Premium
Pathological correlates of impaired self‐awareness of memory function in dementia
Author(s) -
Gagliardi Geoffroy Pierre,
Kuppe Madeline,
Hanseeuw Bernard,
Lois Cristina,
Vannini Patrizia
Publication year - 2020
Publication title -
alzheimer's and dementia
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 6.713
H-Index - 118
eISSN - 1552-5279
pISSN - 1552-5260
DOI - 10.1002/alz.047694
Subject(s) - clinical dementia rating , pathological , dementia , anosognosia , psychology , entorhinal cortex , medicine , cohort , disease , alzheimer's disease neuroimaging initiative , hippocampus
Background Impaired self‐awareness of memory function (a.k.a. anosognosia) is a common symptom observed in Alzheimer’s disease (AD), however it’s pathological correlates remain unclear. Here we investigated the impact of amyloid and tau on memory self‐awareness in a cohort of clinically normal or impaired participants. Method This study included 216 clinically normal (CDR=0) and 156 clinically impaired (CDR≥0.5) participants part of the Alzheimer's Disease Neuroimaging Initiative (ADNI) project. Using the E‐Cog memory subscale, a participant‐informant discrepancy index was computed such that a negative score indicates a participant’s underestimation of difficulties as compared to the partner. Linear models were performed with discrepancy as the dependent variable, and amyloid ( Florbetapir ) from global region of interest (ROI) and tau ( Flortaucipir ) from two ROI (i.e. inferior temporal and entorhinal cortices in two separate models) as independent variables. Demographics (i.e. Age, Gender, Years of Education) were added as covariates. Result We found that clinically impaired individuals were significantly older (p = 0.01), more educated (p < 0.001), and included more women (p = 0.01) as compared to the clinically normal group. In general, clinically impaired individuals had lower awareness scores as compared to clinically normal individuals (p < 0.001). A significant three‐way interaction was observed between clinical status and biomarkers (i.e., amyloid and tau burden, p = 0.009 and 0.033 for entorhinal and inferior temporal cortices, respectively). Post hoc analyses revealed no significant difference between groups in individuals at low levels of pathology (p > 0.05; Figures A and B, right panels). However, at higher levels of pathology (i.e., both amyloid and tau), clinically impaired individuals demonstrated significantly lower awareness scores as compared to clinically normal participants (Figures A and B, left panels). Conclusion These findings better characterize the evolution of anosognosia in AD. Specifically, data suggest that impaired self‐awareness of memory function is associated with higher levels of amyloid and tau, providing further support that discordant subjective and objective measures may be important for clinical consideration.