Antihypertensive and Metabolic Effects of Angiotensin Receptor Blocker/Diuretic Combination Therapy in Obese, Hypertensive African American and White Patients

Abstract

A clinical trial showed comparable blood pressure (BP) lowering by valsartan/hydrochlorothiazide and amlodipine/hydrochlorothiazide in obese hypertensive patients. Relative to amlodipine/hydrochlorothiazide, valsartan/hydrochlorothiazide reduced the hyperglycemic response to glucose challenge. An objective of this post hoc analysis was to determine whether this benefit extended to African Americans and whites. Treatments (160/12.5 mg of valsartan/hydrochlorothiazide force titrated to 320/25 mg of valsartan/hydrochlorothiazide at week 4 or 12.5 mg of hydrochlorothiazide force titrated to 25 mg of hydrochlorothiazide at week 4 with 5 and 10 mg of amlodipine added at weeks 8 and 12, respectively) were administered once daily. Both treatments reduced clinic BP from baseline to all visits (P < 0.0001), regardless of race/ethnicity (126 African Americans, 212 whites). In African Americans, there were no significant between-treatment differences in clinic or ambulatory BP lowering at weeks 8 or 16. Whites responded better to valsartan/hydrochlorothiazide. In both racial/ethnic subgroups, the addition of valsartan but not amlodipine mitigated the hyperglycemic response to hydrochlorothiazide through enhanced insulin secretion. Valsartan/hydrochlorothiazide was as effective as amlodipine/hydrochlorothiazide was in reducing BP in obese, hypertensive African Americans and better than amlodipine/hydrochlorothiazide in whites. In both racial/ethnic subgroups, the addition of valsartan to hydrochlorothiazide reduced the negative metabolic effects associated with thiazide therapy.