A RETROSPECTIVE study conducted by Mass General Brigham researchers has found that taking semaglutide before bariatric surgery does not improve overall weight loss or safety outcomes compared to surgery alone.
Obesity is a growing global health concern, with bariatric surgery and weight-loss medications like semaglutide (Ozempic and Wegovy) being prominent treatment options. While previous studies have shown that taking semaglutide after weight-loss surgery can be effective, the impact of pre-surgical use was unknown. This study aimed to investigate whether taking semaglutide before bariatric surgery could enhance weight loss outcomes and safety for patients with obesity and metabolic disease.
The researchers analysed data from 364 patients over seven years, with 182 patients who took semaglutide before surgery matched with 182 control patients who underwent surgery without prior semaglutide use. The study found that while the semaglutide group had higher total weight loss at three months post-surgery, this advantage disappeared by the six-month mark. At 12 months, the median total weight loss was 21.0% for the semaglutide group versus 26.0% for the control group (P = .008). Safety outcomes and major postoperative complications were similar between both groups. Additionally, diabetes remission rates at one year post-surgery were comparable (12.6% vs 5.1%, P = .15).
These findings suggest that a surgery-first strategy may lead to better overall obesity treatment outcomes. The study challenges the assumption that combining medication and surgery always produces additive effects. For clinical practice, these results could inform discussions between healthcare providers and patients about the optimal sequencing of weight-loss interventions. However, the authors note limitations, including the predominance of sleeve gastrectomy procedures in the cohort and potential selection bias. Future prospective studies are needed to further examine the optimal timing and combination of semaglutide and bariatric surgery to maximise effectiveness in obesity treatment.
Katrina Thornber, EMJ
Reference
Mathur V et al. ‘Neo-adjuvant’ semaglutide reduces weight loss with bariatric surgery and does not improve overall outcomes. JAMA Surgery. 2025;DOI:10.1001/jamasurg.2025.0001.
