Home
Search
Study Topics
Glossary
|
|
|
|
|
Sponsored by: |
National Heart, Lung, and Blood Institute (NHLBI) |
---|---|
Information provided by: | National Heart, Lung, and Blood Institute (NHLBI) |
ClinicalTrials.gov Identifier: | NCT00362908 |
The metabolic syndrome consists of five concurrent conditions which increase risk of heart disease, stroke, and diabetes. Persons with the metabolic syndrome usually have high triglyceride and low HDL levels and are overweight. Low fat, high carbohydrate diets may not provide the same cholesterol-lowering benefits to obese individuals as they do to non-obese individuals. The purpose of this study is to compare the effects of a low fat, high carbohydrate diet versus a moderate fat, moderate carbohydrate diet on the heart, blood vessels, and cholesterol levels in individuals with metabolic syndrome.
Condition | Intervention |
---|---|
Metabolic Syndrome X Dyslipidemias |
Behavioral: Moderate Fat and Moderate Carbohydrate Diet Behavioral: Low Fat and High Carbohydrate Diet |
Study Type: | Interventional |
Study Design: | Treatment, Randomized, Double Blind (Subject, Investigator), Active Control, Crossover Assignment, Efficacy Study |
Official Title: | Diets for Dyslipidemia in the Metabolic Syndrome |
Estimated Enrollment: | 72 |
Study Start Date: | September 2006 |
Estimated Study Completion Date: | June 2010 |
Estimated Primary Completion Date: | June 2010 (Final data collection date for primary outcome measure) |
Arms | Assigned Interventions |
---|---|
Group 1: Active Comparator
Subjects consume study diets in the following order:
|
Behavioral: Moderate Fat and Moderate Carbohydrate Diet
40% allowable fat diet (less than or equal to 7% saturated fat) consumed for 1 or 5 months
Behavioral: Low Fat and High Carbohydrate Diet
20% fat diet (less than or equal to 7% saturated fat) consumed for 1 or 5 months
|
Group 2: Active Comparator
Subjects consume study diets in the following order:
|
Behavioral: Moderate Fat and Moderate Carbohydrate Diet
40% allowable fat diet (less than or equal to 7% saturated fat) consumed for 1 or 5 months
Behavioral: Low Fat and High Carbohydrate Diet
20% fat diet (less than or equal to 7% saturated fat) consumed for 1 or 5 months
|
The Metabolic Syndrome is characterized by elevated insulin levels, excess body fat in the waist, and elevated levels of glucose and blood pressure, and dyslipidemia. Dyslipidemia in the Metabolic Syndrome is characterized by high levels of triglycerides, low levels of HDL cholesterol, and above average LDL and non-HDL cholesterol.
Individuals with elevated LDL cholesterol have traditionally been advised to follow a low fat, high carbohydrate diet. However, research has shown that this diet does not adequately regulate cholesterol levels in individuals with dyslipidemia. A diet consisting of more moderate amounts of fats and carbohydrates may be more beneficial for individuals with the dyslipidemia of the metabolic syndrome. The purpose of this study is to compare the effects of a diet moderate in fat and carbohydrate versus a low fat, high carbohydrate diet on the cholesterol levels, inflammatory factors and vascular response in individuals with metabolic syndrome.
During the initial screening period, participants follow an American Heart Association (AHA) Step 1 diet and cholesterol levels are tested for eligibility under the criteria of the Metabolic Syndrome. Before being randomized, eligible participants have a frequently sampled intravenous glucose tolerance test (FSIVGTT), an abdominal CT scan to measure fat content in two locations and two brachial artery reactivity tests. The FSIVGTT provides information about whether participants are insulin sensitive or insulin resistant. The CT scan measures the fat content in the abdomen and the liver. The brachial artery reactivity tests measure blood flow through the brachial artery in the arm.
This 7-month study consists of two 1-month feeding periods, a rest month between the two feeding periods and a 4-month follow-up diet in a free-living setting. In Month 1, participants are randomly assigned to follow either a moderate fat, moderate carbohydrate diet or a low fat, high carbohydrate diet. Participants receive prepared food at study visits twice a week. Weight and vital signs are measured at each study visit, and blood is collected at baseline, and Weeks 3-1/2 and 4. A brachial artery reactivity test, using an ultrasound to measure artery size and blood flow in the arm, is performed twice in Week 4. In the Month 2 rest period, participants follow an AHA Step 1 diet at home. In Month 3, participants switch to the other diet and all study procedures and evaluations are repeated as in Month 1. During the following Months 4 through 7, participants continue following the second assigned diet, but are responsible for preparing their own food. They meet with a dietician once a week for 1 month to learn how to prepare meals at home. During this 4-month period, blood collection, vital sign measurements, and review of medical history and diet continue at monthly visits. At the end of Month 7, participants again undergo two brachial artery reactivity tests.
As of July 28 2008, 132 have been screened, with 61 eligible to be randomized, 31 actively enrolled in the study, 25 completed and 5 discontinued prior to completion.
Ages Eligible for Study: | 30 Years to 75 Years |
Genders Eligible for Study: | Both |
Accepts Healthy Volunteers: | Yes |
Inclusion Criteria:
Metabolic Syndrome: individuals must have at least three of the following five criteria:
Exclusion Criteria:
Responsible Party: | University of Washington ( Robert H. Knopp, MD ) |
Study ID Numbers: | 422, R01 HL083117 |
Study First Received: | August 10, 2006 |
Last Updated: | April 27, 2009 |
ClinicalTrials.gov Identifier: | NCT00362908 History of Changes |
Health Authority: | United States: Federal Government |
Obesity Hypertension Insulin Resistance |
Obesity Metabolic Syndrome X Metabolic Diseases Insulin Inflammation Abdominal Obesity Metabolic Syndrome Hyperinsulinism |
Insulin Resistance Glucose Metabolism Disorders Metabolic Disorder Dyslipidemias Hypertension Lipid Metabolism Disorders |
Hyperinsulinism Metabolic Diseases Pathologic Processes Disease Metabolic Syndrome X |
Syndrome Insulin Resistance Glucose Metabolism Disorders Dyslipidemias Lipid Metabolism Disorders |