Effects of Caloric Restriction Alone Versus Postoperative Caloric Restriction Following Bariatric Surgery on Glucose Metabolism in Patients With Diabetes Mellitus
| Status: | Completed |
|---|---|
| Conditions: | Obesity Weight Loss, Diabetes |
| Therapuetic Areas: | Endocrinology |
| Healthy: | No |
| Age Range: | 18 - 60 |
| Updated: | 3/24/2019 |
| Start Date: | February 22, 2010 |
| End Date: | May 22, 2013 |
Background:
- Bariatric surgery is the most effective way to achieve significant, long-term weight
loss. It has also been shown to be an effective therapy for obese individuals with type
2 diabetes: more than 70 percent of patients no longer need medications for diabetes
after surgery. This resolution of diabetes is predominately caused by marked weight loss
resulting in improved insulin sensitivity. However, the beneficial effects of bariatric
surgery on type 2 diabetes cannot be accounted for entirely by weight loss, because many
bariatric surgery patients have resolution of diabetes within 1 week following bariatric
surgery, even before they lose a clinically significant amount of weight.
- One possible reason for the rapid resolution of diabetes after bariatric surgery .is
that during the first week after surgery, patients can eat very little (about 300
Calories per day). It is well known that reducing calories to this level improves
diabetes. Another possibility is that changes in the flow of food through the intestines
may improve diabetes. Evidence for this comes from the observation that patients after
gastric bypass have better glucose levels than those who have gastric banding.
Researchers are interested in determining how much of the improvement in diabetes in the
first week after Roux-en-Y gastric bypass (RYGBP) surgery is due to restricting
calories, and how much is due to other factors, such as bypassing the upper part of the
small intestine.
Objectives:
- To determine the change in total body insulin sensitivity after RYGBP compared to
caloric restriction without surgery.
- To study possible reasons for improvements in diabetes after RYGBP.
Eligibility:
- Individuals 18 to 60 years of age who have a body mass index (BMI) greater than 35 and have
type 2 diabetes.
Design:
- This is not a randomized study, and patients will not receive bariatric surgery as part of
this study.
Two groups of patients will be studied: those scheduled for RYGBP surgery and those not
undergoing surgery.
- RYGBP Surgery Participants:
- Up to 3 weeks before surgery, participants will spend 2 nights and days at the
Vanderbilt University Clinical Research Center or the NIH Clinical Center for testing to
learn about how their bodies handle sugar and use energy. During the 5 days prior to
these tests, participants will be asked to not take diabetes medications, and will check
blood sugar at least twice a day.
- From 8 days before surgery, participants will begin an 800 Calorie per day liquid diet
to prepare for surgery.
- After surgery and discharge, participants will be readmitted to the Clinical Research
Center at Vanderbilt or NIH for further tests and diet monitoring. Diabetes medications
may be adjusted or stopped altogether based on the results of the tests.
- Non-surgery Participants:
- Participants will spend 2 nights and days in the NIH Clinical Center for testing to
learn about how their bodies handle sugar and use energy. During the 5 days prior to
these tests, participants will be asked to not take diabetes medications, and will check
blood sugar at least twice a day.
- After the tests, participants will begin an 800 Calorie per day liquid diet for 8 days.
- After 8 days, participants will be readmitted to the Clinical Center at NIH for 1 week
of further tests and a 300 Calorie per day diet. Diabetes medications may be adjusted or
stopped altogether based on the results of the tests.
- Bariatric surgery is the most effective way to achieve significant, long-term weight
loss. It has also been shown to be an effective therapy for obese individuals with type
2 diabetes: more than 70 percent of patients no longer need medications for diabetes
after surgery. This resolution of diabetes is predominately caused by marked weight loss
resulting in improved insulin sensitivity. However, the beneficial effects of bariatric
surgery on type 2 diabetes cannot be accounted for entirely by weight loss, because many
bariatric surgery patients have resolution of diabetes within 1 week following bariatric
surgery, even before they lose a clinically significant amount of weight.
- One possible reason for the rapid resolution of diabetes after bariatric surgery .is
that during the first week after surgery, patients can eat very little (about 300
Calories per day). It is well known that reducing calories to this level improves
diabetes. Another possibility is that changes in the flow of food through the intestines
may improve diabetes. Evidence for this comes from the observation that patients after
gastric bypass have better glucose levels than those who have gastric banding.
Researchers are interested in determining how much of the improvement in diabetes in the
first week after Roux-en-Y gastric bypass (RYGBP) surgery is due to restricting
calories, and how much is due to other factors, such as bypassing the upper part of the
small intestine.
Objectives:
- To determine the change in total body insulin sensitivity after RYGBP compared to
caloric restriction without surgery.
- To study possible reasons for improvements in diabetes after RYGBP.
Eligibility:
- Individuals 18 to 60 years of age who have a body mass index (BMI) greater than 35 and have
type 2 diabetes.
Design:
- This is not a randomized study, and patients will not receive bariatric surgery as part of
this study.
Two groups of patients will be studied: those scheduled for RYGBP surgery and those not
undergoing surgery.
- RYGBP Surgery Participants:
- Up to 3 weeks before surgery, participants will spend 2 nights and days at the
Vanderbilt University Clinical Research Center or the NIH Clinical Center for testing to
learn about how their bodies handle sugar and use energy. During the 5 days prior to
these tests, participants will be asked to not take diabetes medications, and will check
blood sugar at least twice a day.
- From 8 days before surgery, participants will begin an 800 Calorie per day liquid diet
to prepare for surgery.
