Background
Eff
ic
ient d
ietary
intervent
ions for pat
ients w
ith hypertens
ion
in cl
in
ical sett
ings are needed.
Objective
To assess the separate and combined influence of a physician intervention (MD-I) and a patient intervention (PT-I) on dietary intakes of patients with hypertension.
Design
A nested 2脳2 design, randomized controlled trial conducted over 18 months.
Participants
A total of 32 physicians and 574 outpatients with hypertension.
Intervention
MD-I included training modules addressing the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure hypertension management guidelines and lifestyle modification. PT-I included lifestyle coaching to adopt the Dietary Approaches to Stop Hypertension (DASH) eating pattern, reduce sodium intake, manage weight, increase exercise, and moderate alcohol intake.
Main outcome measures
Dietary intakes were measured by the Block Food Frequency Questionnaire. Concordance with the DASH dietary pattern was estimated by a DASH score.
Statistical analyses
The main effects of MD-I and PT-I, and their interaction, were evaluated using analysis of covariance.
Results
After 6 months of intervention, MD-I participants significantly increased intakes of potassium, fruits, juices, and carbohydrate; decreased intake of fat; and improved overall dietary quality as measured by the Healthy Eating Index. PT-I intervention resulted in increased intakes of carbohydrate, protein, fiber, calcium, potassium, fruits and fruit juices, vegetables, dairy and Healthy Eating Index score, and decreased intakes in fat, saturated fat, cholesterol, sodium, sweets, and added fats/oils/sweets. In addition, PT-I improved overall DASH concordance score. The change in DASH score was significantly associated with the changes in blood pressure and weight at 6 months. At 18 months, most changes reversed back toward baseline levels, including the DASH score.
Conclusions
Both MD-I and PT-I improved eating patterns at 6 months with some sustained effects at 18 months. Even though all dietary changes observed were consistent with the DASH nutrient targets or food group guidelines, only the PT-I intervention was effective in improving the overall DASH concordance score. This finding affirms the role of medical nutrition therapy in long-term intensive interventions for hypertension risk reduction and weight management and underlines the need for development of maintenance strategies. Furthermore, this study emphasizes the importance of collaborations among physicians, registered dietitians and other dietetics practitioners, and lay health advisors while assisting patients to make healthy behavior changes.
