Introduction: The safety of Glucagon like Peptide 1 Receptor Agonists (GLP1RAs) following bariatric surgery remains largely unknown. This study aims to compare the incidence of adverse events (AEs) with GLP1RAs and other anti obesity medications (AOMs) after bariatric surgery. Methods: This single center retrospective cohort included patients (ages 16, 65) if they met the following criteria: underwent laparoscopic Roux en Y gastric bypass or sleeve gastrectomy (cohort entry date) and initiated AOMs. Subjects were categorized as users of FDA approved or off label AOMs or GLP1RAs AOMs if documented as receiving the medication on the cohort entry date or after. Non GLP1RA AOMs were Phentermine, Orlistat, Topiramate, Canagliflozin, Dapagliflozin, Empagliflozin, Naltrexone, Bupropion/Naltrexone, and Phentermine/Topiramate. GLP1RAs AOMs included: Semaglutide, Dulaglutide, Exenatide, Liraglutide. Primary outcome was AEs incidence. Logistic regression was used to determine the association of AOM exposure with AEs. Results: We identified 599 patients meeting inclusion criteria (83% female, median 47.8 years old (IQR 40.9, 55.4). Median surgery to AOM duration was 30 months (IQR 0, 62). GLP1RAs were not associated with higher odds of AEs (adjusted Odds Ratio, (aOR) 1.1, [95% CI 0.5, 2.6] and 1.1 [95% CI 0.6, 2.3] for GLP1RA versus FDA approved and Off Label AOMs, respectively. AOM initiation ≥12 months after surgery was associated with lower risk of AEs compared to <12 months (aOR 0.01. [95% CI 0.0, 0.01], p<0.001). Conclusion: GLP1RAs were not associated with an increased risk of AEs compared to nonGLP1RA AOMs in patients who previously underwent bariatric surgery. Prospective studies are needed to identify the optimal timeframe for initiation of GLP1RA.

The authors have declared no competing interest.

This study was supported by the resources and funding provided by the NIH NCATS award 5UL1TR002243 03 and UL1TR000445

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