Real-World Assessment of Nationwide Health Economic Burden and Treatment-Based Survival for Current Myelodysplastic Syndromes Treatment Practice in Japan

Introduction: Myelodysplastic syndromes (MDS) are a group of progressive clonal hematopoietic malignancies that primarily affect an elderly demographic. MDS is treated based on age, symptoms, disease severity, and prognostic scoring. There is limited evidence on the health economic burden and how transfusion dependency affects clinical outcomes of patients with MDS in Japan. This is the first retrospective database analysis study that was performed to elucidate the patient baseline characteristics, 1-year medical costs, and 3-year overall survival (OS) in patients treated for MDS using an administrative claims database of more than 150 hospitals in Japan.

Methods: In this study, we used the Medical Data Vision (MDV) database to identify patients diagnosed with MDS (International Classification of Diseases, Tenth Revision, [ICD-10]: code D46.9) using a nationwide administrative database comprising anonymized data covering more than 25 million patients. Patients who received transfusions, erythropoiesis-stimulating agents (ESA) with or without transfusions, azacitidine (AZA) with or without transfusions, and other (e.g. chemotherapy such as doxorubicin, cytarabine) as the index treatment during the identification period from October 1, 2009 to June 30, 2018 were included if they had 1 year of lookback data before the index date and a follow-up period of ≥ 1 year.

Results: Of the 5,981 patients with MDS who met the eligibility criteria for this study, 37.8% were female; the median age of patients was > 70 years. Patients receiving transfusion in their index line of therapy was the largest regimen group (n = 2,844, 47.6%), followed by AZA + transfusion (n = 703, 11.8%), ESA (n = 294, 4.9%), and AZA (n = 288, 4.8%). The AZA regimen had the youngest mean age of 70.2 years while the ESA + transfusion group had the oldest (77.8 years). AZA and AZA + transfusion groups recorded a median Charlson Comorbidity Index score of 1.9 and 2.0, respectively, whereas ESA and ESA + transfusion groups had a mean score of 3.2 and 2.6, respectively. Medical costs varied widely for these groups (Figure 1). Mean overall costs were highest for the AZA + transfusion regimen group (USD 63,226) and lowest for the ESA group (USD 15,931). Mean overall costs for regimen groups without transfusion were highest for AZA (USD 47,475), followed by ESA (USD 15,931; P < 0.0001), and the addition of the transfusion component was observed to incur higher overall costs, inpatient costs, and MDS-related treatment costs. Inpatient costs for the ESA groups ranged from USD 16,717 for ESA only to USD 30,347 for ESA + transfusion. The highest outpatient costs were observed for the AZA group (USD 20,011; P < 0.0001). MDS-related treatment costs were highest for the AZA + transfusion group (USD 32,123) and lowest for the ESA group (USD 2,518; P < 0.0001). Overall, there were 1,966 deaths (32.9%) recorded within 3 years of index treatment. The median OS for patients receiving AZA + transfusion was 957 days (Figure 2).

Conclusions: In this study, mean overall costs, inpatient costs, and outpatient costs were highest for the AZA + transfusion regimen group. Consistent with the trend of MDS studies, the majority of patients with MDS received supportive transfusion-dependent therapy. Transfusion dependency led to considerable incremental cost and poorer clinical outcomes compared with other regimens. This study provides insights into the real-world disease burden for patients with MDS and the current treatment options available for MDS in Japan.