Predicting resistance to amyloid-beta deposition and cognitive resilience in the oldest-old

Objective: To explore long-term predictors of avoiding amyloid-beta (Aβ) deposition and maintaining unimpaired cognition as outcomes in the oldest old.

Methods:  In a longitudinal observational cohort study, N=100 former participants of the Ginkgo Evaluation of Memory Study (GEMS; 2000-2008) completed biannual Pittsburgh Compound B (PiB)-PET imaging and annual clinical-cognitive evaluations beginning in 2010. Most recent Aβ status and cognitive status were selected for each participant. Longitudinal outcomes included change in serial Aβ and cognitive tests. Baseline predictors from GEMS included neuropsychological tests, daily functioning, APOE genotype, lifestyle variables, occupational measures, health history, sleep, subjective memory, physical and cognitive activities, depressive symptoms, physical performance and health indices, among others.

Results:  Mean age at last cognitive evaluation was 92.0 years (range 86-100). Mean follow-up time from baseline to last measured Aβ st...