5 Reasons Why Bariatric Surgery May Beat GLP-1s for Weight Loss

Bariatric surgery is an underutilized resource and often the last line of treatment for patients with obesity and associated metabolic comorbidities.¹

The rise in popularity of glucagon-like peptide-1 receptor agonists (GLP-1 RAs) leads one endocrinologist to believe the trend will ultimately result in more people receiving bariatric surgery. The maintenance associated with GLP-1 RA increases the frequency of doctors’ visits—to adjust medication or symptoms as needed—and allows physicians to propose alternative treatments like bariatric surgery, said David Rometo, MD, clinical associate professor of medicine at UPMC Division of Endocrinology and Metabolism, in an interview with The American Journal of Managed Care^®. Currently, only 0.5% to 1.0% of eligible patients actually receive bariatric surgery, despite the positive outcomes that succeed those of GLP-1 RAs.¹

Metabolic bariatric surgery (MBS), of which there are 2 types (laparoscopic sleeve gastrectomy [LSG] and Roux-en-Y gastric bypass [RYGB]), improves weight loss, decreases the risk of recurrence, is proven to be safe and efficacious, and is more cost-effective when compared with GLP-1 RAs.

Here are 5 reasons why MBS may be a better choice.

1. Cost

In a recent study analyzing costs of MBS vs GLP-1 RAs, at the 6-month baseline period, they had similar costs, averaging $1637.35. MBS costs in the first year were higher than those of GLP-1 RAs, which researchers attributed to the immediate short-term costs of surgery. However, the overall costs of the 2-year study period show that total costs for GLP-1 RAs were $63,483.00 when compared with $51,794.04 for MBS, with a mean cost savings of $11,689 for patients who received surgery.²

Weight loss interventions are not solely for those strictly trying to lose weight but can also aid in reducing metabolic comorbidities associated with obesity. Patients with a body mass index greater than 35 are at risk for poor health outcomes like diabetes, hypertension, dyslipidemia, and obstructive sleep apnea.³ Other conditions exacerbated by obesity include knee osteoarthritis, for which recent studies found the lifetime quality-adjusted life-years (QALYs) threshold is less for MBS than GLP-1 RAs like tirzepatide and semaglutide.⁴

QALY measures the quantity of life years gained and the quality (health-related quality of life) of health outcomes. QALYs are also used when measuring cost-effectiveness thresholds and the incremental cost-effectiveness ratio of a health care intervention; common thresholds for payers often amount to $100,000 per QALY. The average total lifetime costs for both MBS surgeries were $253,750 when compared with those of tirzepatide at $282,000 and semaglutide at $276,000. However, in the secondary analysis, tirzepatide had a cost-effectiveness ratio of 46,700 per QALY when compared with semaglutide's $51,800 per QALY. Whereas RYGB had a cost-effectiveness ratio of $227,000 per QALY and LSG, $20,600 per QALY, thus significantly outperforming both GLP-1s assessed for cost-effectiveness. ⁴

“You put the cost upfront for bariatric surgery, and patients experience benefits for a long period of time,” Elena Losina, PhD, codirector of the Orthopedics and Arthritis Center for Outcomes Research at Brigham and Women’s Hospital, said in an interview with The American Journal of Managed Care^®. “Comparing those 2 strategies, then, bariatric surgery shows that it provides better benefit without exceeding the cost-effectiveness threshold. That's why it is shown to be a cost-effective option for those patients who are eligible and willing.”

