Determinants and Consequences of Adherence to the Dietary Approaches to Stop Hypertension Diet in African-American and White Adults with High Blood Pressure: Results from the ENCORE Trial

• Type of Material: Article
• Authors: Dawn E. Epstein, Duke University Medical Center; Andrew Sherwood, Duke University Medical Center; Patrick J. Smith, Duke University Medical Center; Linda Craighead, Emory University; Carla Caccia, Duke University Medical Center; Pao-Hwa Lin, Duke University Medical Center; Michael A. Babyak, Duke University Medical Center; Julie J. Johnson, Duke University Medical Center; Alan Hinderliter, Duke University Medical Center; James A. Blumenthal, Duke University Medical Center
• Language: English
• Date: 2012-11-01
• Publisher: Elsevier
• Publication Version: Author Accepted Manuscript (After Peer Review)
• Copyright Statement: © 2012 Academy of Nutrition and Dietetics.
• License: Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International
• Final Published Version (URL): http://dx.doi.org/10.1016/j.jand.2012.07.007
• Title of Journal or Parent Work: Journal of the Academy of Nutrition and Dietetics
• ISSN: 2212-2672
• Volume: 112
• Issue: 11
• Start Page: 1763
• End Page: 1773
• Grant/Funding Information: This publication was made possible by Grant Number 5UL1RR024128-03 from the National Center for Research Resources (NCRR); a component of the National Institutes of Health (NIH); and NIH Roadmap for Medical Research.; Supported by grants from the National Heart, Lung, and Blood Institute (HL074103); and the General Clinical Research Center; National Institutes of Health (M01-RR-30).
• Keywords: Diet, Reducing; African Americans; Exercise; Female; Hypertension; Overweight; Male; Guideline Adherence; Middle Aged; Treatment Outcome; Patient Compliance; Linear Models; Weight Loss; Diet, Sodium-Restricted; European Continental Ancestry Group; Humans
• Research Categories: Psychology, Behavioral; Health Sciences, Medicine and Surgery; Health Sciences, Nutrition

Abstract

Background: Although the Dietary Approaches to Stop Hypertension (DASH) diet is an accepted nonpharmacologic treatment for hypertension, little is known about what patient characteristics affect dietary adherence and what level of adherence is needed to reduce blood pressure (BP). Objective: Our aim was to determine what factors predict dietary adherence and the extent to which dietary adherence is necessary to produce clinically meaningful BP reductions. Design: Ancillary study of the ENCORE (Exercise and Nutrition Interventions for Cardiovascular Health) trial-a 16-week randomized clinical trial of diet and exercise. Participants/setting: Participants included 144 sedentary, overweight, or obese adults (body mass index 25 to 39.9) with high BP (systolic 130 to 159 mm Hg and/or diastolic 85 to 99 mm Hg). Intervention: Patients were randomized to one of three groups: DASH diet alone, DASH diet plus weight management, and Usual Diet Controls. Main outcomes measures: Our primary outcomes were a composite index of adherence to the DASH diet and clinic BP. Statistical analyses performed: General linear models were used to compare treatment groups on post-treatment adherence to the DASH diet. Linear regression was used to examine potential predictors of post-treatment DASH adherence. Analysis of covariance was used to examine the relation of adherence to the DASH diet and BP. Results: Participants in the DASH diet plus weight management (16.1 systolic BP [SBP]; 95% CI 13.0 to 19.2 mm Hg and 9.9 diastolic BP [DBP]; 95% CI 8.1 to 11.6 mm Hg) and DASH diet alone (11.2 SBP; 95% CI 8.1 to 14.3 mm Hg and 7.5 DBP; 95% CI 5.8 to 9.3 mm Hg) groups showed significant reductions in BP in comparison with Usual Diet Controls participants (3.4 SBP; 95% CI 0.4 to 6.4 mm Hg and DBP 3.8; 95% CI 2.2 to 5.5 mm Hg). Greater post-treatment consumption of DASH foods was noted in both the DASH diet alone (mean=6.20; 95% CI 5.83 to 6.57) and DASH diet plus weight management groups (mean=6.23; 95% CI 5.88 to 6.59) compared with Usual Diet Controls (mean=3.66; 95% CI 3.30 to 4.01; P<0.0001), and greater adherence to the DASH diet was associated with larger reductions in clinic SBP and DBP (P≤0.01). Only ethnicity predicted dietary adherence, with African Americans less adherent to the DASH diet compared with whites (4.68; 95% CI 4.34 to 5.03 vs 5.83; 95% CI 5.50 to 6.11; P<0.001). Conclusions: Greater adherence to the DASH diet was associated with larger BP reductions independent of weight loss. African Americans were less likely to be adherent to the DASH dietary eating plan compared with whites, suggesting that culturally sensitive dietary strategies might be needed to improve adherence to the DASH diet.