Identification of factors predicting low-risk febrile neutropenia admissions in adults with acute myeloid leukemia (AML)

Blood Adv. 2024 Oct 5:bloodadvances.2024014291. doi: 10.1182/bloodadvances.2024014291. Online ahead of print.

Abstract

Febrile neutropenia (FN) is the most common reason for hospital readmission following chemotherapy for AML and is a major driver of healthcare resource utilization. While FN risk models exist, these have largely been developed and validated in solid tumors. We therefore examined whether baseline characteristics could predict which AML patients with FN have a lower risk of progression to severe illness. We identified adults with high-grade myeloid neoplasm (³10% blasts in blood/marrow) who received intensive chemotherapy and were admitted for FN from 2016-2023. We collected baseline clinical and disease variables. Outcomes were: infections identified, hospital length of stay (LOS), intensive care unit (ICU) admission, and survival. A "lower-risk [LR]" outcome was defined as LOS <72hrs without ICU admission or inpatient death. Univariate and multivariable (MV) logistic regression models were used to assess covariate associations with outcomes. We identified 397 FN admissions in 248 patients (median age 61 [range: 29-77] years). The median hospital LOS was 6 (range: 1-56) days; 10% required ICU admission and 3.5% died inpatient. Only 15% of admissions were LR. Infection was identified in 59% of admissions. Physiologic parameters including heart rate, blood pressure and fever height were the best predictors of LR admission and infection. We developed MV models to predict LR admission and infection with AUCs of 0.82 and AUC 0.72, respectively. Established FN and critical illness models were not predictive of outcomes in AML, where we could not identify a lower risk group; thus an AML-specific FN risk model requires further development and validation.