Preoperative GLP-1 receptor agonists helped patients lose more weight before bariatric surgery and improved diabetes outcomes, but were linked to more postoperative nausea without increasing major complications.
11 studies reviewedAll observational studies found GLP-1 RAs enhanced preoperative weight loss without increasing major surgical complications
What the researchers found
Across 11 observational studies, preoperative GLP-1 receptor agonist use enhanced weight loss before metabolic and bariatric surgery, allowing patients to reach surgical eligibility sooner. The drugs were associated with improved diabetes outcomes post-surgery.
However, preoperative GLP-1 RA use was linked to increased postoperative nausea. There were no significant differences in major complication rates or readmissions. Some studies noted higher surgical adhesion rates. Findings on postoperative weight loss specifically were inconsistent across studies.
Why it matters
GLP-1 receptor agonists have become enormously popular for weight loss, and many patients now arrive for bariatric surgery already taking these drugs. Understanding how preoperative use affects surgical outcomes is critical for surgeons and patients making treatment decisions. This review provides early evidence that the combination is generally safe, though more research is needed.
How the study worked
The researchers conducted a systematic review by searching four major medical databases (Web of Science, Embase, PubMed, and Scopus) for studies examining preoperative GLP-1 receptor agonist use before metabolic and bariatric surgery. They identified and analyzed 11 observational studies evaluating the effects on surgical outcomes.
What this study cannot tell us
All 11 included studies were observational, limiting the strength of causal conclusions. Findings on postoperative weight loss were inconsistent. The review does not report pooled quantitative effect sizes. Specific GLP-1 RA drugs, doses, and treatment durations likely varied across studies, making direct comparisons difficult.
How to read the evidence
This is a systematic review of 11 observational studies, which provides a broad overview of existing evidence but lacks the strength of randomized controlled trials or meta-analysis with pooled statistics.
When this study was published
Published in 2025, this is a timely review addressing the rapidly growing intersection of GLP-1 receptor agonist therapy and bariatric surgery.
The bigger picture
As GLP-1 receptor agonists become first-line obesity treatments, the question of how they interact with bariatric surgery is increasingly important. Some patients may use them as a bridge to surgery, while others may find surgery unnecessary. This review suggests the drugs can safely complement the surgical pathway, though the mixed results on postoperative weight loss raise questions about long-term combined efficacy.
Questions still open
- Does the specific GLP-1 RA drug or dosing protocol matter for optimizing preoperative outcomes?
- Why were postoperative weight loss results inconsistent — could timing of drug discontinuation play a role?
- Would randomized controlled trials confirm these observational findings?
Common questions
Is it safe to take GLP-1 drugs like semaglutide before bariatric surgery?
Do GLP-1 drugs before surgery help patients lose more weight afterward?
Read the original research
Preoperative Glucagon-Like Peptide-1 Receptor Agonists and Bariatric Surgery Outcomes: A Systematic Review.
Obesity surgery, 35(9), 3939-3946
Citation
Esparham, Ali; Sheikhbahaei, Erfan; Anari Moghadam, Hengameh; Khorgami, Zhamak. (2025). Preoperative Glucagon-Like Peptide-1 Receptor Agonists and Bariatric Surgery Outcomes: A Systematic Review.. Obesity surgery, 35(9), 3939-3946. https://doi.org/10.1007/s11695-025-08137-4