Cost-Effectiveness of Bariatric Surgery Compared to Conventional Treatment From A Societal Perspective In Germany, France, Italy And The UK

Abstract

Obesity and diabetes are growing epidemics in European countries. Bariatric surgery is recommended for the treatment of patients with moderate or morbid obesity, particularly in patients who also have type 2 diabetes mellitus (T2DM). The objective was to investigate the cost-effectiveness of bariatric surgery in patients with morbid obesity or moderate obesity with obesity-related comorbidities; T2DM patients with BMI≥35; T2DM patients with BMI≥30,<35; and all patients with mild obesity, from the societal perspective in Germany, France, Italy and the UK. A Markov model with a cohort of 1,000 patients was used to evaluate the cost-effectiveness of bariatric surgery compared to conventional treatment (CT) over a 20-year time horizon. Model inputs from the literature informed the complex nature of obesity and its associated comorbidities, including T2DM, stroke, myocardial infarction, cancer, knee pain and obstructive sleep apnoea. Up-to-date healthcare costs from the four countries were applied. Productivity loss calculations were included to account for differences in employment rates and overall work impairment between bariatric surgery and CT. In the T2DM population with BMI≥35, 47%/14% of patients were in T2DM remission at year 10/20 following bariatric surgery, compared to 10%/4% of patients treated with CT. In the morbidly obese population, the cumulative number of patient-years with T2DM was 46-57% lower and there were 32-42% fewer new T2DM cases with bariatric surgery compared to CT over 20 years. Bariatric surgery dominated CT from the societal perspective in all countries and populations, except in the UK T2DM population with BMI≥30,<35, where the ICER was £559/QALY. Probabilistic sensitivity analyses showed the model results to be robust to uncertainty. Bariatric surgery is highly cost-effective in Germany, France, Italy and the UK. Full implementation of existing clinical guidelines would reduce the burden of obesity and T2DM and generate economic benefits for society.