Assessment of Insulin Resistance, NAFLD, Predictors of CV Morbidity, and Subcutaneous Adipose and Visceral Adipose Gene Expression in Patients Undergoing Gastric Bypass Surgery

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: NCT01007955
Recruitment Status : Completed
First Posted : November 5, 2009
Last Update Posted : August 24, 2012
Information provided by (Responsible Party):
Richard Perugini, University of Massachusetts, Worcester

Brief Summary:

The purpose of this research is to further study the effect weight loss after gastric bypass surgery has on the heart and blood pressure and on how the body uses or metabolizes the sugars, fats and proteins we eat. Additionally, the researchers want to study fat tissue for gene patterns which may be responsible for where we carry fat on our bodies, as well as look carefully at a possible link between adipose tissue and insulin resistance. The researchers also want to evaluate the liver for the presence of fatty liver, which is common in people with obesity and is associated with insulin resistance, as well as study the liver for gene patterns which may be associated with non-alcoholic liver disease.

Evaluating cardiovascular function and endocrine function before and after gastric bypass surgery, as well as studying adipose and liver tissue may help us understand the link between obesity, insulin resistance, fatty liver disease, high blood pressure and health problems such as diabetes and heart disease. Consequently, this may help in the future by identifying those who will benefit most from gastric bypass surgery.

Condition or disease
Morbid Obesity Insulin Resistance Non-Alcoholic Fatty Liver Disease

Detailed Description:

Obesity is associated with insulin resistance and diabetes. Since both of these conditions have been implicated in cardiovascular complications, this association may explain obesity related illnesses and deaths. Gastric bypass is considered the "gold standard" surgical weightloss procedure and has been demonstrated to cure diabetes and insulin resistance. Some severely obese patients, however, have normal insulin-glucose metabolism. The differences in metabolic healthy in severely obese individuals has not been fully recognized or understood. This research will study insulin-glucose metabolism in a population of severely obese individuals undergoing gastric bypass. This investigation is based on the following hypotheses:

  1. Severely obese individuals can be categorized by degree to which insulin-glucose homeostasis is impaired.
  2. The degree of insulin resistance correlates with risk for cardiovascular disease. Weight loss in obese individuals with insulin resistance, will correlate with improvement in parameters associated with cardiovascular disease. Obese individuals with better insulin sensitivity will not have a high risk for cardiovascular disease and therefore will not experience this risk reduction in cardiovascular disease.
  3. Insulin resistance is a consequence of pathological storage of excess energy intake; therefore, individuals who are insulin resistant and obese will differ from individuals who are obese, but not insulin resistant with regards to gene expression in subcutaneous adipose tissue and visceral adipose tissue.

Subjects will be studied for evidence of end organ dysfunction and predictors of morbidity and mortality preoperatively and postoperatively. Additionally, gene expression in the subcutaneous and visceral adipose depots of subjects will be studied

Study Type : Observational
Actual Enrollment : 61 participants
Observational Model: Cohort
Time Perspective: Prospective
Official Title: Assessment of Insulin Resistance, Non-Alcoholic Fatty Liver Disease, Predictors of Cardiovascular Morbidity, and Subcutaneous Adipose and Visceral Adipose Gene Expression in Patients Undergoing Gastric Bypass: Development of a New Paradigm in Defining "Morbid Obesity" and in the Application of Bariatric Surgery
Study Start Date : November 2006
Actual Primary Completion Date : May 2012
Actual Study Completion Date : May 2012

Severely Obese
Severely obese individuals scheduled to undergo gastric bypass surgery

Primary Outcome Measures :
  1. Improvement of insulin resistance and/or diabetes [ Time Frame: Two weeks postoperatively, Six months postoperatively, One year postoperatively ]

Secondary Outcome Measures :
  1. Improvement of cardiovascular risk factors [ Time Frame: Two weeks postoperatively, Six months postoperatively, One year postoperatively ]

Biospecimen Retention:   Samples With DNA
Subcutaneous and visceral adipose tissue.

Information from the National Library of Medicine

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Ages Eligible for Study:   18 Years to 65 Years   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Sampling Method:   Non-Probability Sample
Study Population
Severely obese patients undergoing gastric bypass surgery

Inclusion Criteria:

  • Morbid Obesity
  • Scheduled to undergo gastric bypass surgery

Exclusion Criteria:

  • Pregnancy (would not be candidate for surgery)
  • Nursing (would not be candidate for surgery)

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): NCT01007955

United States, Massachusetts
UMass Memorial Medical Center
Worcester, Massachusetts, United States, 01655
Sponsors and Collaborators
University of Massachusetts, Worcester

Responsible Party: Richard Perugini, Principal Investigator, University of Massachusetts, Worcester Identifier: NCT01007955     History of Changes
Other Study ID Numbers: H-12082
First Posted: November 5, 2009    Key Record Dates
Last Update Posted: August 24, 2012
Last Verified: August 2012

Additional relevant MeSH terms:
Insulin Resistance
Liver Diseases
Fatty Liver
Non-alcoholic Fatty Liver Disease
Obesity, Morbid
Nutrition Disorders
Body Weight
Signs and Symptoms
Glucose Metabolism Disorders
Metabolic Diseases
Digestive System Diseases