Associations between adverse childhood experiences and subjective cognitive decline: A scoping review

Background: Long-term health effects of adverse childhood experiences (ACEs) include cognitive decline that occurs later in life. Subjective cognitive decline (SCD), recognized as an early indicator of Alzheimer's disease, may present an essential period for intervention in populations with ACEs. Objective: This review aims to explore the associations between ACEs and SCD, while examining the potential moderating effects of sociodemographic factors Methods: A systematic search of four databases (Medline, PsycINFO, CINAHL, and Web of Science) was conducted from inception to July 2024. Eligible studies included adults with a history of ACEs and self-reported SCD. In total, twelve studies were included, primarily using U.S.-based samples, with sample sizes ranging from 46 to over 195,000 participants. Results: The evidence of a dose-response relationship highlights the link between ACEs and SCD. The risk of SCD increases among adults over 65, lower-income groups, and sexual minorities. However, gender differences were inconsistently observed across studies. Mental health conditions, particularly depression is a significant risk factor. Conclusions: Early screening and intervention for SCD among individuals with high ACE exposure may help delay the progression to severe cognitive impairment. However, the reliance on cross-sectional studies and high risk of bias limit causal inferences. Future research should explore longitudinal studies with diverse populations to clarify causal pathways and the role of sociodemographic factors in the ACE-SCD relationship.