In:
Alzheimer's & Dementia, Wiley, Vol. 17, No. S6 ( 2021-12)
Abstract:
Cognitive resilience refers to processes involved in coping with effects of brain pathology on cognition. Factors contributing to cognitive resilience against brain atrophy are unclear, as there have been few longitudinal studies investigating this. Therefore we aimed to identify factors explaining the discrepancy between brain atrophy and longitudinal cognitive decline. One proposed method of investigating cognitive resilience is a residual approach, which suggests using the variance in cognition not explained by a specified predictor as a measure of resilience. Method Cognitively unimpaired subjects (n=406) from The Swedish BioFINDER Study with magnetic resonance imaging (MRI) and cognitive test results from at least two time points were included. Using FreeSurfer, global cortical thickness was calculated. A cognitive composite score was calculated from Mini Mental State Examination, Alzheimer´s Disease Assessment Scale – Cognitive Subscale delayed word recall, Trail Making Test B, and Animal fluency. For each subject, the beta coefficients for change in cortical thickness and change in cognition over time were calculated. Linear regression was performed between the two beta coefficients, and the residuals were used as a measure of cognitive resilience. Associations were calculated between this resilience measure and baseline demographics, biomarkers of amyloid (cerebrospinal fluid (CSF) β‐amyloid (Aβ) 42/40 ratio), tau (CSF phosphorylated tau (p‐tau)), and vascular (MRI white matter lesion (WML) volume) pathology as well as neurodegeneration (CSF neurofilament light (NfL)). For dichotomous variables (sex and pathologic Aβ42/40 ratio) independent samples t‐tests, and for continuous variables (all other variables) Pearson correlations, were performed. Result In univariate models, lower age at baseline, female sex, higher cortical thickness and better cognitive results at baseline were associated with higher cognitive resilience against cortical atrophy, while education was not. Further, pathological Aβ42/40 ratio and higher levels of p‐tau, NfL, and WMLs at baseline were negatively associated with cognitive resilience in univariate analyses. In a multivariable linear regression model, lower baseline cortical thickness, a pathological Aβ42/40 ratio, and higher NfL were significantly associated with worse cognitive resilience (Figure 1, Table 1). Conclusion Markers of Alzheimer´s disease pathology and neurodegeneration are associated with worse than expected cognitive decline at a given rate of brain atrophy.
Type of Medium:
Online Resource
ISSN:
1552-5260
,
1552-5279
Language:
English
Publisher:
Wiley
Publication Date:
2021
detail.hit.zdb_id:
2201940-6
