Feb. 11, 2023
Endoscopic sleeve gastroplasty (ESG) has become an attractive, noninvasive treatment option for patients with obesity. Meta-analyses comparing ESG with alternative treatments — including intragastric balloon insertion, surgical sleeve gastrectomy, and high-intensity diet and lifestyle modifications — have demonstrated that ESG is a safe and effective addition to the list of tools available for managing obesity.
ESG is thought to produce weight loss by reducing the stomach's capacity by approximately 80% and by altering gastrointestinal tract physiology through delayed gastric emptying (GE). However, the mechanisms of action and durability of efficacy associated with ESG are not yet well understood. To address these issues, Mayo Clinic researchers conducted a comparative prospective study, the results of which were published in Gut in 2022.
According to Eric J. Vargas Valls, M.D., M.S., first author of the article in Gut, the Mayo Clinic researchers sought to determine what types of changes occur in gastric emptying (GE), gastric motility (GM), obesity-related hormones and eating behaviors after ESG. Dr. Vargas Valls is a gastroenterologist and hepatologist at Mayo Clinic in Rochester, Minnesota, whose research includes the study of endoscopic approaches to bariatric therapies.
"We need a better way to identify which treatment approach will work best for a particular patient," explains Dr. Vargas Valls. "Obtaining a better understanding of how ESG promotes weight loss and weight maintenance could help us identify factors that show promise for individualizing obesity therapy."
Study aims and design
The single-center clinical trial involved adults with obesity randomly assigned to receive either ESG or lifestyle (LS) interventions. The substudy group included 18 participants from the ESG group and 18 from the LS interventions group.
The researchers' primary aim was to determine the changes in GE associated with ESG versus LS interventions, at three months and at 12 months. They also investigated whether a change in GE is predictive of weight loss, and assessed and analyzed the following:
- Changes in eating behaviors.
- Changes in obesity-related hormones — ghrelin, polypeptide YY (PYY) and glucagon-like peptide 1 (GLP-1).
- Changes in gastric accommodation and changes in GM.
"We hypothesized that ESG delays GE, that the GE delay correlates with weight loss, and that delay leads to minimal to no changes in obesity-related hormones, despite weight loss," explains Dr. Vargas Valls.
Study results and implications
According to Dr. Vargas Valls, the study yielded some findings that could help guide treatment choices for patients requiring weight-loss interventions. Results included the following observations:
- GE was significantly delayed in the ESG group compared with the LS interventions group, at three months and at 12 months.
- Greater GE delays at three months were associated with greater weight loss at three, six and 12 months.
- The percentage total body weight loss was significantly greater in the ESG group than in the LS interventions group at three, six and 12 months.
- GM was preserved, and fasting ghrelin, GLP-1 and PYY significantly increased 18 months after ESG.
"Our research confirmed that ESG is indeed an anatomy-sparing procedure that preserves gastric motility while producing favorable changes in gastric emptying and hormones, all of which are responsible for improving satiation and satiety, which leads to weight loss," explains Dr. Vargas Valls. "This suggests that ESG can serve as a stand-alone primary obesity management procedure or as a bridge to bariatric surgery. Because ESG leaves the stomach's blood supply and nerve innervation intact, clinicians can refer patients for the procedure without burning any bridges for future therapy. And in contrast with intragastric balloon procedures, there are minimal side effects associated with ESG, likely due to the preserved gastric motility."
Future research
Dr. Vargas Valls notes that additional research is needed to further compare ESG with traditional surgical sleeve gastrectomy and other weight-loss procedures, using sophisticated physiological testing.
"We will also take an 'omics' approach to identifying novel treatment strategies for obesity," adds Dr. Vargas Valls. "My Mayo Clinic gastroenterology and bariatric endoscopy colleagues, including Drs. Barham Abu Dayyeh and Andres Acosta, along with the Clinical Enteric Neuroscience Translational and Epidemiological Research (C.E.N.T.E.R.) Program at Mayo Clinic in Rochester, Minnesota, will play pivotal roles in several additional planned research projects."
For more information
Vargas EJ, et al. Effect of endoscopic sleeve gastroplasty on gastric emptying, motility and hormones: A comparative prospective study. Gut. In press.
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