Does Taking GLP-1 Drugs Before Bariatric Surgery Affect Long-Term Outcomes? | Research

The takeaway

Preoperative GLP-1 therapy before bariatric surgery was evaluated for its impact on weight loss and complications over three years.

3-year follow-up
Long-term outcomes tracked after bariatric surgery in patients with and without preoperative GLP-1 use

What the researchers found

Propensity-matched analysis evaluated whether preoperative GLP-1 use affects bariatric surgery outcomes over three years.

Why it matters

As more patients try GLP-1 drugs before surgery, knowing whether prior medication use helps or hinders surgical outcomes is critical.

The numbers in context

N=215 (54 GLP-1, 161 non-GLP-1); pre-op TWL 3.7%; 12-month TWL: 29.8% vs 28.1%; 24-month: 28.9% vs 27.2%; 36-month: 26.9% vs 25.4%.

How the study worked

Retrospective cohort with propensity score matching (1:1) comparing preoperative GLP-1 users vs. non-users after RYGB or SG.

Who was studied

Adults who underwent RYGB or sleeve gastrectomy (2015-2021)

What this study cannot tell us

Retrospective design with potential unmeasured confounders despite propensity matching. Excluded revision surgeries and postoperative GLP-1 use.

How to read the evidence

Retrospective cohort with propensity matching — good methodology for observational research but cannot replace a randomized trial.

When this study was published

Published in 2025, addressing a rapidly evolving clinical question in obesity treatment sequencing.

The bigger picture

This addresses the evolving treatment sequencing question — whether GLP-1 drugs complement or compete with bariatric surgery.

Questions still open

Should GLP-1 therapy be routinely offered before bariatric surgery?
Does preoperative weight loss via GLP-1 drugs reduce surgical complications?

Common questions

Should I try GLP-1 drugs before bariatric surgery?

This study evaluated that exact question. Some patients use GLP-1 drugs first, then pursue surgery — the impact on long-term outcomes was analyzed.

Why do patients switch from GLP-1 drugs to surgery?

Reasons include insufficient weight loss with medication alone, desire for more durable results, or difficulty maintaining medication access.

Read the original research

Surgical Outcomes in Patients with Preoperative GLP-1 Therapy: A Retrospective Analysis.

Obesity surgery, 35(9), 3847-3857

View on PubMed ↗Publisher’s paper ↗

Citation

Poljo, Adisa; Reichl, Jakob J; Bürgi, Simon; Dirnberger, Amanda S; Schneider, Romano; Klasen, Jennifer M; Billeter, Adrian T; Müller, Beat P; Peterli, Ralph; Kraljević, Marko. (2025). Surgical Outcomes in Patients with Preoperative GLP-1 Therapy: A Retrospective Analysis.. Obesity surgery, 35(9), 3847-3857. https://doi.org/10.1007/s11695-025-08136-5