Economics and Policy in Bariatric Surgery

Bariatric and metabolic surgery in patients with low body mass index: an online survey of 543 bariatric and metabolic surgeons

BACKGROUND

Metabolic and bariatric surgery (MBS) in patients with low body mass index patients is a topic of debate. This study aimed to address all aspects of controversies in these patients by using a worldwide survey.

METHODS

An online 35-item questionnaire survey based on existing controversies surrounding MBS in class 1 obesity was created by 17 bariatric surgeons from 10 different countries. Responses were collected and analysed by authors.

RESULTS

A total of 543 bariatric surgeons from 65 countries participated in this survey. 52.29% of participants agreed with the statement that MBS should be offered to class-1 obese patients without any obesity related comorbidities. Most of the respondents (68.43%) believed that MBS surgery should not be offered to patients under the age of 18 with class I obesity. 81.01% of respondents agreed with the statement that surgical interventions should be considered after failure of non-surgical treatments.

CONCLUSION

This survey demonstrated worldwide variations in metabolic/bariatric surgery in patients with class 1 obesity. Precise analysis of these results is useful for identifying different aspects for future research and consensus building.

Estimated Cost-effectiveness of Medical Therapy, Sleeve Gastrectomy, and Gastric Bypass in Patients With Severe Obesity and Type 2 Diabetes

Importance

Bariatric surgery is recommended for patients with severe obesity (body mass index ≥40) and type 2 diabetes (T2D). However, the most cost-effective treatment remains unclear and may depend on the patient's T2D severity.

Objective

To estimate the cost-effectiveness of medical therapy, sleeve gastrectomy (SG), and Roux-en-Y gastric bypass (RYGB) among patients with severe obesity and T2D, stratified by T2D severity.

Design, Setting, and Participants

This economic evaluation used a microsimulation model to project health and cost outcomes of medical therapy, SG, and RYGB over 5 years. Time horizons varied between 10 and 30 years in sensitivity analyses. Model inputs were derived from clinical trials, large cohort studies, national databases, and published literature. Probabilistic sampling of model inputs accounted for parameter uncertainty. Estimates of US adults with severe obesity and T2D were derived from the National Health and Nutrition Examination Survey. Data analysis was performed from January 2020 to August 2021.

Exposures

Medical therapy, SG, and RYGB.

Main Outcomes and Measures

Quality-adjusted life-years (QALYs), costs (in 2020 US dollars), and incremental cost-effectiveness ratios (ICERs) were projected, with future cost and QALYs discounted 3.0% annually. A strategy was deemed cost-effective if the ICER was less than $100 000 per QALY. The preferred strategy resulted in the greatest number of QALYs gained while being cost-effective.

Results

The model simulated 1000 cohorts of 10 000 patients, of whom 16% had mild T2D, 56% had moderate T2D, and 28% had severe T2D at baseline. The mean age of simulated patients was 54.6 years (95% CI, 54.2-55.0 years), 61.6% (95% CI, 60.1%-63.4%) were female, and 65.1% (95% CI, 63.6%-66.7%) were non-Hispanic White. Compared with medical therapy over 5 years, RYGB was associated with the most QALYs gained in the overall population (mean, 0.44 QALY; 95% CI, 0.21-0.86 QALY) and when stratified by baseline T2D severity: mild (mean, 0.59 QALY; 95% CI, 0.35-0.98 QALY), moderate (mean, 0.50 QALY; 95% CI, 0.25-0.88 QALY), and severe (mean, 0.30 QALY; 95% CI, 0.07-0.79 QALY). RYGB was the preferred strategy in the overall population (ICER, $46 877 per QALY; 83.0% probability preferred) and when stratified by baseline T2D severity: mild (ICER, $36 479 per QALY; 73.7% probability preferred), moderate (ICER, $37 056 per QALY; 85.6% probability preferred), and severe (ICER, $98 940 per QALY; 40.2% probability preferred). The cost-effectiveness of RYGB improved over a longer time horizon.

Conclusions and Relevance

These findings suggest that the effectiveness and cost-effectiveness of bariatric surgery vary by baseline severity of T2D. Over a 5-year time horizon, RYGB is projected to be the preferred treatment strategy for patients with severe obesity regardless of baseline T2D severity.