Metabolism and Bariatric Surgery Study

Columbia University

Status: Completed

Conditions: Insulin Resistance; Obesity

Treatments: Procedure: Sleeve Gastrectomy (SG); Procedure: Roux-en-Y Gastric Bypass (RYGBP); Behavioral: Very Low Calorie Diet (VLCD)

Study type: Interventional

Funder types: Other; NIH

Identifiers

NCT03371368

AAAR3662

R01DK072011 (U.S. NIH Grant/Contract)

Details and patient eligibility

About

The purpose of this study is to determine if diet-induced weight loss causes different changes in hormones that control appetite and glucose control than surgery-induced weight loss. The overall research plan is a non-randomized prospective study of 3 different weight loss (WL) interventions and a lean and an obese healthy control group.

Full description

Weight loss (WL) improves obesity-related co-morbidities such as type 2 diabetes mellitus (DM). Unfortunately, WL through life-style interventions has a high degree of relapse and the lack of safe, effective and affordable therapies together with an increase in the prevalence of morbid obesity has led to a rise in bariatric procedures. Clinical trials in patients with DM show that improvements in glycemia vary between procedures and occur in the following order: Roux-en-Y gastric bypass (RYGB) > sleeve gastrectomy (SG) > laparoscopic adjustable gastric banding (LAGB) > medical/life-style therapy. This order mirrors the amount of WL with each intervention and is a major driver of glycemic improvement. The investigators have shown profound changes unique to RYGB and SG in levels of hormones that make up the "gut-brain" and "enteroinsular" axes. The association of some of these hormones with insulin sensitivity (IS) and glycemia, independent of WL strongly suggests that glycemic improvements after surgery occur in part through pathways that are distinct from just calorie restriction. This study builds on results showing that levels of fibroblast growth factor 19 (FGF19), a protein secreted by intestinal cells, are increased after RYGB and SG but not after low calorie diet (LCD). This difference may affect hormones that control the stress response to weight loss. The investigators will explore differences in hormones of the gut that affect appetite, body weight, and stress response in healthy lean and obese individuals. Obese individuals will also be studied before and after 15% body weight loss induced by LCD, RYGB or SG, and again at 1 year after study enrollment.

Enrollment: 70 patients

Sex: All

Ages: 18 to 65 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

Men and women Ages 18-65 Years Old

Exclusion criteria

1. Altered Sleep-wake Cycle
2. Type 1 or 2 Diabetes
3. Previous Bariatric Surgery
4. Lactose Intolerance
5. Any Special Diet restrictions.
6. Use of medications that may affect body weight at screening or during a 3-month period prior.
7. Untreated thyroid disease
8. Other medical conditions like Cushing's, acromegaly, Hearth failure, Crohn's disease, etc.
9. Pregnancy
10. Tobacco or opioid use
11. Alcohol dependence
12. > 3% weight change over the 3month period prior to screening
13. Unwillingness to maintain current level of physical activity over duration of study period

Trial design

Primary purpose: Treatment

Allocation: Non-Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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70 participants in 5 patient groups

Gastric Bypass Diabetic and Non-diabetic

Other group

Description:

Roux-en-Y gastric bypass surgery

Treatment:

Procedure: Roux-en-Y Gastric Bypass (RYGBP)

Sleeve Gastrectomy Diabetic and Non-diabetic

Other group

Description:

sleeve gastrectomy surgery

Treatment:

Procedure: Sleeve Gastrectomy (SG)

Very Low Calorie Diet Diabetic and Non-diabetic

Active Comparator group

Description:

very low calorie diet

Treatment:

Behavioral: Very Low Calorie Diet (VLCD)

Obese Control Group

No Intervention group

Description:

Non-diabetic obese subjects

Lean Control Group

No Intervention group

Description:

Non-diabetic lean subjects