Mechanisms underlying the association between adverse childhood experiences and racial disparities in later-life cognition.

Objective: Adverse childhood experiences (ACEs) may be a risk factor for later-life cognitive disorders such as dementia; however, few studies have investigated underlying mechanisms, such as cardiovascular health and depressive symptoms, in a health disparities framework.

Method: 418 community-dwelling adults (50% nonHispanic Black, 50% nonHispanic White) aged 55+ from the Michigan Cognitive Aging Project retrospectively reported on nine ACEs. Baseline global cognition was a z-score composite of five factor scores from a comprehensive neuropsychological battery. Depressive symptoms were assessed using the Center for Epidemiologic Studies Depression Scale. Cardiovascular health was operationalized through systolic blood pressure. A mediation model controlling for sociodemographics, childhood health, and childhood socioeconomic status estimated indirect effects of ACEs on global cognition via depressive symptoms and blood pressure. Racial differences were probed via t-tests and stratified models.

Results: A negative indirect effect of ACEs on cognition was observed through depressive symptoms [β = -.040, 95% CI (-.067, -.017)], but not blood pressure, for the whole sample. Black participants reported more ACEs (Cohen's d = .21), reported more depressive symptoms (Cohen's d = .35), higher blood pressure (Cohen's d = .41), and lower cognitive scores (Cohen's d = 1.35) compared to White participants. In stratified models, there was a negative indirect effect through depressive symptoms for Black participants [β = -.074, 95% CI (-.128, -.029)] but not for White participants.

Conclusions: These results highlight the need to consider racially patterned contextual factors across the life course. Such factors could exacerbate the negative impact of ACEs and related mental health consequences and contribute to racial disparities in cognitive aging.