2. Access

Although GLP-1 RAs may seem like the more practical option in terms of feasibility, in terms of insurance coverage, and actual accessibility, bariatric surgery outperforms them once again. In a recent study based in Denmark, GLP-1 RA utilization drops significantly in users after only 1 year.⁵ The high out-of-pocket costs for consumers and payers’ reluctance to cover them, in addition to adverse events and frequent drug shortages, make long-term utilization unattainable for most users.^1,5

Patients often encounter issues with prior authorization after the first fill, loss of manufacturer copay coupons, and out-of-pocket payments aren’t realistic for the majority of patients, further contributing to the high discontinuation rates.¹ The approved drugs for weight loss can cost anywhere between $1300 and $2300 for a month’s supply without insurance. Most first-time GLP-1 RA users—specifically receiving the drug for weight loss only—who discontinue usage after 1 year are often younger (aged 29 and under) and come from lower-income areas. Whereas the association between adverse effects and discontinuation is less than that of age and income, those who experienced adverse effects and previously received medication for gastrointestinal conditions were also more likely to discontinue usage within the first year.⁵

Medicaid and Medicare do not cover GLP-1 RAs solely for weight loss; however, after the Affordable Care Act (ACA) expanded Medicaid coverage, MBS coverage was associated with a 31.6% annual increase in elective bariatric surgery.⁶ While payers may cover GLP-1 RAs for people with obesity and comorbid conditions like heart attack, stroke, peripheral arterial disease, or fatty liver disease with stage 2 fibrosis, those who don’t have such comorbidities are ineligible.

“Most people with these medical problems don't reach the severity of these medical problems [needed to receive coverage],” Rometo said while explaining GLP-1 RAs coverage stipulations. “They've got heart disease but haven’t had a heart attack yet, and for the vast majority of people with obesity, they're just hoping that their employer, or hoping that their state Medicaid, covers these medications at all.”

MBS coverage supported by the ACA has improved positive outcomes of those who received surgery, with lasting weight loss, low risk of recurrence, and minimal adverse effects.^1,6

3. Weight Loss

Patients who underwent bariatric surgery can expect to lose approximately 25% to 30% of their total weight with low rates of surgery complications and mortality. It has also been shown to reduce the incidence of 5 comorbidities associated with obesity, which include hypertension, diabetes, hyperlipidemia, and metabolic dysfunction associated with steatotic liver disease. Nevertheless, MBS is still considered a last resort as a weight loss intervention only after a patient has not yet achieved their weight loss goal.^1,2

The rise of GLP-1 RAs coincides with the increase in people consulting their doctors specifically for the weight loss drug. However, given the long-term adherence required to maintain any significant weight loss paired with high cost, minimal coverage, and adverse effects, Rometo believes more people will receive MBS in the future.

“Because more people will be going to their doctor, starting on medicines, and then they don't tolerate the medicine, or they only get to 15% weight loss, but they wanted 25%, or they still have sleep apnea, so they need to lose more weight to get rid of it,” he said. “It's going to increase the number of people in that appropriate medicalization of obesity with comorbidities and have more people getting surgery.”

Numerous studies have demonstrated the efficacy of MBS. In a retrospective cohort study, 96% of patients who received MBS lost at least 10% of their body weight when compared to the GLP-1 RA group, in which only 45.9% reached at least 10% sustained weight loss. MBS also reduced health care utilization at follow-up when compared with GLP-1 RAs, suggesting that lifetime costs for obesity with comorbidities may be substantially lower with MBS than GLP-1 RAs.²

4. Safety & Adverse Events

GLP-1 RAs (semaglutide [Wegovy], liraglutide [Saxenda], and tirzepatide [Zepbound]) are FDA-approved, but not without adverse effects. More specifically, for those who had previously taken medication for gastrointestinal conditions, GLP-1 RAs have been observed to increase the risks of said conditions, which include biliary disease, pancreatitis, bowel obstruction, and gastroparesis.^5,7 However, they’re still efficacious in weight loss and reducing comorbidities associated with obesity.

