Cognitive Function Across Self-Identified Ethno-Racial Groups: The Role of Discrimination, Allostatic Load, and Health Behaviors

Background. Cognitive functioning has been shown to vary by race, education, socioeconomic status, and other demographic factors. Although allostatic load is associated with cognitive functioning this association has not been explored in conjunction with the association between race and cognition and race and allostatic load. Among the literature regarding allostatic load there is a demonstrated gap in research regarding health behaviors and their association with allostatic load beyond controlling for their effect. This research aims to fill these literature gaps and to advance understanding regarding the apparent racial differences in cognitive functioning. Method. Analyses included data from the Multiethnic Study of Atherosclerosis (MESA) parent study and the Stress sub-study from MESA. The first analysis included latent class analysis using biological indicators and latent class regression using health behavior data from the participants in the Stress sub-study. The second analysis was a path analysis including participants who had full allostatic load and cognitive functioning data from the MESA parent study. The third analysis utilized multivariable linear regression with interaction terms and included participants from the parent study who had full discrimination and allostatic load data. Results. Four classes were identified in the sample. The metabolic plus blood pressure class was found to be significantly associated with amount of physical activity and alcohol use. Cognitive function differed by race, amount of discrimination, and allostatic load score. Allostatic load score was associated with race and certain health behaviors. Allostatic load at exam 1 was positively associated with chronic discrimination, however change in allostatic load from exam 1 to exam 5 was negatively associated with chronic discrimination. No form of coping moderated the association between allostatic load and chronic discrimination nor did social support. Internal and external coping styles were found to be associated with baseline allostatic load and change in allostatic load independent of amount of chronic discrimination. Discussion. Differences in cognitive test scores by race beyond amount of discrimination, allostatic load, health behaviors, socioeconomic disadvantage, age, and gender underline the need for further research regarding cognitive functioning among minorities. In light of the rapidly changing ethnic and racial make-up of the aging population these needs take on particular importance. The associations between discrimination and allostatic load highlight the importance of better understanding of how discrimination affects physical health and what factors may mitigate that association. Public health implications are discussed