Researchers presented new data at the ASMBS Annual Meeting, comparing long-term weight loss outcomes between bariatric surgery and GLP-1 receptor agonist therapies. The findings indicate that surgery led to significantly greater weight loss over three years.
The analysis examined patients who received weekly injectable GLP-1 receptor agonists, including semaglutide and tirzepatide, or underwent bariatric procedures such as sleeve gastrectomy or Roux-en-Y gastric bypass. The study involved 51,085 patients from two large urban health systems between 2018 and 2024. Of these, 38,545 received GLP-1 medications, and 12,540 underwent bariatric surgery.
Researchers tracked total weight loss over a three-year period. To account for differences between groups, statistical adjustments were applied based on age, baseline body mass index (BMI), and comorbidities. Analyses included both intention-to-treat, which included all patients prescribed GLP-1 drugs, and per-protocol, which included only patients who remained on GLP-1 therapy for at least one year.
Bariatric surgery was associated with greater and more sustained weight loss than GLP-1 receptor agonist therapy. In the intention-to-treat analysis, surgery patients lost an average of 23.3% of total body weight after three years, while GLP-1 patients lost 4.0%. In the per-protocol analysis, surgery patients lost 22.2%, compared to 5.9% for those on GLP-1 therapy.
The groups also differed in baseline health conditions. GLP-1 patients had higher rates of diabetes, hyperlipidemia, and chronic obstructive pulmonary disease. These differences were adjusted for in the analysis.
Both GLP-1 receptor agonists and bariatric surgery are used to manage obesity and metabolic disorders. While GLP-1 medications have grown in popularity due to their less invasive nature, this study provides comparative evidence supporting bariatric surgery as a more effective strategy for long-term weight loss.
The study was conducted by researchers from multiple institutions using data collected over six years. The research was supported by the National Institutes of Health through the National Center for Advancing Translational Sciences and the National Institute of Allergy and Infectious Diseases.
Disclosures were not made available in the study abstract.
Source: ASMBS Annual Meeting