Gastric Bypass is a Cost-Saving Procedure: Results from a Comprehensive Markov Model

Obesity is a growing public health problem in industrialized countries and is directly and indirectly responsible for almost 10 % of all health expenditures. Bariatric surgery is the best available treatment, however, associated with important economical expenditures. So, cost-effectiveness analysis of the available surgical options is paramount. We developed a Markov model for three different strategies: best medical management, gastric band, and gastric bypass. The Markov model was constructed to allow for the evaluation of the impact of several obesity-related comorbidities. The results were derived for a representative population of morbidly obese patients, and subgroup analyses were performed for patients without comorbidities, patients with diabetes mellitus, different age, and body mass index (BMI) groups. Cost-effectiveness analysis was performed accounting for lifetime costs and from a societal perspective. Gastric bypass is a dominant strategy, rendering a significant decrease in lifetime costs and increase in quality-adjusted life years (QALYs). Comparing with the best medical management, in the global population of patients with a BMI of > 35 kg/m(2), gastric bypass renders 1.9 extra QALYs and saves on average 13,244a,not sign per patient. Younger patients, patients with a BMI between 40 and 50 kg/m(2), and patients without obesity-related diseases are the ones with a bigger benefit in terms of cost effectiveness. Gastric bypass surgery increases quality-adjusted survival and saves resources to health systems. As such, it can be an important process to control the ever-increasing health expenditure.