Considerations When Accounting for Race and Ethnicity in Studies of Poverty and Neurodevelopment.

Abstract

Objective: Poverty and systemic racism within rare intertwined. Children of marginalized racial and ethnic identities experience higher levels of poverty and adverse psychiatric outcomes. Thus, in models of poverty and neurodevelopment, race and ethnicity-as proxies for exposure to systemic disadvantage-are regularly considered confounders. Recently, however, some researchers claimed that using race and ethnicity as confounders is statistically dubious, and potentially socially damaging. Instead, they argue for the use of variables measuring other social determinants of health (SDoH). We explore this approach.

Method: Data are from 7,836 10-year-olds in the Adolescent Brain and Cognitive Development study. We fit mixed regression models for the association of household poverty measures with psychiatric symptoms, magnetic resonance imaging-derived (MRI) cortical measures, and cognition with and without (1) race and ethnicity adjustment; (2); poverty-by-race and ethnicity interaction terms and (3) alternative SDoH variables. Propensity-based weights were used to calibrate the sample to key US demographics.

Results: For psychiatric and cognitive outcomes, poverty-outcome relationships differed across racial and ethnic groups (poverty-by-race-and-ethnicity interaction p<0.05). For MRI outcomes, adjusting for race and ethnicity changed the estimate of poverty's impact. Alternative SDoH adjustment could not fully account for the impact of race and ethnicity on the associations explored.

Conclusion: Poverty and race and ethnicity combine to influence neurodevelopment. Results suggest effects of poverty are generally inconsistent across race and ethnicity, which supports prior research demonstrating the non-equivalence of SDoH indicators by race and ethnicity. Studies exploring these relationships should assess interaction between poverty and race and ethnicity and/or stratify when appropriate. Replacing race and ethnicity with alternative SDoH may induce bias.