Role of Discrimination and Physiological Dysregulation in Racial Disparities in Cognitive Function: The Multi‐Ethnic Study of Atherosclerosis (MESA)

Abstract

AbstractBackgroundBlack‐White disparities in cognitive test scores are well documented. Studies suggest that structural racism‐related factors like quality of education and cumulative stress exposure may contribute to disparities in inflammation and cardiometabolic health that undergird racial disparities in Alzheimer’s disease and cognitive health.MethodWe used MESA data from (N = 1,839) participants that self‐report being racialized as Black or White. We used path analyses to examine the association between racialized group and age‐ and education‐adjusted cognitive scores from the Cognitive Ability Screening Test (CASI) at Exam 5 (2010‐12) and Exam 6 (2016‐18). We examined the relationship between discrimination using the Everyday Discrimination Scale at Exam 1 (2000‐02) and physiological dysregulation at Exam 5 (using a cardiometabolic index = waist‐to‐hip ratio, triglycerides, low‐density lipoprotein cholesterol, high‐density lipoprotein cholesterol, glucose, systolic blood pressure, resting heart rate, and pulse pressure). All models were adjusted for Exam 5 age, sex, site, depression, general stress, socioeconomic stress, and APOE‐e4.ResultMean age was 69.6 years (SD = 9.3) at Exam 5. Participants racialized as Black had significantly lower CASI scores at Exam 5 (b = ‐0.26) and Exam 6 (b = ‐0.29) than counterparts. Physiological dysregulation was directly associated with lower CASI scores at both exams (Table 1). Discrimination and physiological dysregulation had a significant indirect association with racialized group‐cognition at both exams (Figure 1). Physiological dysfunction was associated with lower CASI scores for participants racialized as Black compared to White at Exam 5 (b = ‐0.004, 95% CI: ‐0.010, ‐0.001) and Exam 6 (b = ‐0.005, 95% CI: ‐0.011, ‐0.002). Higher discrimination was associated with higher CASI scores for participants racialized as Black compared to White at Exam 5 (b = 0.013, 95% CI: 0.001, 0.024) and Exam 6 (b = 0.012, 95% CI: 0.001, 0.024). There was no racialized difference in decline from Exam 5 to Exam 6.ConclusionPhysiological dysregulation may be a mechanism to partially explain the Black‐White disparity in cognitive test scores among middle‐aged and older adults. Endorsing more everyday discrimination was associated with a significantly higher cognitive test scores, though further research is needed to determine if this is due to coping‐related resilience.