Economic Impact of Transformation to Acute Myeloid Leukemia Among Actively Managed Patients with Higher-Risk Myelodysplastic Syndromes in the United States

Introduction: Transformation of higher-risk myelodysplastic syndromes (MDS) to acute myeloid leukemia (AML) may be associated with increased healthcare resource utilization (HCRU) and costs. To describe this economic impact, HCRU and costs were compared between US patients who experienced transformation to AML and those who did not. Methods: Using the Optum administrative claims data, this retrospective matched cohort study identified patients (>= 18 years old) with higher-risk MDS who initiated first-line therapy between January 1, 2008, and June 30, 2019. Patients whose disease transformed to AML were matched 1:1 to patients whose disease did not transform, based on the duration of followup. The follow-up period was divided into two periods: pre- (before transformation to AML) and post-AML (after transformation to AML). For patients who did not transform to AML, preand post-AML periods were determined using the transformation date of their matched pair. HCRU and total adjusted costs (2019 US dollars, $) were compared between patients who transformed to AML and those who did not. Results: A total of 118 matched patient pairs were included in the study. The hospitalization rate was significantly higher in patients who transformed than in those who did not during the entire follow-up (58.8% vs. 44.1%; P = 0.0295) and post-AML (47.5% vs. 28.0%; P = 0.0028) periods. Across all periods, supportive care use was significantly higher among patients who transformed to AML vs. patients who did not transform. Adjusted mean monthly costs for patients with higher-risk MDS who transformed to AML were higher than those who did not transform ($25,964 vs. $19,150; P < 0.0001). The observed total cost difference was more notable in the post-AML period ($36,424 vs. $14,860; P < 0.0001). Conclusions: Patients with higher-risk MDS whose disease transformed to AML incurred significantly higher healthcare costs compared to those whose disease did not transform, highlighting the important need for treatments that prevent or delay transformation.