Central nervous system involvement in acute myeloid leukemia: A national analysis of inpatient outcomes using the 2022 national inpatient sample

Abstract

Abstract Background: Central nervous system (CNS) involvement in acute myeloid leukemia (AML) is rare but portends worse outcomes. However, population-based estimates and predictors of CNS involvement and its impact on inpatient outcomes remain poorly characterized in the United States. Methods We conducted a retrospective cross-sectional study using the 2022 National Inpatient Sample (NIS). Adult inpatient admissions with AML were identified using ICD-10 diagnosis codes. CNS involvement was defined by secondary CNS neoplasm codes or lumbar puncture procedure codes. Survey-weighted regression models were used to assess predictors and outcomes, adjusting for demographics, payer, income, and hospital factors. Results Among an estimated 104,510 weighted AML hospitalizations in 2022, 3.16% had CNS involvement. Prevalence varied by region: West (4.12%, 95% CI 3.18-5.08), Northeast (3.74%, 95% CI 3.11-4.37), Midwest (2.77%, 95% CI 2.22-3.32), and South (2.57%, 95% CI 2.22-2.98). CNS involvement was inversely associated with age (AOR per year 0.97, 95% CI 0.97-0.98, p<0.001). Compared to White patients, Black (AOR 0.86), Hispanic (AOR 0.89), and other races (AOR 1.17) had no statistically significant differences in CNS involvement. Medicaid (AOR 1.25, 95% CI 1.00-1.56, p=0.047) was associated with higher odds compared to Medicare. CNS involvement was associated with significantly higher odds of In-hospital mortality (AOR 1.69, 95% CI 1.29-2.20, p<0.001), ICU-level care (AOR 2.12, 95% CI 1.63-2.77, p<0.001), longer length of stay (LOS Ratio 1.92, 95% CI 1.76-2.10, p<0.001), and higher hospitalization charges (Charge Ratio 2.10, 95% CI 1.87-2.37, p<0.001). Conclusions CNS involvement occurs in approximately 3% of AML hospitalizations and is associated with nearly double the inpatient mortality, ICU-level interventions, hospital stay, and cost. These findings warrant clinical vigilance and early multidisciplinary support - medical, financial, social - in AML patients with CNS involvement.