Childhood and Adulthood Stress Exposures in Relation to Late-Life Cognitive Function: A Life Course Perspective

Abstract

Thesis (Ph.D.)--University of Rochester. School of Medicine & Dentistry. Dept. of Public Health Sciences, 2017.Background: Chronic stress exposures are believed to cause alterations in neurobiological systems as wells as structural atrophy in specific brain regions. Because of this dysregulation, stress exposures are associated with a wide range of health outcomes, in particular, cognitive function. Principles of life course epidemiology are needed to understand how stress exposures in different developmental periods are interrelated and how these processes may influence late-life cognitive function. Methods: Data from the publicly available 2008, 2010, and 2012 Health and Retirement Study (HRS) were used to address Specific Aims 1 and 2. Participants who received the psychosocial lifetime questionnaire that included items on stress exposures will be identified. The HRS measured global cognitive function using the Telephone Interview for Cognitive Status (TICS). Bivariate analyses will compare mean TICS scores and the distributions of potential confounders across stress exposures in childhood and adulthood. Subsequently, multivariable analyses including mixed-effects linear regression models and marginal structural equation models for mediation will be used to assess the relationships between childhood and adulthood stress exposures and late-life cognitive function. Specific Aim 3 imputed domain specific cognitive function scores for HRS participants applying data fusion that will use the National Health and Nutrition Examination Survey III as the donor file. Linear regression models evaluated the association between childhood stress exposures and late-life domain specific cognitive function and whether these relationships are modified by social support. Results: A total of 3,433 participants met inclusion criteria. Both childhood and adulthood stress exposures were associated with late-life cognitive function. Only the childhood (and not the adulthood or total score) was associated with late-life cognitive function. Death of a child mediated the relationship between the childhood cumulative score and late-life cognitive function. Conclusions: Childhood stress exposures, in particular they accumulate, have the most detrimental effect on late-life cognitive function. Future endeavors may apply results from this dissertation to investigate biological mechanisms that may explain etiologic pathways that link stress exposures to cognitive disorders such as dementia and Alzheimer’s diseas