Association Between a DASH-Like Diet and Mortality in Adults With Hypertension: Findings From a Population-Based Follow-Up Study

BACKGROUND: Although the Dietary Approaches to Stop Hypertension (DASH) diet lowers blood pressure (BP) in hypertensive adults, its effect on mortality is unclear. METHODS: This prospective cohort study evaluated the association between diet and mortality in 5,532 hypertensive adults in the Third National Health and Nutrition Examination Survey. Hypertension was determined by self-report, medication use, or BP measurement. Diet was ascertained by 24-h dietary recall using nine nutrient targets. The primary outcome was all-cause mortality. Secondary outcomes included specific causes of mortality (cardiovascular disease (CVD), ischemic heart disease (IHD), stroke, and cancer). RESULTS: Of the 5,532 participants, 391 (7.1%) consumed a DASH-like diet. During an average of 8.2 person-years of follow-up, there were 1,537 all-cause deaths; this included 312 cancer deaths and 788 cardiovascular deaths, of which 447 were due to IHD and 142 were due to stroke. After adjusting for multiple confounders while accounting for the complex survey design by utilizing survey weights, strata, and clusters in Cox proportional hazards models, a DASH-like diet was associated with lower mortality from all causes (hazard ratio (HR) 0.69, 95% confidence interval (CI) 0.52-0.92, P = 0.01) and stroke (HR 0.11, 95% CI 0.03-0.47, P = 0.003). Mortality risk from CVD (HR 0.92, 95% CI 0.63-1.35, P = 0.67), IHD (HR 0.77, 95% CI 0.47-1.24, P = 0.28), and cancer (HR 0.51, 95% CI 0.23-1.10, P = 0.09) did not reach statistical significance. CONCLUSIONS: Though findings for specific causes of mortality are mixed, consumption of a DASH-like diet is associated with lower all-cause mortality in adults with hypertension.