Degree of concordance with DASH diet guidelines and incidence of hypertension and fatal cardiovascular disease

Background: Guidelines to prevent and treat hypertension advocate the Dietary Approaches to Stop Hypertension (DASH) diet. Methods: We studied whether a greater concordance with the DASH diet is associated with reduced incidence of hypertension (self-reported) and mortality from cardiovascular disease in 20,993 women initially aged 55 to 69 years. We created a DASH diet concordance score using food frequency data in 1986 and followed the women for events through 2002. Results: No woman had perfect concordance with the DASH diet. Adjusted for age and energy intake, incidence of hypertension was inversely associated with the degree of concordance with the DASH diet, with hazard ratios across quintiles of 1.0, 0.91, 0.95, 0.99, and 0.87 (P trend =.02). There also were inverse, but not monotonic, associations between better DASH diet concordance and mortality from coronary heart disease, stroke, and all cardiovascular disease (CVD). However, after adjustment for other risk factors, there was little evidence that any end point was associated with the DASH diet score. Conclusions: Our results suggest that greater concordance with DASH guidelines did not have an independent long-term association with hypertension or cardiovascular mortality in this cohort. This implies that very high concordance, as achieved in the DASH trials, may be necessary to achieve any benefits of the DASH diet.