GLP-1 Medications Boost Weight Loss After Bariatric Surgery in Teens

Children's Hospital Los Angeles researchers found that restarting GLP-1 agonist weight-loss medications after sleeve gastrectomy surgery leads to greater weight loss and may prevent long-term weight regain in adolescents. The study, published as a research letter in JAMA Surgery, is the first major…

Study Overview and Background

Researchers at Children's Hospital Los Angeles CHLA have discovered that restarting glucagon-like peptide-1 GLP-1 agonist weight-loss medications after sleeve gastrectomy surgery is linked to greater weight loss and could help prevent long-term weight regain in adolescents. The findings were published as a research letter in JAMA Surgery, marking the first major effort to examine how two pediatric obesity treatments, bariatric surgery such as sleeve gastrectomy and GLP-1 agonists, can be effectively used together.

Pediatric obesity is a complex, chronic disease, according to Dr. Alaina Vidmar, the first author of the study and Medical Director of the Bariatric Surgery Program at CHLA. Dr. Vidmar works within CHLA's Center for Endocrinology, Diabetes and Metabolism. She noted that historically, diet, exercise, medications, and surgery have been treated as separate approaches. "Nobody has really looked into how we can bring these separate tools together," she explained.

The standard care guidelines for children and adolescents who have been on GLP-1 medications and are undergoing bariatric surgery typically recommend stopping the medication after the procedure. The guidelines advise restarting only if weight regain occurs in the following years. This approach is based on theoretical safety concerns and potential gastrointestinal issues associated with medication use after surgery, concerns that lack significant evidence to support them.

Patient-Driven Research Approach

Dr. Vidmar became aware that many of her teen patients were restarting their GLP-1 medications after surgery without informing her, and she wanted to understand their reasons. "This pushed us into realizing we needed to listen to their voices," she said. "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 was not completely effective at addressing what is known as 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. Consequently, they decided to resume medication after surgery.

These discussions led Dr. Vidmar and her colleagues to conduct a retrospective cohort study analyzing eating behavior, weight trajectory, safety, and medication use of patients who had undergone 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.

At the same time, 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.

Findings and Future Directions

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 better weight loss outcomes and no additional safety concerns, though specific numerical results were not detailed in the published letter. Dr. Vidmar noted that 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 explained. "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."

Dr. Vidmar also highlighted that CHLA's patient population, which is primarily publicly insured people of color, faces different barriers to care compared to the patient populations usually included in pediatric obesity research. This diversity adds important context to the study's findings.

As a next step, Dr. Vidmar and her team have received a five-year R01 grant from the National Institutes of Health to conduct a randomized controlled trial based on 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 said. "This work could really help us decide what the clinical practice guidelines should look like for surgery in the era of GLP-1s."

The 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. More information about the Bariatric Surgery Program at Children's Hospital Los Angeles is available on their website.

Peptides referenced: Semaglutide, Glucagon, GLP-1.