Cost-effectiveness analysis of pharmacotherapy and deep brain stimulation treatment in parkinson's disease

Parkinson's disease (PD) is one of the most common neurodegenerative disorders. In addition to pharmacological treatment, Deep Brain Stimulation (DBS) has become an alternative treatment option for advanced Parkinson's disease. The aim of this study was to analyze the cost-effectiveness of DBS combined with medical treatment compared to medical treatment alone. Since the reimbursement agency perspective was adopted in the study, direct medical costs were calculated. The bottom-up costing method was used to determine the costs of treatment options. Clinical effectiveness values were obtained from the literature by systematic review. Data on side effects of the disease were obtained from clinical studies, published reports or meta-analyses. Markov model was used to determine the cost-effectiveness of alternative treatment options in the study. Cycle length was determined as 6 months and time period as 15 years in the model. Hoehn and Yahr (H&Y) 'on-off' conditions were used to adapt the natural course of the disease to the Markov model. In the study, the cost of alternative treatment options and quality-adjusted life years (QALY) of patients with PD were calculated. A discount rate of 3% was applied. In addition, ıncremental cost effectiveness ratio (ICER) and ıncremental net monetary benefit (INMB) values were used as outcome measures. The cost-effectiveness analysis result was calculated for 1, 5, 10 and 15 years and one-way and probabilistic sensitivity analysis were performed. In this study, the total costs according to the Markov model in the 15-year period were determined as 100,573.96 TL (3,302.30 $) for pharmacotherapy alone and 563,924.94 TL (18,516.23 $) for pharmacotherapy with DBS. The clinical effectiveness values in the 15-year period were found to be 1.93 for pharmacotherapy alone and 3.61 for pharmacotherapy combined with DBS. As a result of the cost-effectiveness analysis, it was determined that DBS treatment had an ıncremental effectiveness of 1.68 compared to pharmacotherapy and an ıncremental cost of 463,350.97 TL (14,111.67 $). As a result of the research, DBS treatment is not cost-effective in the short term (1-5 years) compared to pharmacotherapy due to the high cost in the first year of the surgery. In the long term (10-15 years), it was found to be cost-effective due to the increase in health benefits and the decrease in costs. In sensitivity analyses, it was determined that the most effective parameters on cost-effectiveness were the costs of DBS and discount rate. In addition, the IMEO of DBS per QALY compared to pharmacotherapy was found to be 275,804.15 TL (9,032.4 $), thus determining DBS as the most cost-effective option. According to the budget impact analysis, it was determined that 1.42% of total health expenditures were spent on the treatment of PD. DBS has been found to be cost-effective in the long term compared to standard care from a reimbursement perspective in the treatment of advanced PD in the Turkish healthcare system. However, since the progression of PD varies depending on the characteristics of the patients, the quality of informal care and the severity of the disease, treatment programs consisting of a combination of different PD treatments should be planned and implemented. Therefore, when comparing the cost-effectiveness of these treatment methods, it is recommended that both treatment options be evaluated as complementary treatment methods rather than competitive.