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Updated: May 14, 2026

Roux-en-Y Gastric Bypass Operation in Rats
Published on: June 11, 2012
Gastric bypass is a cost-saving procedure: results from a comprehensive Markov model
Gil R Faria1, John R Preto, José Costa-Maia
1Department of Surgery, Faculty of Medicine, University of Porto, Porto, Portugal. gilrfaria@gmail.com
Background:
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.
Methods:
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.
Results:
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/m2, gastric bypass renders 1.9 extra QALYs and saves on average 13,244€ per patient. Younger patients, patients with a BMI between 40 and 50 kg/m2, and patients without obesity-related diseases are the ones with a bigger benefit in terms of cost effectiveness.
Conclusions:
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.

