Authors' objectives: Bariatric surgery is the most effective treatment for obesity, but access is limited. Endoscopic obesity treatments are potentially cheaper and less invasive options, which may be similarly effective. There is currently a lack of evidence to inform decisions on whether such treatments should be considered for people living with obesity. What is the current evidence for the clinical and cost-effectiveness of endoscopic treatments compared to alternative weight management interventions for obesity? Obesity is a common disease associated with poorer quality of life (QoL), increased risk of multiple metabolic, vascular, physical and mental health complications and mortality, and significant economic impact. Bariatric surgery is currently the most effective obesity treatment for sustained long-term weight loss and improvements in obesity complications. Despite its effectiveness, access to bariatric surgery is limited due to multiple factors including lack of resources among others. Lifestyle behavioural interventions (LSIs) are known to have modest effectiveness that is difficult to sustain long term. Endoscopic obesity treatments are becoming increasingly available globally and in the UK. Compared to bariatric surgery, they are less invasive, require a shorter hospital stay and are potentially cheaper, while replicating some of the anatomical and physiological changes that occur after bariatric surgery. This makes them a potential alternative, or bridge to, bariatric surgery. It is important to determine whether endoscopic treatments are both clinically effective and cost-effective to inform decision-making from the UK NHS/Personal Social Services (PSS) perspective on their potential for treating people living with obesity.

Authors' results and conclusions: The evidence map included over 1500 records of studies of endoscopic therapies, most of which related to intragastric balloons and endoscopic sleeve gastrectomy. Three cost–utility analyses were identified, one of which was set in the United Kingdom and was used to inform the models. Laparoscopic sleeve gastrectomy is likely cost-effective compared with endoscopic sleeve gastroplasty for patients’ obesity class II and III (£10,593 per quality-adjusted life-year-gained). Endoscopic sleeve gastroplasty is likely cost-effective compared with semaglutide for patients’ obesity class I and II (£7267 per quality-adjusted life-year-gained). Semaglutide is dominant (cheaper and more effective) than intragastric balloon in patients’ obesity class I and II. Probabilistic sensitivity analysis found a degree of confidence in the estimates. The 5-year time horizon may not capture longer-term benefits from endoscopic sleeve gastroplasty or laparoscopic sleeve gastrectomy. Evidence map There were 1574 records of relevant studies included in the evidence map, with 90% of these published after 2009. Most of these records were related to single-arm studies (73%), 18% related to non-randomised controlled studies, and 9% related to RCTs. The most common endoscopic interventions were space-occupying devices (mainly IGB), restrictive procedures (mainly variations of ESG) and to a lesser extent malabsorption devices (such as duodenal–jejunal bypass liner). The most common comparators were a different endoscopic treatment (or variation of the same treatment), bariatric surgery (often LSG) and LSI, with sham procedures and pharmacotherapy less well represented. Most studies reported weight loss and/or safety outcomes but could also include changes in body composition, satiety and gastric emptying, and biomarkers of metabolic and glycaemic control. Duration of follow-up varied from 1 week to 5 years but was most frequently between 6 and 12 months. The vast majority of studies were in adults, with very few records relating to studies undertaken in children or adolescents. Patients were enrolled for weight loss prior to surgery (‘bridge to surgery’) or following weight regain after previous obesity treatment in a small proportion of studies. A limitation of the map is the reliance on abstracts only for data extraction. In terms of informing the economic models, non-randomised studies comparing ESG with LSG as well as studies reporting weight loss in the longer-term were identified from the evidence map. Indirect comparisons Seven RCTs were included in the indirect comparison, two RCTs comparing ESG with LSI, three RCTs comparing IGB with LSI and two RCTS comparing semaglutide with LSI. The analysis found little evidence of a difference in mean per cent of total body weight loss (95% confidence interval) between ESG and semaglutide at 6 months [2.15 (−29.47 to 33.76)] and 12 months [0.54 (−2.05 to 3.14)]. There was also little evidence of a difference between IGB and semaglutide at 6 months [0.37 (−6.25 to 6.98)] but good statistical evidence of a difference in favour of greater weight loss with semaglutide at 12 months [−7.91 (−11.14 to −4.67)]. Limitations of the analysis include some uncertainty around the transitivity assumptions made such as similarity of comparators and populations. A vast amount of research has been undertaken on a range of endoscopic therapies for obesity. The searchable evidence map provides a useful repository of evidence which can be used for planning and informing future research, including economic models. There were few economic evaluations of endoscopic therapies, and the models developed for this report will therefore add early evidence to the cost-effectiveness of endoscopic therapies. The three Markov models respectively found that over a 5-year time horizon, LSG was likely to be cost-effective compared with ESG (for obesity class II and III), and for obesity class I and II, ESG was likely to be cost-effective compared with semaglutide, and IGB was dominated by semaglutide. The model comparing ESG and LSG was robust to sensitivity analyses, while the other models were somewhat sensitive to intervention costs. There was substantial uncertainty around long-term weight loss for both semaglutide and IGB.

Authors' methods: Comprehensive searches were undertaken to January 2023 and a searchable evidence map of all quantitative studies (n > 2) on endoscopic treatments was constructed. The map was used where possible to inform the economic models. Indirect comparisons were undertaken where relevant direct evidence for the model was not available. A systematic review of cost-effectiveness studies was undertaken. Targeted searches were undertaken to identify additional evidence to inform model parameters. Three economic (Markov) models were designed to estimate the cost-effectiveness of endoscopic therapies compared to alternative weight management interventions from a United Kingdom National Health Service and Personal Social Services perspective. The effectiveness evidence base was greater and more wide-ranging than anticipated. However, for the interventions compared within the economic models, there were no randomised controlled trials and either limited, or an absence of, direct comparative evidence. There was also limited long-term data on interventions. These limitations necessitated the use of assumptions in modelling. The review was registered on PROSPERO (CRD42022302942) and reporting followed the general principles of the Preferred Reporting Items for Systematic Reviews and Meta Analyses. Evidence map Searches and study selection Databases [Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE and EMBASE] were searched from inception to January 2023. There were no restrictions by study design, language, date of publication or publication type. Two reviewers independently undertook title and abstract screening and full-text selection. Disagreements were resolved by a third reviewer or by consensus and reasons for exclusion were recorded.

Authors' identified further research: Future research should focus on longer-term studies evaluating effectiveness of endoscopic treatments, studies directly comparing endoscopic therapies against semaglutide and other emerging weight loss drugs, and studies which better reflect the complex treatment pathways of obesity. It could also explore the effectiveness of endoscopic therapies for patients in different obesity classes. Such studies could provide more robust evidence for informing future cost-effectiveness models beyond a 5-year time horizon.

Project Status: Completed

URL for project: https://www.journalslibrary.nihr.ac.uk/programmes/hta/NIHR133099

Year Published: 2025

URL for published report: https://www.journalslibrary.nihr.ac.uk/hta/PWKQ2310

URL for additional information: English

English language abstract: An English language summary is available

Publication Type: Full HTA

Country: England, United Kingdom

DOI: 10.3310/PWKQ2310

Organisation Name: NIHR Health Technology Assessment programme

Contact Address: NIHR Journals Library, National Institute for Health and Care Research, Evaluation, Trials and Studies Coordinating Centre, Alpha House, University of Southampton Science Park, Southampton SO16 7NS, UK

Contact Name: journals.library@nihr.ac.uk

Contact Email: journals.library@nihr.ac.uk