An analysis of more than 2 million elective-surgery patients found modestly lower rates of major cardiovascular complications and postoperative infections among GLP-1 users, but cannot prove the drugs caused the benefit or resolve concerns about delayed stomach emptying.
Adults taking GLP-1 medicines before elective surgery appeared to have slightly lower rates of major heart complications and postoperative infections, according to an analysis of more than 2 million patients presented at the American Society of Anesthesiologists’ ANESTHESIOLOGY 2026 meeting in San Diego. The finding adds a new wrinkle to an already debated question about these drugs, including semaglutide and tirzepatide, which are widely used for diabetes and weight management.
The study, led by Josephine Tolan of McGovern Medical School at UTHealth Houston, drew on Epic Cosmos, a large de-identified health record database covering more than 1,700 hospitals and 40,000 clinics, according to the ASA. Researchers examined US adults who underwent elective operations lasting more than an hour and remained in hospital for at least 24 hours between January 2016 and December 2024. Of 2,028,601 patients, 145,610, or about 7%, were using a GLP-1 drug.
After matching patients with similar characteristics, the analysis found 11% lower odds of major cardiovascular complications among GLP-1 users. Those complications included heart attack, heart injury, stroke and death. The same group also had 8% lower odds of infections after surgery, including surgical site infection, urinary tract infection, pneumonia and sepsis, according to figures reported by Newsweek. In absolute terms, the difference was small: major heart-related events occurred in 1.0% of GLP-1 users versus 1.1% of non-users, while infections affected 4.9% and 5.3% respectively.
Tolan said in the ASA release that the results were encouraging, but warned that more research is needed to determine whether the medicines themselves were responsible. The study was observational, not a randomised trial, so it can show an association but not prove cause and effect. People prescribed GLP-1 drugs may differ from other surgical patients in ways that are difficult to fully adjust for, including blood sugar control, access to care, weight and other health factors.
The findings also do not settle the central anaesthesia concern around GLP-1 medicines: delayed stomach emptying. Anaesthesiologists worry that food may remain in the stomach even after standard fasting, which could raise the risk of aspiration during surgery, when stomach contents are inhaled into the lungs. Tolan told Newsweek that the new analysis does not remove that concern.
That is why existing guidance still matters more than this single study. In 2024, the ASA and four other medical societies advised that most patients can continue GLP-1 treatment before elective surgery, but that decisions should be tailored to individual risk, particularly for people early in dose escalation or those with nausea, vomiting or other stomach symptoms. For now, patients should tell their surgeon and anaesthesia team which GLP-1 they use, the dose and when they last took it, and should not start, stop or skip medication on their own.
Jessica Duncan, an obesity medicine physician and chief medical officer of Ivím Health, told Newsweek that the analysis was reassuring and hypothesis-generating, but that it did not address aspiration risk or establish causation. She said the next step is prospective research that weighs the possible benefits and risks together. Earlier work from Weill Cornell Medicine had already pointed in a similar direction, finding that active GLP-1 prescriptions in patients with diabetes were associated with fewer readmissions and wound complications after surgery. But that study, like the new one, was observational and limited in what it can prove. For now, the message for patients is straightforward: the data are mildly reassuring, but they are not a reason to change surgical plans without medical advice.
Disclaimer: This content is for informational purposes only and is not intended to be a substitute for professional medical judgment, advice, diagnosis, or treatment.
