Bariatric surgery more effective than GLP-1 agonist weight loss drugs, study finds

Weight loss from bariatric surgery was maintained at approximately 25% for up to ten years after surgery, while patients who received GLP-1 receptor agonists regained 50% of the weight lost within one year of stopping treatment.
man holding semaglutide injection near stomach

Weight-loss surgery produces greater and more durable weight loss than glucagon-like peptide-1 receptor agonists (GLP-1 RAs) and lifestyle interventions, a systematic review has found.

The study abstract, presented on 11 June 2024 at the American Society for Metabolic and Bariatric Surgery 2024 Annual Scientific Meeting, held in San Diego, California, revealed that the bariatric surgery procedures gastric bypass and sleeve gastrectomy demonstrated total weight loss of 31.9% and 29.5% one year after surgery, respectively.

Weight loss of approximately 25% was maintained for up to ten years after surgery.  

The systematic review analysed data from 47 studies between 2020 to 2024, using data from approximately 20,000 patients in total. It included three major randomised controlled trials for GLP-1 RAs — the ‘STEP‘, ‘SELECT‘, and ‘SURMOUNT‘ trials.

Results showed that five months of weekly semaglutide injections led to 10.6% weight loss and nine months of weekly tirzepatide injections to 21.1% weight loss.

Weight loss through continued treatment with GLP-1 RAs reached a plateau after 17–18 months at 22.5% with tirzepatide, and 9.7–14.9% with semaglutide. However, once either of these treatments were stopped, approximately 50% of the weight was regained within one year.

Researchers concluded that lifestyle interventions did not lead to sustainable weight loss.

Commenting on the review, James P Byrne, president of the British Obesity & Metabolic Surgery Society, said: “Weight loss surgery changes lives and delivers better weight loss, [and] improvements in health and quality of life than any available drug.

“Obesity is a serious health problem in the UK, with severe obesity (body mass index >40) afflicting more than 3 million people, and all safe and effective treatments have a role in the management of obesity,” he added.

“The new generation of anti-obesity medicines are game-changing for people living with obesity and those caring for and treating them … [but] surgery is the most effective long-term treatment available for managing severe obesity.

In May 2023, the government reported that 63.8% of adults in England between 2021 and 2022 were estimated to be overweight or living with obesity. According to data from the national obesity audit, published by NHS England in December 2023, 4,417 primary bariatric procedures were performed between 2022 and 2023.

GLP-1 RAs are used for managing blood glucose levels in people with type 2 diabetes mellitus, but have gained popularity for their use in weight loss. In March 2023, the National Institute for Health and Care Excellence (NICE) recommended use of semaglutide injections for weight management.

The NICE draft guidance on tirzepatide for weight management is currently open for consultation until 25 June 2024. Final guidance is expected to be published on 30 October 2024.

“The number one challenge for both of these effective treatments is access,” said Byrne.

“There is as yet no clear or consistent NHS pathway for access to GLP-1 RAs in the UK. In the UK, the majority of people using GLP-1 RAs to manage their weight have to pay for this to be prescribed privately.”

Last updated
The Pharmaceutical Journal, PJ, June 2024, Vol 312, No 7986;312(7986)::DOI:10.1211/PJ.2024.1.319979

    Please leave a comment 

    You may also be interested in