Preoperative GLP-1 RA therapy boosts weight and fat loss before bariatric surgery without lean mass compromise.
Background
The global burden of obesity necessitates effective interventions, with bariatric surgery (BS) being a highly effective treatment. However, optimizing patient outcomes and reducing surgical risks remains a key focus. Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) are increasingly used for weight management, but their specific impact when administered preoperatively, particularly on body composition changes like fat vs. lean mass, is not well-defined. Understanding this interaction is crucial for refining patient preparation protocols and maximizing the benefits of both pharmacological and surgical approaches to weight loss.
Study Design
This retrospective observational study analyzed 86 adults undergoing bariatric surgery (BS) between 2017 and 2023. Patients were divided into two groups: those who received preoperative GLP-1 RA therapy (34.8% of patients) and those who did not. The GLP-1 RA group received either liraglutide (63.4%) or semaglutide (36.6%) for a mean duration of 21.7 ± 15.9 weeks. Surgical procedures included sleeve gastrectomy (80.2%) and gastric bypass (19.8%). The primary endpoints were changes in weight loss and body composition (fat mass, lean mass) at various time points up to 6 months post-surgery.
Results
Patients receiving preoperative GLP-1 RA therapy achieved significantly greater weight loss before surgery, with a mean reduction of 5.1% ± 4.9% compared to 2.4% ± 3.7% in the control group (p=0.005). This enhanced weight loss persisted at 1 month postoperatively, where the GLP-1 RA group showed 15.4% ± 5.2% total weight loss versus 13.0% ± 3.8% in controls (p=0.03). However, this difference in total weight loss was not sustained at 6 months post-surgery. Importantly, prior to BS, the GLP-1 RA group exhibited lower fat mass (53.3 kg [95% CI 50.7-56.0]) compared to the control group (58.6 kg [95% CI 56.6-60.5]; p=0.01).
Key Findings
- Preoperative GLP-1 RA therapy led to significantly greater weight loss before surgery (5.1% vs 2.4%; p=0.005).
- GLP-1 RA patients showed greater weight loss at 1 month post-op (15.4% vs 13.0%; p=0.03).
- Pre-surgery fat mass was lower in the GLP-1 RA group (53.3 kg vs 58.6 kg; p=0.01).
- No significant differences in lean mass or body composition were observed at 6 months post-op.
- Adverse events were mild and primarily gastrointestinal symptoms.
Why It Matters
This study provides valuable clinical evidence that preoperative GLP-1 RA therapy can optimize patient readiness for bariatric surgery by enhancing initial weight and fat loss without compromising lean mass. For clinicians, this suggests a refined protocol where GLP-1 RAs could be strategically incorporated to improve early surgical outcomes and potentially mitigate complications associated with higher body fat. For individuals considering bariatric surgery, this indicates that a period of GLP-1 RA treatment could lead to a more favorable body composition profile before the procedure. While long-term benefits require further investigation, the short-term advantages in fat reduction and preserved lean mass are a significant practical takeaway for pre-surgical management.
glp-1-agonist
bariatric-surgery
weight-loss
obesity
body-composition
liraglutide