ENCORE: Exercise and Nutritional Interventions for Cardiovascular Health

Behavioral Treatment of High Blood Pressure

This study is an NIH-funded clinical trial conducted at Duke Medical Center evaluating the effects of the DASH diet alone and combined with a behavioral weight loss program on blood pressure and various vascular measures. Eligible patients must be unmedicated with blood pressure values ranging from approximately 130/85 to 159/99. Our primary hypothesis are as follows: (1) The DASH diet alone and combined with a behavioral weight management program will result in greater BP reductions than Usual Care controls at the end of the 4 month treatment period; (2) The DASH diet in combination with a behavioral weight management program will be more effective in lowering BP than the DASH diet alone; (3) The DASH diet alone and the DASH diet combined with the behavioral weight management program will result in greater improvements in cardiac, metabolic, and vascular function compared to the control condition; and (4) The combined DASH diet and weight management intervention also will be the most effective treatment in maintaining BP reductions at 1-year follow-up.

The present application seeks to extend previous findings by a) evaluating the efficacy of the DASH diet in a free-living situation; (b) considering the DASH diet alone and in combination with a behavioral weight loss program including aerobic exercise; (c) examining the impact of diet and exercise on cardiac, metabolic, and vascular function, including measures of arterial stiffness, endothelial function, baroreflex control, body composition, insulin resistance, cardiac hemodynamics, and left ventricular (LV) geometry and mass; and (d) following patients for one year to determine the longer term impact of the interventions on BP, body weight, and cardiovascular function.

Inclusion Criteria:

1. Baseline SBP 130-159 mmHg (+/- 2mmHg) or DBP 85-99 mmHg (+/- 2 mm Hg)
2. Age 35 years or older
3. BMI 25.0-39.99 kg/m², with a maximum weight of 300 lbs
4. Willing and able to participate fully in all aspects of the intervention
5. Must currently be sedentary (less than 3x/wk for 30 mins each time)
6. Informed consent

Exclusion Criteria:

1. Use of weight-loss medication and/or participation in a structured weight- loss program in the 3 months prior to 1st screening visit.
2. Regular use of an anti-hypertensive drug or other drugs that raise or lower BP and if discontinued use, must be off for 1 month before screening
3. Current use of insulin or oral hypoglycemic agents
4. Current use of medications for treatment of psychosis or manic-depressive illness.
5. ADHD medications (Ritalin/Aderol/amphetamines
6. Cardiovascular Event
7. Coronary Artery Disease
8. Congestive Heart Failure
9. Current symptoms of Angina for peripheral vascular disease
10. Cancer diagnosis (except for non-melanoma skin cancer) or treatment in past 2 years
11. Fasting blood sugar >126 mg/dl
12. Gastric Bypass/Bariatric Surgery
13. Pyschiatric hospitalization in the past 2 years.
14. Unable or willing to consume all of the dietary foods provided during the 2-week feeding.
15. Consumption of more than 21 alcoholic drinks per week or binge drinking
16. Alcoholism as determined by the Alcohol AUDIT (screening questionnaires)
17. Planning to leave the area prior to the anticipated end of participation
18. Body weight change of >15lbs in the 3 months prior to the 1st screening visit
19. Pregnant, breast feeding, or planning pregnancy prior to end of participation
20. Current participation in another clinical trial until after completion of T2
21. Investigator discretion for safety or adherence reasons
22. Controlled substance abuse