ASPO Abstracts
Does socioeconomic status account for racial and ethnic disparities in childhood cancer survival?
Category: Cancer Health Disparities, Lifestyles Behavior, Energy Balance & Chemoprevention
Conference Year: 2018
Abstract Body:
Background: For many childhood cancers, survival is lower in non-Hispanic blacks and Hispanics compared to non-Hispanic whites, which may be attributed to underlying socioeconomic factors. However, prior childhood cancer survival studies have not formally tested for mediation by socioeconomic status (SES). Purpose: The purpose of this study was to utilize causal mediation methods to quantify the role of SES in explaining racial and ethnic disparities in survival for several different types of childhood cancer. Methods: We used population-based cancer survival data from the Surveillance, Epidemiology, and End Results 18 database for non-Hispanic black, non-Hispanic white, and Hispanic children, ages 0-19 years, diagnosed 2000-2011 (N=31,866). We estimated black-white and Hispanic-white mortality hazard ratios (HR) and 95% confidence intervals (CI), adjusted for age, sex, and stage at diagnosis. We used the inverse odds weighting method to test for mediation by SES, which was measured with a validated census tract composite index. Results: Non-Hispanic white children had a significant survival advantage over non-Hispanic black and Hispanic children for several cancers including leukemias, lymphomas, central nervous system tumors, neuroblastoma, and soft tissue sarcomas. SES significantly mediated the race/ethnicity-survival association for acute lymphoblastic leukemia, acute myeloid leukemia, neuroblastoma, and non-Hodgkin lymphoma; SES reduced the original association between race/ethnicity and survival by 44%, 28%, 49%, and 34% respectively for non-Hispanic blacks vs. non-Hispanic whites, and by 31%, 73%, 48%, 28% respectively for Hispanics vs. non-Hispanic whites. Conclusions: SES mediates racial/ethnic childhood cancer survival disparities to varying degrees across cancers. The proportion of the total racial/ethnic survival disparity explained by SES varies between black-white and Hispanic-white comparisons for some cancers, suggesting that mediation by other factors differs across groups.
Keywords: childhood cancer survival, racial and ethnic disparities, socioeconomic status