Impact of Resilience on the Association Between Amyloid-β and Longitudinal Cognitive Decline in Cognitively Healthy Older Adults

Abstract

The present study aims at investigating if the association between amyloid-β and longitudinal cognitive decline in cognitively healthy elderly is modulated by resilience capacity. Resilience capacity was quantified by education, which is a common proxy of resilience and has been shown to be related to a wide range of behaviors promoting resilience. Analyses were conducted with longitudinal cognitive data from the Alzheimer's Disease Neuroimaging Initiative (ADNI). 276 cognitively healthy older individuals (≥56 years) were included in the study. Baseline amyloid pathology was quantified using CSF amyloid-β 1-42 measurements. Longitudinal cognitive decline was assessed using ADAS13, Clinical Dementia Rating - Sum of Boxes, and ADNI-Memory composite scores. Duration of follow-up was 10 years (mean follow-up: 2.6 years). Linear mixed effects models demonstrated stronger cognitive decline over time with increasing baseline amyloid. Subsequent mixed-effects analyses showed that this amyloid-related cognitive decline is stronger in individuals with lower resilience capacity (i.e., lower levels of education). Of note, this effect was not an artifact of differences in neurodegeneration patterns between individuals with lower and higher resilience. Results suggest that resilience capacity has high potential to counteract early amyloid pathology and to significantly slow cognitive decline.

Keywords: Amyloid-β; cognitive decline; healthy older adults; preclinical Alzheimer’s disease; resilience.