Obesity, Weight Loss, and Cardiovascular Disease Risk

The recruitment status of this study is unknown. The completion date has passed and the status has not been verified in more than two years.

Verified March 2013 by Tracey McLaughlin, Stanford University.
Recruitment status was: Enrolling by invitation

Sponsor:

Information provided by (Responsible Party):

Tracey McLaughlin, Stanford University

ClinicalTrials.gov Identifier:

NCT00186459

First received: September 13, 2005

Last updated: March 12, 2013

Last verified: March 2013

History of Changes

Tracking Information

First Received Date ^ICMJE

September 13, 2005

Last Updated Date

March 12, 2013

Start Date ^ICMJE

October 2000

Primary Completion Date

Not Provided

Current Primary Outcome Measures ^ICMJE

Weight loss

Original Primary Outcome Measures ^ICMJE

1. Weight loss

Change History

Complete list of historical versions of study NCT00186459 on ClinicalTrials.gov Archive Site

Current Secondary Outcome Measures ^ICMJE

Lipid/lipoprotein changes
Blood pressure changes
Insulin resistance changes
Endothelial function changes

Original Secondary Outcome Measures ^ICMJE

1. Lipid/lipoprotein changes
2. Blood pressure changes
3. Insulin resistance changes
4. Endothelial function changes

Current Other Outcome Measures ^ICMJE

Not Provided

Original Other Outcome Measures ^ICMJE

Not Provided

Descriptive Information

Brief Title ^ICMJE

Obesity, Weight Loss, and Cardiovascular Disease Risk

Official Title ^ICMJE

GCRC-CAP-Tracey McLaughlin, MD

Brief Summary

The goal of the study is to define the roles played by resistance to insulin-mediated glucose disposal (insulin resistance) and circulating plasma insulin concentrations in: 1) ability to lose weight; 2) reduction of risk for coronary heart disease as a result of weight loss. We hypothesize that in the setting of caloric restriction, manipulating endogenous insulin concentrations will not alter ability of subjects to lose weight, but will lead to different reduction in CHD risk factors. To test this hypothesis, two parallel studs will be performed. First, obese insulin-resistant individuals will be randomized to one of two equally-hypocaloric diets that vary moderately in proportion of carbohydrate and mono/polyunsaturated fats (lower carbohydrate diet will be associated with greater reduction in endogenous insulin secretion). Second, diabetics treated with insulin secretagogues will be compared to diabetics treated with insulin sensitizers with respect to the same outcomes (secretagogues increase insulin secretion and insulin sensitizers decrease insulin concentrations). Endpoints include weight loss, change in insulin resistance, blood pressure, lipid and lipoproteins, markers of endothelial function, daylong insulin and glucose concentrations: these will be compared, in each of the parallel studies, between the group with insulin-stimulating intervention vs the group with the insulin-sparing intervention.

Detailed Description

While obesity, insulin resistance, and diabetes are highly associated, it is not clear whether insulin resistance and compensatory hyperinsulinemia play important roles in the tendency to gain weight and/or inability to lose weight. The role of hyperinsulinemia in coronary heart disease (CHD)is also unclear. The specific aims of the proposed research are as follows:

To compare insulin resistant versus insulin sensitive nondiabetic overweight individuals with respect to their ability to lose weight on a low calorie diet. CHD risk factors before and after weight loss will also be assessed to determine the degree to which insulin resistance is associated with CHD risk, as well as the impact that differences in insulin resistance have on the metabolic benefits of weight loss
To determine if weight loss and its associated metabolic benefits vary as a function of the relative amounts of dietary fat and carbohydrate in hypocaloric diets. Because high carbohydrate diets increase insulin secretion, the relationship between dietary composition and change in circulating insulin concentrations will be analyzed with respect to both weight loss and CHD risk factors.
To quantify and compare the improvement in glycemic control and CHD risk factors associated with weight loss in obese type 2 diabetics, while being treated with 1) an insulin secretagogue (sulfonylurea) or 2) an insulin sensitizer (thiazolidinedione). Manipulation of plasma insulin concentrations with these medications will provide a mechanism by which to evaluate the impact of circulating insulin concentrations on the described outcome measures.
A subgroup of overweight/obese premenopausal women with PCOS will be studied using two diets in crossover design with regard to macronutrient effects on endogenous hyperinsulinism. For this subgroup age range will be 18-50 years, BMI 25-50 kg/m2.
In order to increase our data and therefore increase our better understanding of fat cells and insulin resistance and changes in fat cells with weight loss we would like to increase our participant enrollment to 550 all to be enrolled at Stanford University Medical Center recruiting Bariatric participants:

Age for Bariatric patients 30-65 men and women BMI 27-no upper limit Currently we have completed all participants except the bariatric and post bariatric population and those with hypoglycemia following bariatric surgery.

The ethnic background of subjects reflects Stanford's patient population.

Study Type ^ICMJE

Interventional

Study Phase

Not Provided

Study Design ^ICMJE

Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Open Label
Primary Purpose: Prevention

Condition ^ICMJE

Obesity

Intervention ^ICMJE

Behavioral: Hypocaloric diet of varying macronutrient composition

Study Arms

Not Provided

Publications *

Not Provided

* Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.

Recruitment Information

Recruitment Status ^ICMJE

Unknown status

Estimated Enrollment ^ICMJE

550

Completion Date

Not Provided

Primary Completion Date

Not Provided

Eligibility Criteria ^ICMJE

Inclusion Criteria:

BMI 30-35
age 35-65
nondiabetic by fasting plasma glucose concentration
no active major organ diseases
insulin resistant or insulin sensitive

Exclusion Criteria:

anemia
pregnant
major organ disease
active malignancy
eating disorder
active psychiatric illness
chronic inflammatory conditions

Sex/Gender

Sexes Eligible for Study:

All

Ages

18 Years to 65 Years (Adult)

Accepts Healthy Volunteers

Yes

Contacts ^ICMJE

Contact information is only displayed when the study is recruiting subjects

Listed Location Countries ^ICMJE

United States

Removed Location Countries

Administrative Information

NCT Number ^ICMJE

NCT00186459

Other Study ID Numbers ^ICMJE

RR16071-01

Has Data Monitoring Committee

Not Provided

U.S. FDA-regulated Product

Not Provided

IPD Sharing Statement

Not Provided

Responsible Party

Tracey McLaughlin, Stanford University

Study Sponsor ^ICMJE

Stanford University

Collaborators ^ICMJE

Not Provided

Investigators ^ICMJE

Principal Investigator:

Dr Tracey Lynn McLaughlin

Stanford University

PRS Account

Stanford University

Verification Date

March 2013

^ICMJE Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP

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