Real-world treatment patterns and outcomes of patients with LR-MDS in Japan: an electronic health record database study

Real-world treatment patterns and clinical outcomes for patients with lower-risk myelodysplastic syndromes (LR-MDS) in Japan are insufficiently characterized. This study assessed treatment patterns, clinical outcomes, costs, and healthcare resource utilization of patients with LR-MDS in Japan using the AsMedix electronic health record database. The study included 177 patients aged ≥ 18 years with LR-MDS, identified between April 1, 2017, and March 31, 2022. Of these, 79 were transfusion dependent (TD) and 98 were non-transfusion dependent (NTD). Treatment patterns were diverse, and 57 (32.2%) patients received hypomethylating agents (combination or monotherapy) as first-line treatment. Median (95% confidence interval) overall survival was 32.6 months (17.6-not evaluable) among TD patients who achieved red blood cell transfusion independence (RBC-TI) ≥ 8 weeks during weeks 1-24, compared with 22.3 months (10.1-not evaluable) among those who did not (P = 0.17). Among NTD patients, maintaining NTD status was also associated with longer median overall survival. Furthermore, patients who achieved or maintained RBC-TI incurred roughly half the monthly medical costs per individual compared with those who did not, highlighting the clinical and economic importance of reducing RBC transfusion requirements. Further research is needed to understand the impacts of treatment on patients with LR-MDS-related anemia in Japan.