The DASH diet enhances the blood pressure response to losartan in hypertensive patients.

BACKGROUND The Dietary Approaches to Stop Hypertension (DASH) diet, which emphasizes fruits, vegetables, and low fat dairy products, significantly lowers blood pressure (BP). We conducted a clinical trial to assess the BP response to the DASH diet with an antihypertensive medication, losartan, in participants with essential hypertension. METHODS A total of 55 hypertensive participants were randomly assigned to 8 weeks of controlled feeding with either a control diet or the DASH diet. Within each diet arm, participants received losartan 50 mg daily or placebo for 4 weeks each, in double blind, randomized, cross-over fashion. Twenty-four-hour ambulatory BP (ABP) was measured at the end of a 2-week run-in period (baseline) and after each 4-week intervention period. RESULTS There was no significant change in ABP during the placebo period on the control diet (n = 28) (-2.3 +/- 1.5/-1.6 +/- 1.0 mm Hg), but there was a significant reduction in systolic ABP (-5.3 +/- 1.5 mm Hg, P <.05) and no change in DBP (-2.5 +/- 1.0 mm Hg) on the DASH diet (n = 27). Losartan significantly reduced ABP on the control diet (-6.7 +/- 1.5/-3.7 +/- 1.0 mm Hg, P <.05) and to a greater extent on the DASH diet (-11.7 +/- 1.5/-6.9 +/- 1.0 mm Hg, P <.05 versus basal and control diet) particularly in African Americans. On the DASH diet, DeltaSBP on losartan was inversely related to basal plasma renin activity (n = -0.53, P =.004). CONCLUSIONS The DASH diet enhances the ABP response to losartan in essential hypertension. This effect is particularly marked in African Americans.