Validation of longitudinal change in proper name recall with pTau217 as a marker of early cognitive decline in cognitively unimpaired adults at risk for Alzheimer's disease dementia.

BackgroundPrevious work has shown that proper name recall from the Logical Memory (LM) task is sensitive to PET and cerebrospinal fluid biomarkers of Alzheimer's disease (AD) in older adult populations. These findings indicate potential utility in identifying preclinical AD.ObjectiveThe purpose of this study is to validate previous findings of the association of proper name recall and blood-based plasma pTau217.MethodsParticipants came from the Wisconsin Registry for Alzheimer's Prevention study. We fit linear mixed effects models of longitudinal LM and proper name recall as a function of most recent pTau217 values. Follow-up analyses added interaction terms to models for group differences in sex and APOE ε4 allele carriage. As an exploratory aim, logistic regression models were used to examine if proper name recall aided in predicting clinical diagnosis.ResultsParticipants with higher concentrations of pTau217 showed a steeper decline on both conventional LM and proper name recall. APOE ε4 allele carriers with higher concentrations of pTau217 showed a greater decline in longitudinal task performance, while there was no significant interaction for sex, indicating that men and women with high pTau217 show similar rates of decline.ConclusionsOur findings validate that proper name recall is sensitive to blood-based pTau217. Measuring proper name recall may be an efficient marker assessing early cognitive change that could be leveraged when designing future cognitive tests.