PSU22 LONG TERM COST EFFECTIVENESS OF BARIATRIC SURGERY COMPARED TO DIET IN ITALY: PRELIMINARY RESULTS

Abstract

The aim of the study was to evaluate the cost-effectiveness of bariatric surgery (BS) in Italy, stressing the lifetime financial impact of BS compared to diet combined with physical exercise. The Markov model for budget impact analysis of BS in Italy was extended to include the quantification of patients’ quality of life, out-of-pocket (OOP) costs and productivity losses. The model considered the following populations: (i) BMI >= 40 without complications + BMI >= 35 with complications; (ii) BMI >= 35 and diabetes; (iii) BMI=30-35 and diabetes. Baseline utilities and disutility values for the different health states considered in the model were obtained using publicly available sources. OOP costs and productivity losses were estimated from the literature and previous longitudinal multicenter survey in Italy. A societal perspective and a lifetime horizon (40 years) were considered. Cost-effectiveness was assessed using the incremental net monetary benefit (NMB) approach. Health benefits were converted into the common monetary metric using willingness to pay threshold. BS resulted in significantly reduced OOP and productivity losses, the savings can be noted from the first year after surgery. Over a lifetime horizon, BS generated a higher number of quality-adjusted life years than diet combined with exercise. The overall incremental NMB of BS was positive in all populations concerned. Despite the initial investment, the incremental NMB for BS became positive between two and four years after surgery. In a lifetime horizon BS was cost-saving from a societal perspective and resulted in better health outcomes for patients.