Real‐World Effectiveness of Semaglutide and Tirzepatide Compared With Bariatric Surgery
Avery Brown, Suhani S. Patel, Akio Kozato, Babak J. Orandi, Allan Massie, Alexander Hien Vu, Eduardo Somoza, Tony Mei, Sunita Desai, Donglan S. Zhang, Dorry Segev, Akuezunkpa Ude Welcome, Christine Ren‐Fielding, Manish Parikh, Karan R. ChhabraABSTRACT
Objective
Directly compare the real‐world effectiveness of semaglutide and tirzepatide to bariatric operations: sleeve gastrectomy and gastric bypass.
Methods
This study included adults with BMI ≥ 35 who received injectable semaglutide or tirzepatide (GLP‐1RAs) or sleeve gastrectomy or gastric bypass (bariatric surgery) at two urban health systems from 2018 to 2024. Total weight loss (TWL) was compared up to 3 years post treatment with inverse probability weighting and mixed linear models. Intention‐to‐treat (any GLP‐1RA) and per‐protocol (1 year of continuous GLP‐1RA orders) analyses were performed.
Results
Of 44,025 patients studied, bariatric surgery was associated with greater weight loss at 1, 2, and 3 years post treatment: semaglutide ( n = 25,804) TWL (95% CI): 5.4% (5.3%–5.6%), 6.5% (6.4%–6.7%), and 7.4% (7.3%–7.6%); tirzepatide ( n = 7308): 9.1% (8.9%–9.4%) and 10.8% (10.2%–11.3%); sleeve gastrectomy ( n = 8728): 24.4% (24.3%–24.6%), 22.4% (22.3%–22.5%), and 22.0% (21.8%–22.1%); gastric bypass ( n = 2185): 29.8% (29.7%–29.9%), 28.1% (28.0%–28.2%), and 28.4% (28.3%–28.5%). With 1 year of continuous GLP‐1RA, findings were: semaglutide TWL: 7.2% (7.0%–7.4%), 8.0% (7.8%–8.2%), and 8.8% (8.6%–9.0%); tirzepatide TWL: 11.7% (11.4%–11.9%) and 11.9% (11.5%–12.3%).
Conclusions
In this retrospective two‐center study, bariatric surgery was associated with greater weight loss than GLP‐1RAs among patients eligible for both options.