Patients who used GLP-1 medications before bariatric surgery lost about the same amount of weight one year afterward as patients who went straight to the operating room, according to a study published in JAMA Surgery. Prior users lost 24 percent of their total body weight. Non-users lost 25 percent. The difference was not statistically significant.
The finding matters because clinicians expected something different and had planned accordingly. Bariatric procedures work partly by raising the body's own GLP-1 levels, which raised a reasonable question about whether patients whose GLP-1 pathways had already been stimulated by medication would get less out of surgery.
