EDUCATION AND THE ONSET OF COGNITIVE PATHOLOGY: A LONGITUDINAL ANALYSIS OF ACCELERATED COGNITIVE DECLINE

摘要

The role of socioeconomic status (SES) as risk factors for Alzheimer’s disease and related dementias (ADRD) is challenged by a lack of consistency in predicting cognitive decline. This lack of consistency has been explained as resulting from educational attainment being associated with baseline functioning, but not with the risk of age-related cognitive decline. Fundamental causes theory clarifies that education usually operates on multiple mechanisms, but may reliably predict a subtype of cognitive decline relating specifically to ADRD-related pathology since education also predicts risk factors for ADRD. In this study, we examined the role of education as a risk factor for normal cognitive aging as well as ADRD-related cognitive pathology. Data from a nationally representative prospective cohort study (N=29,262) of older U.S. residents were used. Analyses layered Cox proportional hazards models over longitudinal mixed-effects models to jointly model cognitive aging and incidence of ADRD-related cognitive pathology. Model fit improved over random slopes models. Replication was completed using data from the Integrative Analysis of Longitudinal Studies on Aging research programme. Life-expectancy ratios (LER) with 95% confidence intervals were reported. Results revealed that increased education was associated with later onset of ADRD-related cognitive pathology. Models adjusted for common confounders including depressive symptoms and major strokes. Education was associated with longer healthy life expectancy free of cognitive pathology, with delays as great as 2.4 years in healthy life expectancy for a university degree among individuals aged 50 and older. Follow-up work should seek to consider mechanisms explaining associations identified herein.