Mechanisms Underlying Predictors of Success From Obesity Surgery
Status:
Active, not recruiting
Trial end date:
2021-07-01
Target enrollment:
Participant gender:
Summary
The goal of this project is to identify predictors of success in the treatment of obesity
after bariatric surgery. The specific aims of this proposal are to:
1. Employ behavioral tests of mechanisms that control food intake in normal weight
individuals, to determine which intake control mechanisms lead to changes after
Roux-en-y gastric bypass (RYGB) or sleeve gastrectomy (SG); and
2. Measure behavioral and psycho-social predictors of weight loss and food intake
reduction, so as to determine which are most predictive of successful weight loss and
food intake reduction.
3. Account for success in reduction of food intake brought about by the pattern of hormone
release, particularly glucagon-like peptide-1 (GLP-1), Peptide YY (PYY) and gastric
distention, known to underlie satiation, coupled with post-ingestive changes in
reinforcing value of food and motivation to consume.
Tests of the hypothesis will be done by measuring responses to tasting, working for, and
consuming, foods on sensory, motivational, cognitive, and physiological variables, including
amount consumed and rate of eating under standardized conditions, before surgery and at a two
year follow up visit. In addition, the inhibitor sitagliptin will be administered the night
before and day of test meal and exendin-9-39 (EX9) will be infused before and during the meal
to determine whether blockade of GLP-1 / PYY receptors after surgery reverses intake
reduction. Investigators predict that successful patients will show changes that favor
reduction in food intake, rate of eating, motivation to consume, reward value of foods, and a
hormone profile that has been shown to generate satiation and maintain reduction in intake
(e.g. increased Cholecystokinin (CCK), GLP-1, PYY, reduced ghrelin). To the extent that
psycho-social and cognitive factors may override physiological brakes to eating behavior, the
subjects may fail to achieve success, and consequently the failure may be predicted from
over-impulsiveness or inability to suppress working for rewarding food stimuli. To test these
hypotheses, a total of 83 patients will be enrolled prior to RYGB/SG and restudied 2 years
after the surgery. The sitagliptin / EX9 studies will be done in a subset of 32 completers.
To test this aim, patients will be divided into 4 groups of 19. The 4 patients from each
group with the most weight loss (% weight loss ≥35 at 2 years post-surgery, 16 patients in
total) and least weight loss (% weight loss of ≤25 at two years 16 patients in total) will be
recruited for these two additional post-operative visits within one year of completing Visit
#3 after the RYGB/SG surgery. A total of 32 patients will be recruited for visits 4 and 5.
Phase:
Phase 2
Details
Lead Sponsor:
Columbia University Icahn School of Medicine at Mount Sinai
Collaborator:
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)