Early Life Determinants of Late-Life Cognition: Stress and Adversity Across the Lifespan and its Long-Term Impacts on Cognition

Across populations, it is not uncommon for people to experience one or more adverse events in childhood. The effect of stress on cognition has been examined at discrete periods of development (e.g., childhood, adulthood, and older adulthood) but not extensively studied from a longitudinal perspective. The purpose of this study was to examine the association between early-life adversity/childhood adversity (CADV) and cumulative lifecourse adversity (CLADV), via salivary cortisol, with cognitive functioning in mid-late life. Two models were assessed: the first, examined the relationship between CADV and cognition and the second examined the relationship between CLADV and cognition. Both the direct effects and the indirect effects were assessed. The indirect effects pathway examined whether the effect of CADV and CLADV are mediated through physical health (PH) and mental health/psychological well-being (MHW). Multigroup analyses were carried out to determine whether sex differences were present. Results from the current study revealed childhood adversity predicts executive functioning (EF) and episodic memory (EM) in late midlife, with this association being mediated by both mental/psychological well-being and physical health. Similar results were noted when examining the association between cumulative lifecourse adversity and both cognitive domains. Results confirmed hypotheses that the relationships between adversity and cognitive functioning is largely mediated by MHW and PH, given that early life adversity can lead to a cascade of challenges and more adversity across the lifespan, which may “weather down” individuals over time. Findings from these analyses noted that the measurement of how adversity impacts cognitive functioning differs between females and males. Exploratory analyses which assessed the moderating role of parental affection on adversity’s effect on cognition revealed that it did not significantly moderate either the direct or indirect relationships between adversity (childhood and cumulative lifecourse) and EF and EM abilities. Overall, this work highlights the importance of bolstering well-being across the lifespan rather than limiting target interventions to a specific point in development by showing the influence adversity has on cognition in later life is mediated through MHW and PH factors.