Racial discrimination may adversely impact cognition in African Americans
Experiences of racism are associated with lower subjective cognitive function (SCF) among African-American women.
Rates of incident dementia and Alzheimer's Disease (AD) are higher in African Americans than in white Americans. In many studies, older African Americans perform more poorly on neuropsychological cognition tests compared to white Americans. Experiences of racism are common among African Americans, with 50 percent or more respondents to a 2017 national survey reporting such experiences. These institutional and daily forms of racism have been associated with increased risks of various conditions that can impair cognition, including depression, poor sleep, type 2 diabetes and hypertension.
Using data from the Black Women's Health Study (a prospective cohort study established in 1995, when 59,000 black women aged 21 through 69 years enrolled by completing health questionnaires) researchers from Boston University's Slone Epidemiology Center quantified the association between experiences of racism and SCF, based on six questions about memory and cognition.
They found that experiences of both daily and institutional racism were associated with decreased SCF. Women reporting the highest level of daily racism had 2.75 times the risk of poor SCF as women reporting the lowest level of daily racism. Women in the highest category of institutional racism had 2.66 times the risk of poor SCF as those who reported no such experiences.
"Our findings of a positive association of experiences of racism with poorer subjective cognitive function are consistent with previous work demonstrating that higher perceived psychological stress is associated with greater subjective memory decline," explains senior author Lynn Rosenberg, ScD, epidemiologist at the Slone Epidemiology Center at Boston University and a principal investigator of the Black Women's Health Study. "Our work suggests that the chronic stress associated with racial discrimination may contribute to racial disparities in cognition and AD," added Rosenberg, who is also a professor of epidemiology at Boston University School of Public Health.
Future work is needed to examine whether exposure to institutional and daily racism accelerates conversion to Alzheimer's dementia and/or increases levels of AD biomarkers, such as cerebrospinal fluid or PET markers of amyloid-β and tau pathology, according to the researchers.
These findings appear online in the journal Alzheimer's & Dementia: Diagnosis, Assessment & Disease Monitoring.