The impact of poverty and low socioeconomic status on health and survival among children may be even more debilitating than suspected, according to new data presented at ASH 2019. Even in clinical trials, which are designed to provide consistent treatment across groups, socioeconomic status was associated with “substantial” differences in survival, researchers were surprised to find out.
The first national evaluation of socioeconomic status, by geographic areas, in pediatric patients with acute myeloid leukemia (AML) showed that children from poorer neighborhoods were nearly 2.5 times more likely to die during treatment compared with children from high-income areas. The data also demonstrated an increased risk for relapse among patients from low-income areas versus high-income areas.
Geography-Based Socioeconomic Disparities
“We expected there to be a difference, but the degree of difference is quite substantial,” said lead study author Lena E. Winestone, MD, MS, MSHP, Pediatric Hematologist and Oncologist, Division of Allergy, Immunology, and BMT, UCSF Benioff Children’s Hospital, San Francisco, CA.
“This finding is quite robust in the context of the other covariates, and the effect of area-based socioeconomic status is not attenuated by race or by any of the biologic risk factors that we looked at,” she said.
Dr Winestone and colleagues examined the role of area-based measures of socioeconomic status as contributors to clinical outcome disparities in 2 recent Children’s Oncology Group phase 3 clinical trials in AML. Although the researchers hypothesized that pediatric patients with AML from low-income and low-education zip codes would have inferior survival rates compared with patients from higher-income areas, the extent of the difference characterized was “alarming.”
Even after adjusting for insurance type, race, and known biologic risk factors, low-income neighborhoods were significant predictors of survival, Dr Winestone reported.
The findings showed that the 5-year survival of patients from middle- or high-income areas was 68% compared with 61% among patients from low-income areas, and only 43% among patients living in poverty. Researchers also identified greater risk for relapse and greater treatment-related mortality among patients from low-income areas versus high-income areas.
“Even with access to the same care, patients from poorer neighborhoods are far more likely to die,” said Dr Winestone, noting that the exact reasons behind the increased risk for death remain unknown.
Collecting individual data on patients’ socioeconomic status at the time of enrollment in future clinical trials may help researchers “dig deeper into the question of how circumstances outside of the clinical aspects of disease” affect health outcomes, Dr Winestone said.
“I think the mechanisms underlying these disparities are important to understand,” Dr Winestone added. “I’m also hopeful that as we continue to perform analyses and study the timing of these deaths, we may be able to think about how to intervene to improve these disparities.”
Racial Disparities in Clinical Trials Harm Patients and Drug Development
A second study presented at ASH 2019 addressed the issue of racial disparities in clinical trials. Researchers unanimously agree that greater access to clinical trials among minorities and diverse populations of patients is essential for developing appropriate treatments to different populations and improving patient care. Nevertheless, the data from this new study suggest that adult minorities (aged ≥18 years) with AML may be unnecessarily excluded from enrollment in clinical trials.
The findings come from a study of 1040 adults with AML, which showed that although African Americans were more likely to have evidence of abnormal kidney functioning than whites, this finding was not associated with any difference (P = .68) in their ability to receive intensive therapy or in overall survival in this patient population.
Furthermore, African Americans presented with similar rates of comorbidities other than renal function, including cardiac and liver functions. In addition, there was no association between comorbidities or organ function and overall survival. The median overall survival and complete response rate did not differ by race.
The study investigators noted that these findings have important implications for the design of future clinical trials.
“If we’re able to liberalize renal function eligibility criteria, this may reduce racial disparities in clinical trial enrollment, which may be an important, first step in improving diversity of cancer clinical trial patient populations,” said lead study author Abby Statler, PhD, MPH, MA, Cancer Biostatistics, Cleveland Clinic, OH.
“Second, if more minority patients are eligible for clinical trials, we may be able to reduce the inequitable access to investigational products, which may allow a more diverse patient population to benefit from novel therapies, which is extraordinarily important in the context of a life-threatening disease such as AML,” Dr Statler added.
“Finally, if future clinical trials incorporate liberalized eligibility criteria that promote accrual among minority patient populations, then the outcomes from these clinical trials would be more applicable to a diverse array of cancer patients, particularly those patients that have been underrepresented in clinical trials over the last several decades,” Dr Statler concluded.