Healthcare Resource Utilization, Treatment Costs, and Mortality in Patients with Malignancies or Transplantation Who Develop Invasive Aspergillosis.

: Invasive aspergillosis (IA) poses significant risks to patients with malignancies or transplantation; however, estimates of burden-of-illness in patients with IA are sparse. We sought to assess in-hospital and outpatient healthcare resource utilization, all-cause treatment costs, and mortality in patients admitted with IA with hematologic or non-hematologic malignancies, bone marrow transplant/hematopoietic cell transplantation (BMT/HCT), or solid organ transplantation (SOT). : This claims study utilized United States IQVIA data. Adults admitted for IA were identified by diagnosis codes during the patient selection period (October 2015-November 2022). IA patients were stratified into cohorts including recent hematologic or non-hematologic malignancies, or a history of BMT/HCT or SOT. We assessed hospital and intensive care unit (ICU) length-of-stay (LOS), all-cause index hospital treatment costs, and inpatient mortality or need for hospice in each cohort, as well as the need for re-admission and total treatment costs for up to six-months after admission, and all-cause mortality at end of study follow-up. : Among 1190 patients admitted for IA, 317 had hematologic malignancies, 155 non-hematologic malignancies, 133 BMT/HCT and 173 SOT. Across these cohorts, IA was associated with protracted (median LOS = 12-18 days; ICU LOS = 10-13 days) and costly (median = USD 79,058-USD 172,342) index hospitalizations ending in death or hospice in 28.1% (89/317) to 36.1% (48/133) of patients. Among those surviving to discharge, between 53.1% (34/64) and 63.4% (97/153) were re-admitted within six months. Total median treatment costs at six months ranged from USD 213,378 to USD 397,857. All-cause mortality was 33.6% (52/155) to 40.6% (54/133) at end of study follow-up. : Hospitalizations for IA in patients with malignancies or transplantation are long, costly, and end with readmission, hospice, or death in more than one-third of patients.