Use of Glucagon-Like Peptide-1 Agonists Among Individuals Undergoing Bariatric Surgery in the US

Importance: Although randomized and well-controlled observational studies demonstrate the efficacy of glucagon-like peptide-1 receptor agonists (GLP-1s) for weight management after bariatric surgery, little is known regarding the frequency and predictors of such use. Objective: To characterize the use of and factors associated with GLP-1 initiation among US adults undergoing bariatric surgery. Design, Setting, and Participants: This retrospective cohort study was conducted using a national multicenter database of electronic health records of approximately 113 million US adults. Adults undergoing bariatric surgery from January 2015 to May 2023 who did not use GLP-1s during the 12 months prior to surgery were eligible for inclusion. Data were analyzed from October 2024 to May 2025. Exposures: Sociodemographic factors (age, sex, race, region, etc) and clinical factors (bariatric surgery procedures, body mass index [BMI, calculated as weight in kilograms divided by height in meters squared], comorbidities, comedications). Main Outcomes and Measures: The primary outcome was GLP-1 initiation after bariatric surgery, first characterized using descriptive statistics. Cox proportional hazards models were then used to identify baseline patient characteristics associated with GLP-1 initiation. Time-dependent Cox models were also used to examine the association of postsurgery BMI with GLP-1 initiation. Results: Among 112 858 individuals undergoing bariatric surgery, mean (SD) age was 45.2 (12.9) years, and 88 994 individuals (78.9%) were female. By self-reported race, 1210 individuals (1.1%) were Asian, 24 941 (22.1%) were Black or African American, 72 423 (64.2%) were White, and 14 284 (12.6%) reported other race (American Indian or Alaska Native, Native Hawaiian or Other Pacific Islander, or unknown). A total of 15 749 individuals (14.0%) initiated GLP-1s after surgery, with 3391 (21.5%) beginning within 2 years of surgery and the remainder initiating during postsurgical years 3 to 4 (5082 [32.3%]), years 5 to 6 (3964 [25.2%]), or beyond (3312 [21.0%]). The overall median (IQR) BMI before GLP-1 initiation was 42.0 (38.3-45.6). In regression models, female patients (adjusted hazard ratio [aHR], 1.61; 95% CI, 1.54-1.69), those undergoing sleeve gastrectomy (aHR, 1.42; 95% CI, 1.37-1.47), and those with type 2 diabetes (aHR, 1.34; 95% CI, 1.28-1.39) were more likely to initiate GLP-1s than their counterparts. Each 1-unit increase in postsurgical BMI was associated with an 8% increase in likelihood of GLP-1 initiation (aHR, 1.08; 95% CI, 1.08-1.08). Conclusions and Relevance: In this retrospective cohort study using a nationwide database, among a cohort of US adults undergoing bariatric surgery, approximately 1 in 10 initiated a GLP-1. Initiation was greater among women, those undergoing sleeve gastrectomy, and individuals with larger BMI regain than among their counterparts.