OBJECTIVES: The economic impact of relapse post-HSCT has not been evaluated in AML. A claims-based study was performed to assess healthcare resource utilization (HRU) and costs in patients with AML following HSCT in the US.

METHODS: In this retrospective (2012-2017) study, IBM MarketScan^® databases were used to identify adult patients with newly diagnosed AML who underwent HSCT. Relapse was identified using ICD-9/10 codes. Relapsed and relapse-free cohorts were matched for baseline demographic/disease characteristics. Multivariate regression analyses were adjusted for baseline imbalances between the two cohorts; costs were estimated in 2017 USD.

RESULTS: 620 patients (n=310 each in relapsed and relapse-free cohorts) were eligible for inclusion (mean age, 54 years; average of 5 months from AML diagnosis to HSCT). The relapsed cohort had more all-cause inpatient admissions (0.21 vs 0.06 events/person-month [PM]; adjusted incidence rate ratio [IRR]=4.58), outpatient visits (5.49 vs 3.78 events/PM; IRR=1.51), emergency department (ED) visits (0.22 vs 0.09 events/PM; IRR=2.58), and longer hospital stays (3.27 vs 0.67 days/PM; IRR=5.00) than the relapse-free cohort. The relapsed cohort had more AML-related inpatient admissions (0.20 vs 0.03 events/PM; IRR=7.41), longer hospital stays (3.18 vs 0.44 days/PM; IRR=7.31), more outpatient visits (3.79 vs 1.27 events/PM; IRR=3.06), more ED visits (0.12 vs 0.01 events/PM; IRR=9.11), and more blood transfusions (0.50 vs 0.07 events/PM; IRR=5.38). Monthly mean healthcare costs were significantly higher in the relapsed versus the relapse-free cohort. Cost differences for all-cause total medical costs, inpatient admissions, outpatient visits, and ED visits were $45,412, $37,202, $7,772, and $438, respectively (all P<0.001). The relapsed cohort also incurred higher medical costs related to chemotherapy (cost difference: $9,960/month), graft-versus-host disease ($5,141/month), blood transfusion ($1,786/month), and bone marrow biopsy ($2,108/month) (all P<0.05).

CONCLUSIONS: Significantly increased HRU and healthcare costs associated with relapse post-HSCT highlight the tremendous unmet need for new treatments that reduce post-HSCT relapse risk.