Changes in Insulin Sensitivity After Weight Loss

Sponsor

Columbia University (Other)

Overall Status

Completed

CT.gov ID

NCT00627484

Collaborator

National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) (NIH)

119

Enrollment

Location

159.5

Actual Duration (Months)

0.7

Patients Per Site Per Month

Study Details

Study Description

Brief Summary

This study is designed to compare the changes in insulin sensitivity as well as gastrointestinal hormone levels in diabetic and non-diabetic obese individuals who are undergoing weight loss procedures. The main hypothesis of this study is that weight loss induced by gastric bypass will induce a greater improvement in insulin sensitivity compared with gastric banding or low calorie diet. Subjects will be studied before and after weight loss. Studies consist of intravenous glucose tolerance test, body composition analysis, meal test, and energy expenditure.

Condition or Disease	Intervention/Treatment	Phase
Obesity Type 2 Diabetes Mellitus Insulin Resistance	Procedure: Gastric bypass Procedure: Gastric banding Procedure: Sleeve gastrectomy Behavioral: Very low calorie diet

Detailed Description

Patients who are scheduled for gastric bypass (GBP), sleeve gastrectomy (SG), or simple caloric restriction with gastric banding (BND) or a very low calorie diet (VLCD) will be examined at baseline weight, and when 6-10% total body weight has been lost. We will measure insulin sensitivity with an intravenous glucose tolerance test, and fasting levels of hormones that regulate food intake and insulin sensitivity, such as ghrelin, peptide YY (PYY), glucagon-like peptide 1 (GLP1) and leptin. Fat mass and skeletal muscle mass will be measured by dual photon absorptiometry (DXA). We will also measure the hormonal and thermic response to food with a liquid test meal and energy expenditure by indirect calorimetry. This measures how many calories are burned at rest and the in response to food. Subjects with diabetes will continue to be studied with the same protocol on an annual basis out to 5 years in order to determine the rate of remission of diabetes and the durability of this effect as subjects tend to regain some body weight over time.

Subjects with diabetes will also be followed every three months for the first year after the initial weight loss for HbA1c and fasting glucose levels. The results of this study may lead to new understanding about changes in insulin sensitivity, body composition and hormonal profile, as well as changes in energy expenditure with weight loss after bariatric surgery or with simple caloric restriction. With this greater understanding, new treatments for obesity and diabetes, that do not require surgery, may be developed.

Study Design

Study Type:

Observational

Actual Enrollment :

119 participants

Observational Model:

Case-Control

Time Perspective:

Prospective

Official Title:

Changes in Insulin Sensitivity After Weight Loss Induced by Diet or Bariatric Surgery

Actual Study Start Date :

Mar 1, 2005

Actual Primary Completion Date :

Jun 17, 2018

Actual Study Completion Date :

Jun 17, 2018

Arms and Interventions

Arm	Intervention/Treatment
Group 1: GBP non-diabetic Non-diabetic subjects scheduled to receive gastric bypass	Procedure: Gastric bypass NOTE: the surgery is not paid for by the study Other Names: GBP
Group 2: BND non-diabetic Non-diabetic subjects scheduled to receive gastric banding	Procedure: Gastric banding NOTE: the surgery is not paid for by the study Other Names: BND
Group 3: GBP diabetic Diabetic subjects scheduled to receive gastric bypass	Procedure: Gastric bypass NOTE: the surgery is not paid for by the study Other Names: GBP
Group 4: VLCD diabetic Diabetic subjects scheduled to receive very low calorie diet	Behavioral: Very low calorie diet Weight loss with calorie restricted liquid diet. Subject will be asked to stay in our in-patient research unit for 2-3 weeks and consume only those foods supplied by our bionutrition unit. Expected weight loss should be between 7-10% of body weight. Subjects will receive the diet at no cost and will be compensated for their time. Other Names: VLCD
Group 5: SG diabetic Diabetic subjects scheduled to receive sleeve gastrectomy	Procedure: Sleeve gastrectomy NOTE: the surgery is not paid for by the study Other Names: SG

Outcome Measures

Primary Outcome Measures

Change in Insulin Sensitivity [2-8 weeks]
Measured by frequently sampled intravenous glucose tolerance test (FSIVGTT)

Secondary Outcome Measures

Change in Body Composition [2-8 weeks]
Measured by dual energy x-ray absorptiometry (DXA)
Change in Resting Energy Expenditure [Up to 4 hrs post-meal]
Measured by indirect calorimetry using a Hood Calorimeter

Eligibility Criteria

Criteria

Ages Eligible for Study:

18 Years to 75 Years

Sexes Eligible for Study:

All

Accepts Healthy Volunteers:

Yes

Inclusion criteria:

Non-diabetic obese (BMI > 30) adult men and women between the ages of 18 and 75 scheduled to undergo
gastric bypass (GBP)
gastric banding (BND)
Type 2 diabetes (HbA1c 6-12%) adult men and women between the ages of 18 and 75 scheduled to undergo gastric bypass.
Type 2 diabetes (HbA1c 6-12%) adult men and women between the ages of 18 and 65 for weight reduction with a very low caloric diet (VLCD).
Type 2 diabetes mellitus scheduled to undergo sleeve gastrectomy (SG).

Exclusion criteria:

Pregnancy.
Age > 75 for surgery groups; Age > 65 for VLCD group.
Treatment with glucocorticoids, anti-depressants, anti-psychotics, neuroleptics, weight loss medications, experimental medication.
Greater than a 5% change in total body weight in the 90 days prior to the study.
History of untreated gallstones; hepatic or renal insufficiency, abnormal thyroid stimulating hormone (TSH).
Use of thiazolidinedione therapy.
HbA1c > 12%.
Use of dipeptidyl peptidase IV (DPP-IV) inhibitor or glucagon-like peptide 1 receptor (GLP-1R) agonist for greater than 12 months within 3 months of the study.
Fasting triglycerides > 400.
Significant cardiovascular, neurologic, renal, gastrointestinal, or hematologic disease.
Inability to comply with or understand the study protocol as ascertained by the PI.
We will not exclude individuals with body weight > 145 kg, but we do recognize that such individuals are above the table weight limitations of the dual-energy x-ray absorptiometry (DEXA) scan and body composition data will be unavailable for those individuals.