Insulin Resistance in Severely Obese Patients

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT00275223
Recruitment Status : Completed
First Posted : January 11, 2006
Last Update Posted : March 18, 2010
Information provided by:
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)

Brief Summary:
This study aims to understand the biological processes that link obesity to diseases including insulin resistance and diabetes. Our approach involves studying the health of patient undergoing weight loss either via weight reduction surgery or by medically supervised liquid formula diets. Patients must be enrolled in a weight treatment program at Emory Bariatrics, Emory University, Atlanta GA, to be eligible for this study. This study does not cover the cost of treatment at Emory Bariatrics. The hypothesis is that decreases in adipose-tissue derived factors during weight loss will be related to improvement in insulin function.

Condition or disease
Obesity Insulin Resistance Diabetes

Detailed Description:
Severe obesity affects 4.7% of the U.S. population. A significant number of these individuals suffer from impaired glucose tolerance and type II diabetes due to insulin resistance (IR). Although it is generally accepted that the accumulation of intraabdominal (IA) fat increases the risk of developing IR, the mechanisms responsible for this phenomenon are not yet understood. In addition, the role of subcutaneous (SC) fat towards the etiology of IR - protective, inert or detrimental - is still under debate. This is because SC adipose tissue releases adipocytokines (IL-6, leptin, TNF- ) that have been demonstrated to impair insulin action. In individuals who are severely obese, hyperinsulinemia may induce an exaggerated production of adipocytokines from IA compared to SC fat stores. Our specific aims are: (1) to determine relative contribution of abdominal SC fat versus IA fat to systemic levels of IL-6, leptin and TNF- in lean and in severely obese individuals; (2) to determine the effects of systemic adipocytokine concentrations on whole body as well as tissue sensitivity to insulin. Hypothesis: (a) In the context of severe obesity, IA fat produces increased quantities of IL-6, leptin and TNF- compared to SC fat; (b) In severely obese patients undergoing weight loss, whole body and tissue IR can be predicted by changes in systemic adipocytokines. Methods: Adipose tissue content of IL-6, leptin and TNF- will be determined by ELISA in biopsies obtained from IA and SC fat stores in lean and severely obese patients. Computer tomography-determined areas of IA and SC fat will be related to changes in systemic adipocytokines at baseline and 6-mo following weight loss therapy. Changes in systemic IL-6, leptin and TNF- will be assessed from measurements made at baseline and following 6-mo weight loss. For this time period we will also determine changes in whole body (via IVGTT) and tissue sensitivity to insulin (via glucose uptake into muscle and fat). Relationships between systemic adipocytokines and IR will be assessed using uni- and multivariate correlation analysis. These novel studies will determine whether hypersecretion of adipocytokines by IA versus SC adipose tissue induces IR in patients with severe obesity.

Study Type : Observational
Estimated Enrollment : 48 participants
Time Perspective: Prospective
Official Title: Insulin Resistance in Severely Obese Patients
Study Start Date : September 2004

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.

Ages Eligible for Study:   18 Years to 65 Years   (Adult)
Sexes Eligible for Study:   Female
Accepts Healthy Volunteers:   No

Inclusion Criteria:

Enrolled in weight treatment program at Emory Bariatrics

Exclusion Criteria:

Male Smoker

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT00275223

United States, Georgia
Emory University Hospital
Atlanta, Georgia, United States, 30322
Sponsors and Collaborators
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Principal Investigator: Nana Gletsu, Ph.D. Emory University

Publications of Results: Identifier: NCT00275223     History of Changes
Other Study ID Numbers: R03 DK67167 (completed)
First Posted: January 11, 2006    Key Record Dates
Last Update Posted: March 18, 2010
Last Verified: March 2010

Keywords provided by National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK):
adipose tissue

Additional relevant MeSH terms:
Insulin Resistance
Glucose Metabolism Disorders
Metabolic Diseases