Early life factors and dementia risk: A study of adverse childhood experiences and later-life cognition and behaviour

Objectives: Adverse childhood experiences (ACE) are associated with brain alterations and cognitive decline. In later life, cognitive impairment and mild behavioural impairment (MBI) are associated with greater dementia risk. We investigated whether more severe ACE are cross-sectionally associated with worse later-life cognitive and behavioural symptoms. Study design: Cross-sectional study. Methods: Data are from the Canadian Platform for Research Online to Investigate Health, Quality of Life, Cognition, Behaviour, Function, and Caregiving in Aging (CAN-PROTECT). Measures included the Childhood Trauma Screener (CTS-5), neuropsychological testing, Everyday Cognition (ECog)-II scale, and MBI Checklist (MBI-C). Linear regressions modelled associations between ACE severity and neuropsychological test scores. Multivariable negative binomial regressions (zero-inflated, if appropriate) modelled associations between ACE severity and ECog-II and MBI-C scores. All models controlled for age, sex, education, and ethnocultural origin. Clinical diagnoses of depression and/or anxiety were explored as covariates or mediators. Results: In adjusted analyses, higher ACE scores were associated with worse performance on Trail-Making B (standardized b = 0.10, q = 0.003), Switching Stroop (b = -0.08, q = 0.027), Paired Associates Learning (b = -0.08, q = 0.049), and Digit Span (b = -0.08, q = 0.029). Higher ACE scores were also associated with higher ECog-II (b = 1.08, q = 0.029) and MBI-C (b = 1.20, q <0.001) scores; these associations were neither mediated by affective symptoms (ECog p = 0.16; MBI p = 0.13) nor moderated by sex (ECog p = 0.09; MBI p = 0.46). Conclusion: Older adults with a history of more severe ACE show greater cognitive and behavioural risk markers for dementia that cannot be explained by previous psychiatric history. Further research into ACE as an early modifiable risk factor for dementia is warranted.