ENCORE: Exercise and Nutritional Interventions for Cardiovascular Health

This study has been completed.
Sponsor:
Collaborator:
Information provided by (Responsible Party):
Duke University
ClinicalTrials.gov Identifier:
NCT00571844
First received: December 10, 2007
Last updated: November 20, 2013
Last verified: November 2013
  Purpose

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.


Condition Intervention
Hypertension
Behavioral: DASH diet
Behavioral: DASH diet plus Weight loss

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Parallel Assignment
Masking: Single Blind (Outcomes Assessor)
Primary Purpose: Treatment
Official Title: Behavioral Treatment of High Blood Pressure

Resource links provided by NLM:


Further study details as provided by Duke University:

Primary Outcome Measures:
  • Blood pressure [ Time Frame: 4 months ] [ Designated as safety issue: No ]

Secondary Outcome Measures:
  • Ambulatory blood pressure,vascular function,left ventricular geometry, glucose tolerance,body composition, quality of life [ Time Frame: 4 months ] [ Designated as safety issue: No ]

Enrollment: 144
Study Start Date: October 2003
Study Completion Date: July 2013
Primary Completion Date: July 2009 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: DASH diet Behavioral: DASH 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).
Experimental: DASH diet plus Weight loss Behavioral: DASH 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.
No Intervention: Usual Care
Usual Care Control Group: Patients in the Usual Care control group will be asked to maintain their usual dietary and exercise habits for 4 months until they are re-evaluated. At biweekly intervals we will ask patients to describe any spontaneous changes in their eating habits or food preferences. To ensure patient safety, BPs will also be monitored biweekly by our staff.

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.

  Eligibility

Ages Eligible for Study:   35 Years and older
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   Yes
Criteria

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
  Contacts and Locations
Please refer to this study by its ClinicalTrials.gov identifier: NCT00571844

Locations
United States, North Carolina
Duke University
Durham, North Carolina, United States, 27710
Sponsors and Collaborators
Duke University
Investigators
Principal Investigator: James A. Blumenthal, Ph.D. Duke University
  More Information

Publications:
Appel LJ, Moore TJ, Obarzanek E, Vollmer WM, Svetkey LP, Sacks FM, Bray GA, Vogt TM, Cutler JA, Windhauser MM, Lin PH, Karanja N. The effect of dietary patterns on blood pressure: results from the Dietary Approaches to Stop Hypertension (DASH) clinical trial. N Eng J Med. 336:1117-24, 1997
Linden W, Chambers L. Clinical effectiveness of non-drug treatment for hypertension: a meta-analysis. Ann Behav Med. 16:35-45, 1994.
Jeffery RW. Weight management and hypertension. Ann Behav Med. 13:18-22, 1991.

Additional publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
Responsible Party: Duke University
ClinicalTrials.gov Identifier: NCT00571844     History of Changes
Other Study ID Numbers: Pro00007858 (4842), 5 R01 HL074103
Study First Received: December 10, 2007
Last Updated: November 20, 2013
Health Authority: United States: Institutional Review Board

Keywords provided by Duke University:
High Blood Pressure
Exercise
Diet
Biomarkers

Additional relevant MeSH terms:
Hypertension
Vascular Diseases
Cardiovascular Diseases

ClinicalTrials.gov processed this record on April 16, 2014