Studies show that non-Hispanic Black and Hispanic patients with acute myeloid leukemia (AML) have higher mortality rates than non-Hispanic White patients diagnosed with the disease, despite lower rates of incidence, more favorable genetics, and a younger age at disease onset. A study by Abraham et al presented at a press briefing in advance of the 2020 American Society of Hematology (ASH) Annual Meeting & Exposition (Abstract 217) investigated how structural violence—specifically, neighborhood socioeconomic status—contributes to racial/ethnic differences in the survival of patients with acute myeloid leukemia (AML). Researchers found that neighborhood socioeconomic status accounted for 37% and 50% of the racial disparity in death from leukemia and all causes, respectively.

Study Methodology

The researchers analyzed census tract data on 822 non-Hispanic White (n = 497), non-Hispanic Black (n = 126), Hispanic (n = 117), and other (n = 82) adult patients diagnosed with AML between 2012 and 2018 at six academic cancer centers in Chicago. The data were collected using the FFIEC Geocoding/Mapping System, and computed tract disadvantage and tract affluence scores were then categorized into distribution tertiles (low, moderate, and high). Time to relapse and death from leukemia were examined, adjusting for age, sex, and race/ethnicity (baseline models), and for potential mediators of racial disparities, including distal (Charlson Comorbidity Index [CCI], obesity, concentrated disadvantage and affluence, health insurance status), and proximal mediators (somatic mutations and European LeukemiaNet [ELN] prognostic score categories).

Results

The researchers found significant heterogeneity in patients’ age and comorbidities at diagnosis, with Hispanic patients being the youngest and having the lowest CCI scores. Morbid obesity was more prevalent in non-Hispanic Black and Hispanic patients: 23% and 20%, respectively, compared with 11% of non-Hispanic White patients. Payer source also differed significantly, with private insurance being twice as frequent among non-Hispanic White patients than non-Hispanic Black patients (51% vs 25%). The largest uninsured population was Hispanic.

According to the European LeukemiaNet prognostic score, adverse risk disease was most prevalent in non-Hispanic White patients. NPM1 gene mutations were least prevalent in Hispanic patients, and p53 mutations were more prevalent in non-Hispanic Black patients (26%) compared with non-Hispanic White patients (12%) and Hispanic patients (9%); although, due to the low numbers, this was not a significant difference (P = .10).

The researchers also found that non-Hispanic Black patients and Hispanic patients resided in more disadvantaged and less affluent areas than non-Hispanic White patients. Treatment data were available for 764 patients; 75% of patients received intensive induction therapy, and choice of first-line treatment did not differ by race or tract disadvantage. However, allogeneic transplant rates did differ by race, age, insurance status, tract disadvantage, and ELN score.

Complications from induction chemotherapy, as reflected by intensive care unit admissions during induction, were significantly lower in non-Hispanic White patients (25%) compared with non-Hispanic Black patients (39%) and Hispanic patients (42%). Intensive care unit (ICU) admission rates were significantly higher in patients with morbid obesity and low-tract affluence.

The researchers’ analyses also found that compared with non-Hispanic White ethnicity, minority ethnicity was associated with a 42% increased hazard of death from leukemia (hazard ratio [HR] = 1.42, 95% confidence interval [CI] = 1.09–1.85), and a 36% increased hazard of death from all causes (HR = 1.36, 95% CI = 1.07–1.72), each after controlling for age, sex, and study site. Adjustment for continuous tract disadvantage and affluence and their interaction lowered both the hazard of leukemia and all-cause death to 1.18 (95% CI = 0.88–1.60) and 1.14 (95% CI- 0.88–1.49), respectively. In formal mediation analysis, neighborhood socioeconomic status accounted for 37% (P = .09) and 50% (P = .02) of the racial disparity in death from leukemia and all causes, respectively.

Two limitations of the study are that it looked back at data from patients’ medical records rather than following patients as they moved through diagnosis and treatment to determine obstacles to care, and it was unable to examine possible influences on individual socioeconomic position such as patients’ education level, first language, or household income—data not readily available in patients’ medical records.

Irum Khan, MD

Senior study author Irum Khan, MD, commented in an ASH press release: “These findings point to a need for more research on the social and economic barriers to successful treatment outcomes for patients with AML. Similar to molecular tailoring of therapy, evaluation of social determinants of health should be a key aspect of personalized leukemia therapy. While the field is in its infancy, our analysis suggests that incorporating validated measures of social determinants of health into clinical care is likely to contribute significantly to narrowing disparities in leukemia survival.”

Disclosure: For full disclosures of the study authors, visit ash.confex.com.