Research In Practice Blog
Intro
Survival outcomes for children with acute myeloid leukemia (AML) are lower for Hispanic and non-Hispanic Black children compared to non-Hispanic White children, analysis of national data. Findings from a new study led by researchers from Clinical Futures and Children’s Hospital of Philadelphia, suggests that high cardiovascular and respiratory acuity at cancer diagnosis are contributing factors to disparities in overall survival for Hispanic and non-Hispanic Black children.
“If we want to eliminate these disparities, we have to look beyond the cancer itself and really understand what’s happening across the entire care continuum, including before a child even reaches the cancer center,” Daniel Zheng, MD, MHS, MSHP, lead author on the study, said in an article written by Healio.
Study Design and Methods
In this retrospective cohort study, researchers, including Daniel Zheng, MD, MHS, MSHP, Caitlin Elgarten, MD, MSCE, Brian T. Fisher, DO, MSCE, MPH, Regina Myers, MD, Alix E. Seif, MD, MPH, Richard Aplenc, MD, PhD, MSCE, and Kelly D. Getz, PhD, MPH analyzed data from the Real-World Epidemiology of Acute Leukemia-AML (REAL-AML) cohort. A total of 773 children treated for AML from January 2011 through May 2024 at 13 US children’s hospitals across 10 states were included in this study. The race/ethnicity breakdown of the cohort was as follows: 125 (16.2%) were Black, 237 (30.7%) were Hispanic and 411 (53.2%) were White. The primary outcome was overall survival (OS), defined as the time from initial AML diagnosis until death from any cause. Three potential mediators were examined for this analysis:
- Presentation acuity was defined as documented use of organ system-specific intensive care unit (ICU)-level requirements during the first three days of the index hospital admission for an initial AML diagnosis. Evaluated organ systems included cardiovascular, respiratory, renal, neurologic, and apheresis-related support.
- Severe organ toxic effects during frontline chemotherapy were defined as the use of cardiovascular, respiratory, renal, and neurologic ICU-level resources during frontline AML treatment.
- AML relapse was defined as the reappearance of leukemic blasts (5% or greater) in the bone marrow, peripheral blood, or extramedullary sites following a prior complete remission.
Findings
Black and Hispanic children had worse overall survival compared with White children. The unadjusted 5-year OS for White patients was 70.0% compared with 61.1% for Black and 65.4% for Hispanic patients. Both Black and Hispanic patients had an increased hazard of death compared with White patients. Black children experienced over 50% and Hispanic children experienced over 30% increased hazard of death.
The overall survival disparity for Black patients was partially explained by differences in cardiovascular and respiratory acuity at presentation (14% and 8%, respectively). Compared with White patients, Black patients had increased risk of higher cardiovascular and respiratory acuity at presentation. Presentation acuities were largely comparable between Hispanic and White patients.
Findings suggested no significant increases in frontline organ toxic effects or relapse rates by race and ethnicity. Compared with White patients, Black and Hispanic patients at initial AML diagnosis were more likely to be publicly insured and less likely to be enrolled in a frontline clinical trial for treatment.
Clinical Implications
"Our results suggest that the long-term potential impact of cardiovascular and respiratory acuity at presentation is associated with meaningful differences in overall survival by race and ethnicity,” said Dr. Zheng.
Cardiovascular and respiratory acuity at presentation partially mediated the overall survival difference between Black and White children. These findings suggest that some children, disproportionately Black children, may be reaching specialty care with greater illness severity. The authors highlighted the need to examine barriers in health care access as illness severity may represent delays in diagnosis. One relevant policy consideration is the ability to maintain continuous insurance coverage. Previous research suggests that continuous Medicaid coverage is associated with improved survival benefits in children, adolescents, and young adults with cancer.
The findings demonstrate that survival disparities in pediatric AML persist despite similar relapse rates across groups suggesting that factors beyond disease recurrence drive disparities. Among Black children, greater cardiovascular and respiratory illness severity at diagnosis appear to contribute to poorer outcomes, although much of the survival disparity remains unexplained. For clinicians, this study underscores the importance of equitable access to timely diagnosis, comprehensive supportive care, and continued efforts to address social determinants of health and healthcare system factors that affect children with cancer and their families.
Clinical Futures author(s): Daniel J Zheng, Caitlin W Elgarten, Brian T Fisher, Regina M Myers, Alix E Seif. Richard Aplenc, and Kelly D Getz