Skip to main content
OpenTrials
Completed

NCT Number: NCT02207777

Weight Loss-Independent Metabolic Effects of Roux-En-Y Gastric Bypass in Diabetes

For this purpose, we will compare the effects of targeted 16-18% (with a range of 16-25%) weight loss induced by Roux-en-Y Gastric bypass (RYGB) surgery with the same weight loss induced by a low-calorie diet (LCD) on liver and skeletal muscle insulin sensitivity, beta-cell function, and 24-hour metabolic homeostasis in obese subjects with or without T2D.

Completed

Looking for future studies?

Notify Me

Key information

Conditions

Obesity Body Weight Body Weight Changes Diabetes Mellitus Diabetes Mellitus, Type 2 Endocrine System Diseases Glucose Metabolism Disorders Metabolic Diseases Nutrition Disorders Nutritional and Metabolic Diseases Overnutrition Overweight Pathological Conditions, Signs and Symptoms Signs and Symptoms Type 2 Diabetes Weight Loss

Age range

25 year–65 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Washington University School of Medicine

St Louis, Missouri, 63110, United States

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

For RYGB group:

  • Scheduled for this bariatric surgery
  • Body Mass Index (BMI) 34-55 kg/m²
  • Type 2 Diabetes
  • Signed informed consent

For Low-Calorie Diet group:

  • BMI 34-55 kg/m²
  • Type 2 Diabetes and Non-Diabetics
  • Signed informed consent

Exclusion criteria

For both RYGB & Low-Calorie Diet groups

  • Regular use of tobacco products
  • Previous intestinal resection
  • Pregnant or breastfeeding
  • Evidence of significant organ system dysfunction or disease other than T2D
  • Use of any medication that might, in the opinion of the investigator, affect metabolic function
  • Exercise ≥90 minutes per week

Treatment and study plan

Roux-en-Y gastric bypass surgery

Procedure

A surgical procedure to help subjects lose approximately 16-18% (with a range of 16-25%) of their body weight.

Low-calorie diet

Behavioral

Subjects will meet with a dietitian and/or behaviorist over approximately 6 months to lose approximately 16-18% (with a range of 16-25%) of their body weight.

Primary outcomes

  1. Changes in hepatic insulin sensitivity

    Time frame: 6 months (before and after targeted weight loss)

    The outcome will be assessed by hyperinsulinemic-euglycemic-pancreatic-clamp procedure before and after weight loss.

Secondary outcomes

  1. Changes in skeletal muscle and adipose tissue insulin sensitivity

    Time frame: 6 months (before and after targeted weight loss)

    The outcome will be assessed by hyperinsulinemic-euglycemic-pancreatic-clamp procedure before and after weight loss.

  2. Changes in Beta-cell function

    Time frame: 6 months (before and after targeted weight loss)

    The outcome will be assessed as the product of beta-cell glucose sensitivity (ratio of post-meal insulin secretion rate to post-meal plasma glucose) during mixed-meal test and whole-body insulin sensitivity before and after weight loss.

  3. Changes in glucose kinetics (glucose concentration and rate of appearance into the systemic circulation) in response to mixed-meal ingestion

    Time frame: 6 months (before and after targeted weight loss)

    The outcome will be measured by using dual glucose tracer mixed meal metabolic test and serial blood sampling for 4 hours before and after weight loss

  4. Changes in 24-hour plasma glucose profile

    Time frame: 6 months (before and after targeted weight loss)

    The outcome will be determined by obtaining serial plasma glucose concentration measurements for 24 hours before and after weight loss

  5. Changes in 24-hour plasma insulin profile

    Time frame: 6 months (before and after targeted weight loss)

    The outcome will determined by obtaining serial plasma insulin concentration measurements for 24 hours before and after weight loss

  6. Changes in 24-hour plasma free fatty acid profile

    Time frame: 6 months (before and after targeted weight loss)

    The outcome will determined by obtaining serial plasma free fatty acid concentration measurements for 24 hours before and after weight loss

  7. Changes in body fat mass

    Time frame: 6 months (before and after targeted weight loss)

    The outcome will be measured by using dual-energy X-ray absorptiometry before and after weight loss

  8. Changes in intra-abdominal adipose tissue volume

    Time frame: 6 months (before and after targeted weight loss)

    The outcome will be measured by using magnetic resonance imaging before and after weight loss

  9. Changes in intrahepatic triglyceride content

    Time frame: 6 months (before and after targeted weight loss)

    The outcome will be measured by using magnetic resonance imaging before and after weight loss

  10. Changes in fat free mass

    Time frame: 6 months (before and after targeted weight loss)

    The outcome will be measured by using dual-energy X-ray absorptiometry before and after weight loss

Sponsors and collaborators

Lead sponsor

Washington University School of Medicine

Other

Collaborators

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

Registry information

Acronym: RBD-T2D

Important dates

Study start
2014
Primary completion
2019
Study completion
2019
First posted
Aug 4, 2014
Registry last updated
Jul 20, 2025

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

Related clinical trials

Published trials that share one or more normalized conditions with this study.