In a retrospective study, semaglutide use leading up to bariatric surgery was not linked with greater weight loss a year after surgery.
Rates of diabetes remission and complications were also comparable between semaglutide users and controls.
Previous studies have found that taking semaglutide after surgery can help patients shed more pounds.
Taking a GLP-1 receptor agonist prior to bariatric surgery may not boost long-term weight loss and metabolic benefits, a retrospective case-control study suggested.
Patients who received preoperative semaglutide (Ozempic, Wegovy) for 24.4 weeks lost a median of 4% body weight leading up to their bariatric surgery. Including this preoperative weight loss, these patients had greater combined total weight loss at postoperative month 3 compared with controls who didn't receive the GLP-1 drug (roughly 22% vs 15% total weight loss).
However, patients who didn't take semaglutide beforehand quickly caught up and had no difference in combined total weight loss at months 6, 9, and 12. At month 12, the combined total weight loss was 23% in the preoperative semaglutide group compared with 26% in controls, Eric G. Sheu, MD, PhD, of Brigham and Women's Hospital in Boston, and colleagues reported in JAMA Surgery.
At months 6, 9, and 12, neoadjuvant semaglutide users ended up losing significantly less weight from surgery alone (median 21% vs 26% at month 12, P=0.008).
"You might expect patients to lose more weight if they take a medication prior to surgery. But we were surprised to find that the group of patients who went on medicines first, and then had surgery, actually had the same combined total weight loss. This contrasts with previous studies that have found that taking semaglutide after surgery can further help patients lose weight," Sheu said in a statement.
"We will need to conduct more research to answer the remaining questions, but there's at least a suggestion that the most effective weight-loss strategy isn't as simple as 1 + 1 = 2," he added. "The order of strategies may be key."
"We are trying to figure out the best timing for these strategies to maximize their effectiveness and safety," Sheu continued. "When a patient should start the medicine, when they should stop taking it before surgery, and when they should have the surgery are things that still need to be evaluated. We also need to understand if the type of bariatric surgery matters for how patients respond to the medicines."
The single-center study compared 182 patients who received semaglutide before bariatric surgery from 2017 to 2024 with 182 controls who did not receive the GLP-1 agonist before their bariatric surgery. Using propensity-score matching, patients were matched prior to surgery based on age, race, preoperative body mass index, diabetes status, and surgical procedure. The majority of patients underwent sleeve gastrectomy and only around 10% underwent Roux-en-Y gastric bypass. Semaglutide users were taking a median dose of 1 mg per week.
Average age at surgery was 45 years, 77.5% were female, and 74% were white. The preoperative semaglutide group and controls had comparable baseline median weights (266 lb vs 259 lb) and BMIs (42.6 vs 43).
Most patients had prediabetes or diabetes at baseline. Median HbA1c levels were similar in patients with preoperative semaglutide compared with controls prior to surgery (5.8% vs 6.0%) and 1 year after surgery (5.5% vs 5.7%). The proportion of patients who achieved diabetes remission after a year was numerically higher in semaglutide users but not significantly different (12.6% vs 5.1%).
Rate of early major postoperative complications including bleeding, leak, infection, reoperation, readmission, and operative times also didn't differ between the groups.
Those who received semaglutide lost a similar amount of weight whether they were deemed "good" (achieved ≥20% weight loss) or "poor" (<20%) bariatric surgery responders. Also, those deemed "good" (>5% weight loss) and "poor" (<5%) semaglutide responders had similar weight loss with surgery.
Semaglutide wasn't approved for obesity at higher doses until 2021, and therefore maximum weight-loss doses were often not reached by patients, Sheu's group pointed out. Also, since the cohort was primarily comprised of sleeve gastrectomy patients, the findings may not be generalizable to other bariatric procedures.
author['full_name']
Kristen Monaco is a senior staff writer, focusing on endocrinology, psychiatry, and nephrology news. Based out of the New York City office, she’s worked at the company since 2015.
Disclosures
Sheu reported receiving personal fees from Cine-Med and Vicarious Surgical, nonfinancial support from Intuitive Surgical, grants from the NIH, and holding three pending patents for CA7S and related pathways for treatment of obesity and diabetes. Co-authors reported relationships with Ethicon and AltrixBio.
Primary Source
JAMA Surgery
Source Reference: Mathur V, et al "Neoadjuvant semaglutide, bariatric surgery weight loss, and overall outcomes" JAMA Surg 2025; DOI: 10.1001/jamasurg.2025.0001.