ENCORE: Exercise and Nutritional Interventions for Cardiovascular Health (ENCORE)

July 11, 2014 updated by: Duke University

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.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

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.

Study Type

Interventional

Enrollment (Actual)

144

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • United States
    • North Carolina
      • Durham, North Carolina, United States, 27710
        • Duke University

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

35 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

Yes

Genders Eligible for Study

All

Description

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

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Single

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
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.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Time Frame
Blood pressure
Time Frame: 4 months
4 months

Secondary Outcome Measures

Outcome Measure
Time Frame
Ambulatory blood pressure,vascular function,left ventricular geometry, glucose tolerance,body composition, quality of life
Time Frame: 4 months
4 months

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Duke University

Collaborators

National Heart, Lung, and Blood Institute (NHLBI)

Investigators

  • Principal Investigator: James A. Blumenthal, Ph.D., Duke University

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

October 1, 2003

Primary Completion (Actual)

July 1, 2009

Study Completion (Actual)

July 1, 2013

Study Registration Dates

First Submitted

December 10, 2007

First Submitted That Met QC Criteria

December 10, 2007

First Posted (Estimate)

December 12, 2007

Study Record Updates

Last Update Posted (Estimate)

July 14, 2014

Last Update Submitted That Met QC Criteria

July 11, 2014

Last Verified

November 1, 2013

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • Pro00007858
  • 5R01HL074103 (U.S. NIH Grant/Contract)
  • 4842 (Duke legacy protocol number)

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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