Racial discrimination and cognitive function: An instrumental variable analysis

Racial inequities in cognitive function persist with mixed evidence regarding the impacts of racial discrimination on cognitive outcomes. We examined the association between experiences of racial discrimination within institutional settings, such as getting a job or housing, and multiple measures of cognitive function among middle-aged adults using analytic methods to strengthen the existing evidence base and provide potential points for intervention. We used cross-sectional data from 2895 participants in Wave 8 (M_age = 50.20, range: 43-55) and 2618 participants in Wave 9 (M_age = 55.20, range: 48-60) of the Coronary Artery Risk Development in Young Adults (CARDIA) study. Self-reported racial discrimination was operationalized using the Experiences of Discrimination Scale. Cognitive measures included were the Stroop Interference Test, Rey Auditory Verbal Learning Test, Digit Symbol Substitution Test, and the Montreal Cognitive Assessment. Analyses were conducted using ordinary least squares regression (OLS) and instrumental variable (IV) analysis using reflectance meter-measured skin color as the instrument. We find that increased experiences of racial discrimination are associated with poorer performance on cognitive assessments across OLS and IV analyses. For example, reporting one additional experience of racial discrimination was associated with approximately 0.50 SD lower auditory verbal learning scores using IV and 0.08 SD lower scores using OLS (Wave 8 IV 95% CI: -0.54, -0.41; OLS 95% CI: -0.10, -0.06). Such results in a relatively young sample yield insight into the potential implications of navigating a racialized society over one's life course in contributing to inequities in cognitive decline in older age.