Associations between change in DASH diet scores and CVD risk factors in the PREMIER Trial (369.1)

Abstract

OBJECTIVE: To measure associations between changes in the Dietary Approaches to Stop Hypertension (DASH) dietary indices and changes in blood pressure (BP), weight, and waist circumference (CVD risk factors) in PREMIER, a randomized, controlled trial of behavioral intervention for hypertension with and without the DASH dietary pattern.METHODS: DASH diet scores were derived based upon nutrient (9 nutrients, DASH_Nutrient) and food‐based (8 food groups, DASH_Food) targets using two 24‐h recalls administered at baseline, 6 months, and 18 months. Generalized estimating equations (GEE) were used to assess associations between CVD risk factors per SD change in the two DASH indices after accounting for confounders and randomization group.RESULTS: At baseline (n=807), lower DASH scores were associated with higher BMI, African‐American race, and younger age for both indices. Spearman correlations between the indices were 0.36. Mean DASH scores at baseline and 18 months were 2.7 (SD=1.4) and 3.7 (SD 1.4) for DASH_Nutrient (range 0 to 9) and 36.2 (SD=10.5) and 40.0 (SD 11.8) for DASH_Food (range 0‐80). Each SD increase in DASH_Nutrient was associated with a ‐1.26 (95% CI: ‐1.91 to ‐0.61) mmHg decrease in systolic BP versus a ‐0.87 (95% CI: ‐1.44 to ‐0.30) mmHg per SD change in DASH_Food. Each SD increase in DASH_Nutrient score was associated with a ‐0.50 (‐0.95 to ‐0.06) unit decrease in diastolic BP. Changes in the DASH_Food score were not significantly associated with changes in diastolic BP.INTERPRETATION: The DASH dietary pattern defined by nutrient, rather than food, intake is more closely associated with reduction in CVD risk factors.Table. Longitudinal associations (Mean (95% CI)) between changes from baseline in DASH Diet Scores and CVD risk factors CVD Risk Factor DASH_Nutrient (derived based on Mellen’s DASH Index), per SD DASH_Food (derived based on Gunther’s DASH Index), per SD Systolic Blood Pressure, mmHg ‐1.26 (‐1.91 to ‐0.61) ‐0.87 (‐1.44 to ‐0.30) Diastolic Blood Pressure, mmHg ‐0.50 (‐0.95 to ‐0.06) ‐0.32 (‐0.75 to 0.11) Weight, lb ‐1.94 (‐2.80 to ‐1.17) ‐1.10 (‐1.71 to ‐0.49) Waist Circumference, cm ‐0.89 (‐1.29 to ‐0.48) ‐0.75 (‐1.10 to ‐0.40) GEE models with unstructured correlation matrix adjusted for baseline CVD risk factor, baseline DASH score, sex, race, age, education, smoking (current, former, never), physical activity, energy intake, BMI, and randomization assignment.