The Relation between Discrimination and Cognitive Function: Moderating and Mediating Factors

Abstract

Discrimination is a chronic stressor that disproportionately affects African Americans. Chronic stress itself is a risk factor that has been linked to a plethora of negative brain health outcomes across the lifespan in both animal and human models that include damaging changes in brain structure and function, cognitive decline and increased risk for dementia. Despite an increasingly aging population, and that African Americans are disproportionately burdened by cognitive decline and dementia, little research has examined the relations of discrimination to cognitive functioning among African Americans. Using data from the Healthy Aging in Neighborhoods of Diversity across the Life Span study, multiple regression analyses were conducted on a sample of 946 socioeconomically diverse African Americans (mean age = 47.4 years old, 56.2% female, 50.1% above the poverty line) to examine the interactive relations of discrimination (assessed by the Williams' Everyday Discrimination Scale), age and poverty status on cognitive functioning. Further analyses examined potential biobehavioral mediators of the relation of discrimination to performance on neuropsychological measures. Results revealed no significant three-way interactions of discrimination, age, and poverty status or two-way interactions of discrimination and age with respect to cognitive outcomes. There was only one significant two-way interaction of discrimination and poverty status on the Digit Span Forward subtest (p < .05), such that attention was better for those who reported higher levels of discrimination and were above the poverty line, but worse for those who reported higher levels of discrimination and were below the poverty line. Results also revealed one significant association of discrimination and cognitive function such that higher levels of discrimination were related to higher scores on a measure of memory, the CVLT short delay free recall (p < .05). No proposed candidate mediator attenuated the significant findings. Results indicate a relative absence of a relation of discrimination, and its interaction with age and poverty status, with cognitive function in the present, predominantly middle-aged African American sample. While the minimal significant findings may be spurious, it is possible that relations of discrimination to cognitive function may vary by socioeconomic conditions in select instances. Because the present sample was much younger than prior investigations that noted significant relations of discrimination to cognitive function, it is plausible that such associations may not be seen earlier in the lifespan. While the findings of this study were largely nonsignificant, the results represent an important contribution to the field in understanding the complex relations between discrimination and cognition among African Americans in different sociodemographic groups across the lifespan. Future research investigating relations of discrimination to cognitive function, and associated underlying mechanisms, remains critical to inform efforts to reduce racial disparities in cognitive impairments.