GLP-1 Use Presurgery Safe but No Weight Loss Boost

Use of glucagon-like peptide 1 receptor agonists (GLP-1 RAs) prior to bariatric surgery was safe but wasn’t associated with greater weight loss than bariatric surgery alone, suggested an analysis presented at the American College of Surgeons’ Clinical Congress.

“The excitement surrounding the use of these medications has led some to suggest they may augment weight loss when used in conjunction with bariatric surgery,” Qais AbuHasan of the Indiana University School of Medicine in Indianapolis told Medscape Medical News.

However, there is little evidence to show that this is the case, despite the fact that GLP-1 RA use in the year before bariatric surgery has increased more than threefold since 2018, from 8% to 24%.

Insights, Limitations

AbuHasan and colleagues studied outcomes of 2185 patients who underwent bariatric surgery at three Indiana hospitals from 2018 to 2023. Of these, 323 (14.8%) took a GLP-1 RA preoperatively in the year preceding surgery, either for diabetes, to lose weight, or for both. Men were more likely than women to receive the drug (21.3% vs 13.6%).

The team found no significant differences in 30-day postoperative outcomes — that is, hospital readmissions, emergency department visits, and complications — between patients who preoperatively used GLP-1 RAs vs those who did not.

Similarly, there was no significant between-group difference in the percentage of excess weight loss at 1 year postoperatively (median 56.8% vs 60.8%).

Furthermore, AbuHasan said, “Our results indicate no significant differences in GLP-1 RA use based on patients’ clinical and social characteristics, such as the surgery patients undergo or their insurance status.”

Nevertheless, he added, “While these findings are interesting, more research is still needed to identify the utility of [GLP-1 RA] use in the perioperative period. Our study provides valuable insights into [their] use before bariatric surgery, but it has limitations that future studies may investigate.”

That research could include, he suggested, identifying in advance patients who would potentially benefit from using the medications — for example, those with a higher body mass index; controlling for the type of GLP-1 RA, the dose, the duration of use, and the time of initiation before bariatric surgery; and more evidence regarding the safety of the dual approach.

“Future data will help clarify the role of GLP-1 RAs, enabling clinicians to better equip patients with effective tools to support their weight loss journey,” AbuHasan concluded.

Combination Is Cost-Effective

In a separate presentation at the meeting, researchers said that the newer weight loss drugs are cost-effective in the long term only when combined with bariatric surgery.

Joseph Sanchez, MD, a general surgery resident at Northwestern Medicine, Chicago, and colleagues conducted a cost-effectiveness analysis of GLP-1 RA therapy with semaglutide or liraglutide alone and with bariatric surgery — gastric bypass or sleeve gastrectomy — alone. They also studied the cost-effectiveness of bariatric surgery in conjunction with a GLP-1 RA to prevent weight regain.

The researchers predicted the costs of each of these treatments until death (up to 50 years) for thousands of patients from the findings of different clinical trials conducted throughout the United States.

At $17,400-$22,850, the estimated cost of bariatric surgery exceeded the average yearly cost of $9360-$16,200 for a GLP-1 RA. However, compared with these drugs alone, bariatric surgery added approximately two quality-adjusted life years (QALYs) and would save a patient more than $9000 to earn an adequately healthy year of quality life.

In contrast, a GLP-1 RA combined with bariatric surgery would save more than $7200 per QALY vs surgery alone and add more than five QALYs.

“As evidence of health benefits of GLP-1 RA continues to come out, insurance companies will have to decide whether they will cover these medications and in which case scenarios,” Anne Stey, MD, the study’s principal investigator and an assistant professor of surgery at Northwestern Medicine, said in a statement.

“Understanding if and how these different obesity management options are cost-effective is critical to ensure as many people have access to these medications as possible.”

The studies received no external funding, and the authors did not report any disclosures.

Marilynn Larkin, MA, is an award-winning medical writer and editor whose work has appeared in numerous publications, including Medscape Medical News and its sister publication MDedge, The Lancet (where she was a contributing editor), and Reuters Health.