Children’s Hospital Los Angeles researchers have found that restarting glucagon-like peptide-1 (GLP-1) agonist weight-loss medications after sleeve gastrectomy surgery is associated with greater weight loss and could help prevent long-term weight regain.
The study was published as a research letter in JAMA Surgery and represents the first major effort to study how two pediatric obesity treatments—bariatric surgery and GLP-1 agonists—can be effectively used in combination.
“Pediatric obesity is a complex, chronic disease,” says Alaina Vidmar, MD, first author of the study and Medical Director of the Bariatric Surgery Program at CHLA. She works within CHLA’s Center for Endocrinology, Diabetes and Metabolism. “Historically, diet, exercise, medications, and surgery have been in silos. Nobody has really looked into how we can bring these separate tools together.”
Patients guide the study design
The standard care guidelines for children and adolescents who have been on GLP-1 medications and are having bariatric surgery is to stop medication after surgery and only restart if weight regain occurs in the following years. This is due to theoretical safety concerns and gastrointestinal issues associated with medication use after surgery—concerns that lack significant evidence.
But Dr. Vidmar became aware that many of her teen patients were restarting their medications after surgery without telling her, and she wanted to understand why.
“This pushed us into realizing we needed to listen to their voices,” she explains. “The reason this study is important is because our patients are the ones who designed it.”
While sleeve gastrectomy shrinks the stomach and helps regulate appetite and metabolism, Dr. Vidmar learned from her patients that it wasn't completely effective at addressing “food noise,” the brain’s management of when a person feels hungry or thinks about food. Many patients reported that GLP-1 medications, which mimic the GLP-1 hormone and increase the sensation of fullness, had been more effective at reducing “food noise,” so they decided to resume medication after surgery.
These discussions led Dr. Vidmar and her colleagues to begin a retrospective cohort study analyzing the eating behavior, weight trajectory, safety, and medication use of patients who underwent sleeve gastrectomy surgery since the launch of CHLA’s Bariatric Surgery Program in 2023.
The study included 53 patients who independently chose to resume GLP-1 medication use after surgery, as well as 46 patients who did not resume medication use.
Simultaneously, Dr. Vidmar started a quality improvement project in which her team began asking patients about their sensations of “food noise” just two weeks after their sleeve gastrectomy surgeries. This allowed the team to provide guidance on safely managing medication use to address “food noise.”
Key findings
Investigators found that reinitiating GLP-1 medications within three months after sleeve gastrectomy was safe and was associated with improved outcomes one year after surgery. Key findings included:
- Greater reductions in body weight (measured by percent body mass index change and excess weight loss)
- Improved eating behaviors
- No differences in safety outcomes, including emergency department visits, readmissions, reoperations, or gastrointestinal side effects.
Dr. Vidmar says the results support a comprehensive approach to treating severe obesity in youth. “Bariatric surgery is the most durable and effective treatment for severe obesity, but for youth with severe disease, we need a multimodal approach, which means combining medication and surgery over the lifespan,” she explains. This strategy targets both the physical and mental aspects of pediatric obesity, addressing not only weight loss itself, but the intrusive thoughts about food and hunger that comprise “food noise.”
She also notes that CHLA’s patient population, primarily publicly insured people of color, have different barriers to care than the patient populations usually included in pediatric obesity research.
A planned randomized trial
As a next step, Dr. Vidmar and her team received a five-year R01 grant from the National Institutes of Health to conduct a randomized controlled trial of this study.
“We’re going to do a 24-month study of 100 kids who are on the GLP-1 semaglutide—some of them will resume medication after surgery, while others will not,” she says. “This work could really help us decide what the clinical practice guidelines should look like for surgery in the era of GLP-1s.”
Study collaborators included My Vu, MS, Matthew Martin, MD, Aimee Kim, MD, Stuart Abel, MD, Harry Wong, MD, Cynthia E. Muñoz, PhD, MPH, MA, Madeleine N. Weitzner, RD, and Kamran Samakar, MD.