Hypertension
Conditions
Keywords
High Blood Pressure, Exercise, Diet, Biomarkers
Brief summary
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.
Detailed description
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.
Interventions
BEHAVIORALDASH diet
Participants in the DASH diet condition receive instruction in modifying the content of their diet to meet DASH guidelines. Participants are explicitly asked not to exercise or to attempt weight loss at this time, and to focus their attention on what they eat. Following the 2-week feeding period, participants will receive instruction on the DASH diet and feedback on their adherence to the diet in a series of half-hour, weekly small group sessions (3 to 5 participants).
BEHAVIORALDASH diet plus Weight loss
Participants in the DASH diet plus weight loss condition will receive the DASH dietary intervention as described in the DASH diet intervention and will participate in a program to promote weight loss consisting of 2 components: Supervised Aerobic Exercise and CBWL (Cognitive Behavioral Weight loss). During supervised exercise participants will exercise 3x/week under medical supervision at the Duke Center for Living. A trained exercise physiologist will supervise all exercise sessions, and will obtain exercise BP measurements to make sure that BP is not abnormally elevated. For the CBWL participants will meet in small groups of 3-5 patients for instruction in weight management techniques. CBWL will include Appetite Awareness Training (AAT), a self-monitoring strategy developed to provide more specific guidelines regarding how much to eat. Individuals learn to identify moderate hunger and fullness and use these internal cues to guide their eating.
Sponsors
National Heart, Lung, and Blood Institute (NHLBI)
Duke University
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
SINGLE (Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
35 Years to No maximum
Healthy volunteers
Yes
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
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Blood pressure | 4 months |
Secondary
| Measure | Time frame |
|---|---|
| Ambulatory blood pressure,vascular function,left ventricular geometry, glucose tolerance,body composition, quality of life | 4 months |
Countries
United States
Outcome results
None listed