A new study found that patients who used GLP-1 medications such as Ozempic or Wegovy before bariatric surgery lost roughly the same amount of weight one year after the procedure as those who did not use the drugs beforehand.
According to Healthline, researchers analyzed data from 383 people who underwent bariatric surgery at a single center between 2022 and 2024. Of those patients, 92, or about 24 percent, were using a GLP-1 medication before surgery. The majority were using semaglutide, the active ingredient in both Ozempic and Wegovy.
At the 12-month mark, patients who had used GLP-1 medications before surgery lost an average of 24 percent of their total body weight. Those who had not used the medications lost an average of 25 percent. The difference was not statistically significant.
Researchers also tracked diabetes control, postoperative complications, length of hospital stay, and emergency department visits. They found no significant differences in any of those categories between the two groups.
The two groups were similar in age, body mass index, and sex. However, the GLP-1 group had a higher rate of diabetes and a higher average hemoglobin A1C level going into surgery. That group also had a lower rate of smoking.
The study did find some factors that were linked to greater weight loss overall. Patients with a higher BMI before surgery and male patients both tended to lose a greater percentage of body weight. Having diabetes or undergoing a sleeve gastrectomy, a specific type of bariatric surgery, was associated with lower weight loss percentages.
Mir Ali, MD, a bariatric surgeon and medical director of MemorialCare Surgical Weight Loss Center at Orange Coast Medical Center in Fountain Valley, California, said the results were not unexpected. He was not involved in the research.
"Because people tend to lose a certain percentage of their starting weight after bariatric surgery, it makes sense that patients who begin at a similar BMI would be expected to lose a similar amount of weight. So, in that context, the study's findings are not particularly surprising," he told Healthline.
Ali also pointed out a limitation in the study's design. The research did not account for weight patients may have already lost from GLP-1 medications before they went into surgery. That means some patients in the GLP-1 group may have arrived at surgery already lighter than they would have been otherwise, which could affect how the post-surgery numbers look.
The study was published on August 12. Researchers and outside experts both noted that the findings do not eliminate potential uses for GLP-1 medications around the time of bariatric surgery. The drugs may still help some patients lose weight before the procedure or manage weight regain in the months and years after surgery.
