction in African-American patients.
Methods: Hypertensive patients with type 2 diabetes and albuminuria were enrolled: 110 African-Americans (BP = 150/87 mmHg, aged 57.5 +/- 11 years) and 281 non-African-Americans (BP = 151/89 mmHg, aged 57.7 +/- 11 years). All patients received valsartan 160 mg once daily in the morning for 4 weeks, following which patients were randomized to receive one of three valsartan doses: 160, 320 or 640 mg/day (2x, maximal recommended dose) for 26 weeks. If at week 6, target BP (<130/80 mmHg) was not achieved, then other add-on antihypertensives were allowed.
Results: The predominant BP (DeltaSBP/DeltaDBP) reduction was observed within 4 weeks and was lesser in African-Americans (7.8 +/- 15/4.5 +/- 9 mmHg) than non-African-Americans (8.9 +/- 14/6.6 +/- 1 mmHg, P < 0.05). Greater reduction in urinary albumin excretion was observed with higher doses (320 or 640 mg); however, the responses were similar between African-Americans and non-African-Americans. Use of add-on antihypertensives was higher in African-American (56%) vs. non-African-American patients (36%) with a similar rate across the three valsartan doses. From week 4-26, reduction in BP was lesser (P < 0.05) for African-American than non-African-American patients at the160-mg dose but not with 320 and 640-mg doses.
Conclusion: In African-American patients, a lower BP reduction response was observed to conventional doses of valsartan than non-African-American patients, but at 640 mg, a higher response was observed in African-American patients than in non-African-American patients.
Trial registration: ClinicalTrials.gov NCT00241085.