Dr. Jennifer Kaplan Wins John Halverson Young Investigator Award from ASMBS During ObesityWeek
The Benefit and Cost Effectiveness of Laparoscopic Gastric Bypass Stems Largely From Resolution of Metabolic Disease, Not Just Obesity Resolution
Bariatric surgery has demonstrated cost-effectiveness when compared to non-operative weight loss interventions, but these analyses focus on body weight as bariatric surgery’s main influence on mortality. The Edmonton Obesity Staging System (EOSS) incorporates metabolic disease into obesity severity, and predicts mortality better than body mass index alone. We constructed a Markov model based on the EOSS to determine the cost-effectiveness of laparoscopic gastric bypass (LGB) as compared to medical management. The model incorporates bariatric surgery’s effect on both obesity and metabolic disease.
Patients began in a decision tree with two strategies: laparoscopic gastric bypass or medical management of obesity. After the first two years postoperatively, patients transitioned to a Markov model to evaluate the impact of surgery or medical management on a patient’s EOSS stage over their lifetime. Base case scenarios, 30-day mortality, and complications were determined from the National Surgical Quality Improvement Program (NSQIP) dataset between 2011-2013, and additional inputs taken from current literature. Incremental cost-effectiveness ratios (ICERs) were calculated for men and women as direct medical cost per quality-adjusted life-year (QALY) gained. Sensitivity analyses for BMI, age, weight loss, and comorbidity resolution were performed. Model inputs were taken from the literature.
As compared to medical management, gastric bypass resulted in increased QALYs and decreased cost. There was a QALY gain of 2.68 and cost savings of $50,662 starting at 11 years postoperatively (3% discount rate for cost and QALYs). For the base case of a 45-year-old woman with a BMI of 45kg/m2, three life years were gained with LRYGB. In sensitivity analyses, the ICER was most affected by surgical and follow-up costs.
LRYGB is a cost-saving treatment for the management of obesity, largely through its effect on the resolution of metabolic disease. It results in improved life-span, quality-adjusted survival, and cost-savings.