Usefulness of Charlson Comorbidity Index to Predict Early Mortality and Overall Survival in Older Patients With Acute Myeloid Leukemia

Abstract

Introduction: Older adults with acute myeloid leukemia (AML) often have significant comorbidities. We hypothesized that greater comorbidity burden predicts worse 1-month mortality and overall survival (OS) in patients ≥60 years with AML.

Materials and methods: We included 50,668 patients ≥60 years diagnosed between 2004 and 2014 from the National Cancer Database; patients were divided into 3 groups with Charlson comorbidity index (CCI) 0, 1, and ≥2. Chi-square tests were used to examine the association between CCI and different variables. We used logistic regression and Cox proportional hazard models to determine predictors of 1-month mortality and OS, respectively.

Results: Among the entire cohort, 65% had CCI 0, 24% had CCI 1, and 11% had CCI ≥2. Thirty-four percent did not receive chemotherapy. Patients with CCI 0 were more likely to receive chemotherapy, especially multiagent chemotherapy and undergo upfront hematopoietic cell transplantation. In multivariate analyses, 1-month mortality and OS were significantly worse with CCI 1 or ≥2, compared with CCI 0 in the entire cohort, as the subgroup of only those patients who received chemotherapy. Younger age, male gender, higher annual income, academic facility, longer travel distance, and acute promyelocytic leukemia were associated with improved OS.

Conclusion: In one of the largest real-world studies of older adults with AML, we demonstrated that greater comorbidity, measured by higher CCI, independently predicted worse early mortality and OS in older patients with AML. Higher CCI was more common with increasing age and correlated with lower likelihood of receiving chemotherapy and hematopoietic cell transplantation. Whether optimal comorbidity management and supportive care may improve outcomes needs to be studied further.

Keywords: Acute leukemia; Chemotherapy; Geriatrics; Older adults; Survival.