Regarding postoperative complications, MBS was seen to have a lower incidence of mortality in patients diagnosed with diabetes for over 10 years than those who used GLP-1 RAs. Although the small difference was insignificant after adjusting for weight loss in the follow-up period.⁷

With advances in minimally invasive techniques, bariatric surgery is now considered as safe as many routine abdominal procedures, with perioperative mortality rates below 0.3%. Long-term safety data are robust, demonstrating durable improvements in comorbid conditions such as diabetes and sleep apnea, with manageable risks like micronutrient deficiencies when patients receive appropriate follow-up care. This wealth of evidence offers patients and clinicians greater clarity around expected outcomes compared with newer pharmacologic approaches, which continue to be evaluated for long-term tolerability.^1,2,7

5. Adjuvant Therapies

GLP-1 RAs are commonly used after bariatric surgery to maintain weight loss and prevent the risk of recurrence, in addition to increasing patient satisfaction post-surgery if they were unhappy with their initial weight.⁸ Recent guidelines from the American Society of Anesthesiologists regarding preoperative use determined it was safe to use before elective surgeries if used before the dose escalation period. If the escalation period succeeded the surgery, the guidelines recommended a liquid diet to minimize the risk of complications and allow time for any gastrointestinal adverse effects to cease.⁹

However, more research is required on the optimal timing of GLP-1 adjuvant usage with bariatric surgery to maximize weight loss and sustainability and reduce the risk of adverse events and recurrence.

“If you took a medicine to lose weight, the best thing to do is continue taking that medicine or another weight loss or weight maintenance medication to maintain it,” Rometo said. “If you were in a program with frequent visits to lose the weight, and that was a component of why you did so well, then being in a maintenance program that also has visits [is beneficial], so you're still following up. If you measured your portions or if you use a calorie-counting app, continue to do that so you do not regain the weight. You [have to] say, “I'm going to do that for the rest of my life.” ”

References

1. McCrear S. Bariatric surgery reduces metabolic comorbidities in patients with obesity. AJMC®. September 29, 2025. Accessed October 1, 2025. https://www.ajmc.com/view/bariatric-surgery-reduces-metabolic-comorbidities-in-patients-with-obesity

2. McCrear S. Bariatric surgery potentially superior to GLP-1 RA treatment for obesity. AJMC. September 17, 2025. Accessed October 1, 2025. https://www.ajmc.com/view/bariatric-surgery-potentially-superior-to-glp-1ra-treatment-for-obesity

3. Lim Y, Haq N, Boster J. Obesity and Comorbid Conditions. In: Treasure Island, FL: StatPearls Publishing; 2025. Accessed October 1, 2025. https://www.ncbi.nlm.nih.gov/books/NBK574535/

4. McCrear S. Tirzepatide more cost-effective than semaglutide for obesity and knee osteoarthritis. AJMC. September 15, 2025. Accessed October 1, 2025. https://www.ajmc.com/view/tirzepatide-more-cost-effective-than-semaglutide-for-obesity-and-knee-osteoarthritis

5. McCrear S. GLP-1 RA adherence shows drop-off after 1 year. AJMC. September 16, 2025. Accessed October 2, 2025. https://www.ajmc.com/view/glp-1-ra-adherence-shows-drop-off-after-1-year

6. Hanchate AD, Qi D, Paasche-Orlow MK, et al. Examination of elective bariatric surgery rates before and after the US Affordable Care Act Medicaid expansion. JAMA Health Forum. 2021;2(10):e213083. doi:10.1001/jamahealthforum.2021.3083

7. Sodhi M, Rezaeianzadeh R, Kezouh A, Etminan M. Risk of gastrointestinal adverse events associated with glucagon-like peptide-1 receptor agonists for weight loss. JAMA. 2023;330(18):1795–1797. doi:10.1001/jama.2023.19574

8. McCrear S. GLP-1 usage post bariatric surgery requires more research. AJMC. August 28, 2025. Accessed October 2, 2025. https://www.ajmc.com/view/glp-1-usage-post-bariatric-surgery-requires-more-research

9. McCrear S. GLP-1s’ preoperative use requires safety considerations. AJMC. August 15, 2025. Accessed October 2, 2025. https://www.ajmc.com/view/glp-1s-preoperative-use-requires-safety-considerations