- After surgery and discharge, participants will be readmitted to the Clinical Research
Center at Vanderbilt or NIH for further tests and diet monitoring. Diabetes medications
may be adjusted or stopped altogether based on the results of the tests.
- Non-surgery Participants:
- Participants will spend 2 nights and days in the NIH Clinical Center for testing to
learn about how their bodies handle sugar and use energy. During the 5 days prior to
these tests, participants will be asked to not take diabetes medications, and will check
blood sugar at least twice a day.
- After the tests, participants will begin an 800 Calorie per day liquid diet for 8 days.
- After 8 days, participants will be readmitted to the Clinical Center at NIH for 1 week
of further tests and a 300 Calorie per day diet. Diabetes medications may be adjusted or
stopped altogether based on the results of the tests.
Background
Presently it is unknown whether the rapid normalization of glucose metabolism in obese
patients with type 2 diabetes after bariatric surgery (before major weight loss occurs) is
primarily due to acute postoperative caloric restriction or due to changes in intestinal
effects on insulin secretion and sensitivity. We speculate that bypassing the stomach and
proximal small intestine affects glucose metabolism beyond simple caloric restriction, and
that the mechanisms are related to changes in hepatic and muscle insulin sensitivity, changes
in vagal afferent signals, and changes in incretins and other gut hormones.
Aim
To compare the effects of pure caloric restriction with caloric restriction early after
bariatric surgery (Roux-en-Y Gastric Bypass, RYGBP) in patients with type 2 diabetes, and to
investigate the mechanisms that explain the observed difference in glucose metabolism
Methods
In patients with type 2 diabetes we will study the short-term changes in glucose metabolism,
insulin sensitivity and gut hormone levels using a parallel group design. The non-surgical
group will be studied before and after receiving a hypocaloric diet for 6 days mimicking the
typical postoperative diet. The surgical group will be studied before and 6 days after
bariatric surgery. The primary outcome will be the change in total body insulin sensitivity
attributable to caloric restriction alone versus caloric restriction after RYGBP.
Non-surgical subjects studied at NIH may enter an optional long-term weight loss phase.
Presently it is unknown whether the rapid normalization of glucose metabolism in obese
patients with type 2 diabetes after bariatric surgery (before major weight loss occurs) is
primarily due to acute postoperative caloric restriction or due to changes in intestinal
effects on insulin secretion and sensitivity. We speculate that bypassing the stomach and
proximal small intestine affects glucose metabolism beyond simple caloric restriction, and
that the mechanisms are related to changes in hepatic and muscle insulin sensitivity, changes
in vagal afferent signals, and changes in incretins and other gut hormones.
Aim
To compare the effects of pure caloric restriction with caloric restriction early after
bariatric surgery (Roux-en-Y Gastric Bypass, RYGBP) in patients with type 2 diabetes, and to
investigate the mechanisms that explain the observed difference in glucose metabolism
Methods
In patients with type 2 diabetes we will study the short-term changes in glucose metabolism,
insulin sensitivity and gut hormone levels using a parallel group design. The non-surgical
group will be studied before and after receiving a hypocaloric diet for 6 days mimicking the
typical postoperative diet. The surgical group will be studied before and 6 days after
bariatric surgery. The primary outcome will be the change in total body insulin sensitivity
attributable to caloric restriction alone versus caloric restriction after RYGBP.
Non-surgical subjects studied at NIH may enter an optional long-term weight loss phase.
- INCLUSION CRITERIA:
1. Clinical diagnosis of Type 2 diabetes mellitus
2. Age 18-60 years
3. Body mass index greater than or equal to 35 kg/m(2)
4. Either
--a. Patients scheduled for Roux-en-Y gastric bypass at Vanderbilt University
Medical Center or University of Maryland
OR
--b. Patients matched for race, sex, BMI (plus or minus 15%), and age (plus or
minus 5 years) to RYGBP patients, above, but NOT scheduled for bariatric surgery.
5. Subjects must have an endocrinologist or primary care provider who manages their
diabetes.
EXCLUSION CRITERIA:
1. Current use of insulin
2. Use of exenatide, sitagliptin (or other dipeptidyl peptidase inhibitor),
thiazolidinediones, or experimental diabetes medication within the past 3 months
3. Medical condition that alters glucose metabolism (other than type 2 diabetes) or
weight (e.g. chronic inflammatory diseases, monogenic obesity, Prader-Willi syndrome)
4. Current use of medication that alters glucose metabolism (other than oral diabetes
medications) or weight (e.g. corticosteroids, atypical antipsychotic drugs)
5. Significant comorbidity that, in the opinion of the investigators, will increase risk
to the subject, (e.g. current treatment for cancer, renal failure)
6. Positive urine pregnancy test or plans to become pregnant during the clinical trial
7. Psychiatric or cognitive disorder that will, in the opinion of the investigators,
limit the subject's ability to comply with study procedures
8. Body weight greater than 450 lbs
9. History of previous bariatric surgical procedure or other surgery altering the length
or arrangement of the intestines (e.g. Whipple procedure)
We found this trial at
3
sites
Vanderbilt University Vanderbilt offers undergraduate programs in the liberal arts and sciences, engineering, music, education...
Click here to add this to my saved trials
University of Maryland, Baltimore Welcome to the University of Maryland, Baltimore (UMB) founded in 1807...
Click here to add this to my saved trials
9000 Rockville Pike
Bethesda, Maryland 20892
Bethesda, Maryland 20892
Click here to add this to my saved trials