Cost-effectiveness analysis of bariatric surgery and pharmacological treatment methods in the treatment of obese patients with Type 2 diabetes

ABSTRACT Diabetes and obesity are a huge global health threat that poses increasing challenges to public health and health systems worldwide. The aim of this study is to determine the cost-effectiveness of Sleeve Gastrectomy (SG) and Pharmacological Therapy (PT) methods, which are among the types of Bariatric Surgery (BC) in obese patients with Type 2 Diabetes Mellitus (T2DM), from the perspective of the reimbursement institution and to perform budget impact analysis of these treatments. The population of the study consisted of 44 obese patients with T2DM receiving SG treatment at Balıkesir University Health Practice and Research Hospital and 55 patients receiving FT treatment at Süleyman Demirel University Health Practice and Research Hospital. No sample was selected in the study and the entire population was included in the study. The costs of FT and SG treatments in obese patients with T2DM were calculated from the perspective of the reimbursement institution and according to the Public Health Service Price Tariff (PHSPT) in order to determine the costs of patients who will apply within the scope of health tourism. Cost data were obtained from the patient treatment invoices of hospitals and effectiveness values were obtained from the literature through systematic review. In the study, Markov model was used to determine the cost-effectiveness of alternative treatment options. In the model, the cycle length was determined as 1 year and the time period as lifetime (60 years). In the study, the mortality rates included in the transition probabilities of the Markov model were used as Turkey-specific age-related mortality rates and the model was revised for Turkey. In the study, the cost of alternative treatment options and quality-adjusted life years (QALY) of obese patients with T2DM were calculated and 3% was applied as a reduction rate. Additional cost-effectiveness ratio (ICER) and additional net monetary benefit (NMB) were used as outcome measures. As a result of the cost-effectiveness analysis, one-way and probabilistic sensitivity analyses were performed. In the study, according to Health Practices Communique (HPC), PT costs for remission status were determined as 19,551.25 ₺ for the first and second year and 1,368.12 ₺ for the third year and beyond. SG costs are 38,980.51 ₺ for the first year and 1,551.12 ₺ for the second year and beyond.In the case of T2DM, PT costs are the same with the remission status for the first and second years, while it is 3,596.15 ₺ for the third year and beyond. The annual cost of SG calculated for the first year is the same with the remission status. The annual cost of SG for the second year and beyond was calculated as 3,738.63 ₺. As a result of the Markov model, the total lifetime costs of PT and SG were determined as 95,578.974 ₺ and 113,245.46 ₺, respectively.Lifetime clinical effectiveness values of PT and SG were determined as 11.33 and 12.68, respectively. As a result of the cost-effectiveness analysis performed among alternative treatment methods in obese patients with T2DM, SG brings 1.34 additional effectiveness and 17.666,481 ₺ additional cost compared to PT. The threshold value (WTP) was calculated as 923,856 ₺. As a result of the study, SG was found to be a cost-effective treatment method that provides cost savings compared to PT in the treatment of obese patients with T2DM.In the budget impact analysis, it was estimated that 0.78% of the total health expenditure in 2023 was spent for the treatment of obese patients with T2DM with PT and SG methods from the perspective of the reimbursement institution. As a result, bariatric surgery was found to be a cost-effective treatment option in highly obese patients with T2DM over a 60-year period. However, each obesity treatment method is a life-saving intervention. Therefore, treatment programmes consisting of a combination of different obesity treatment methods should be planned and implemented for patients. The methods used in the treatment of obesity should be considered as complementary treatment methods rather than competitive in health service provision. In order to prevent the disease, it is recommended to invest in the control of obesity and diabetes by applying the necessary diagnosis and treatment methods and to develop health policies to reduce early mortality rates.