FRI075 Single Center Retrospective Matched Cohort Study Of glp1ra-induced Weight Loss In Patients With Post-bariatric Weight Regain Vs Non-surgical Controls
Authors: Carmen Rivadeneira Ana Del , Walker Michelle , Gallop Robert , Amaro Anastassia 
Published: October 2023

Abstract
Disclosure: A. Rivadeneira: None. M. Walker: None. R. Gallop: None. A. Amaro: Advisory Board Member; Self; Novo Nordisk. Research Investigator; Self; Eli Lilly & Company, Novo Nordisk.
Background: Obesity prevalence worldwide is increasing. By 2030, almost one-fourth of US population will have severe obesity (BMI &gt;35 mg/kg2). Bariatric surgery (BS) is an effective intervention for weight loss (WL) in patients with severe obesity; weight regain (WR) remains a concern. Over one-third of patients will regain more than 25% of total WL. GLP-1 receptor agonists (GLP1RA) have been effective for WL in patients with obesity. Effectiveness and safety of liraglutide and semaglutide in patients with WR after BS were observed in several retrospective studies. The difference in response to GLP1RA in patients with and without a history of bariatric surgery has not been assessed. Objectives: We aimed to retrospectively compare amount of WL and time to nadir in BMI matched individuals with history of WR following BS and without history of surgery treated with GLP1RA. Methods: Retrospective matched cohort study of the patients referred to Penn Metabolic Medicine (PMM) clinic for non-surgical weight management. We analyzed 63 patients with history of RYGB or VSG seen between 8/2015-8/2021 for WR and who received GLP1RA. BMI matched non-surgical (NS) cohort (N=60) treated with GLP1RA was built from the PMM patients of the same period for comparison. Results: Mean weight on presentation at PMM in surgical group (SG) was 273.1 lbs, (BMI 43.5 kg/m2), and in non-surgical one (NS) 264.9 lbs (BMI 43.3 kg/m2). Nadir weight after initiation of GLP1RA in SG 241.1 lbs and controls 244 lbs, with percentage WL of 11.8% in SG and 7.86% in NS controls (p-value 0.0081). Mean time to nadir weight after initiation of GLP1RA was 17.2 months for SG, and 9.2 months in NS controls (p-value &lt;0.0001). Discussion: When treated with GLP1RA, patients with post-bariatric WR lost on average 12% of their weight and achieved nadir around 17 months. Weight matched NS controls lost less weight and entered a plateau phase faster, suggesting enhanced GLP1RA efficacy after bariatric surgery. Significant WL response to GLP1RA was similar in RYGB and VSG groups, supporting previously demonstrated GLP1RA efficacy for post-bariatric WR. Larger prospective trials are needed for confirmation. Reports suggest both RYGB and VSG increase postprandial GLP-1. Proposed WR mechanisms include hormonal changes, nutritional non-adherence, physical inactivity and maladaptive eating. Hormonal mechanisms include increase in ghrelin, decrease in GLP-1 and peptide YY, post-bariatric hypoglycemia and other pathways. Further studies are needed to elucidate the mechanism of enhanced GLP-1 RA efficacy in patients with WR after BS. The limitations of our study include a retrospective nature, modest sample size and the choice of GLP1RA limited to liraglutide, exenatide and semaglutide and guided by the subjects’ insurance plans. In the future, dual incretins will need to be studied in patients with WR after bariatric surgery.
Presentation: Friday, June 16, 2023