Premium
[IC‐P‐216]: COMPARING IMAGING PHENOTYPES OF AMNESTIC EARLY VERSUS LATE‐ONSET AMYLOID‐NEGATIVE MILD COGNITIVE IMPAIRMENT AND DEMENTIA ADNI SUBJECTS
Author(s) -
Stage Eddie,
Phillips Meredith,
Canela Victor Hugo,
Duran Tugce,
Goukasian Naira,
Rabinovici Gil D.,
Dickerson Bradford C.,
Carrillo Maria C.,
Santi Susan,
Risacher Shan L.,
Saykin Andrew J.,
Apostolova Liana G.
Publication year - 2017
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 - 10.1016/j.jalz.2017.06.2592
Subject(s) - dementia , medicine , pittsburgh compound b , amyloid (mycology) , neuroimaging , alzheimer's disease , apolipoprotein e , cognitive impairment , β amyloid , pathology , psychology , disease , psychiatry
older adults (CN), 4 patients with mild cognitive impairment (MCI), and 1 AD patient underwent frequency doubling technology (FDT-2) to assess contrast sensitivity and [F]Florbetapir PET scans. Both duration of the iterative FDT exam and mean contrast sensitivity were evaluated. Eighteen of the participants also underwent [F]Flortaucipir PET scans. PET scans were processed using standard techniques and intensity-normalized to the whole cerebellum ([F]Florabetapir) or cerebellar crus ([F]Flortaucipir). The associations between contrast sensitivity and both []Florbetapir standardized uptake values with a reference region (SUVR) and [F]Flortaucipir SUVR were evaluated at a voxel-wise level, covaried for age, sex, and diagnosis when appropriate, and displayed at a threshold of p<0.001 (uncorrected) and minimum cluster size (k)1⁄4100 voxels. Mean SUVR from target regions of interest was also extracted, and associations between the regional amyloid and tau measures and contrast sensitivity were assessed using a linear regression model. Results:Significant associations between contrast sensitivity and both amyloid (Figure 1A) and tau (Figure 1B) deposition were observed. The associations remained significant when diagnosis was included as a covariate. When the evaluation was restricted to CNs, significant clusters remained for the association with tau, and at a trend-level for amyloid. Regional associations showed similar patterns of association (Figure 1C and 1D, p<0.01). Conclusions: These findings suggest that visual contrast sensitivity may be associated with two hallmarks of AD, amyloid and tau deposition, perhaps even at preclinical stages. Future studies evaluating longitudinal change in contrast sensitivity over time and/or the ability of contrast sensitivity measures to predict future cognitive decline will provide evidence for use of this tool as an inexpensive, non-invasive biomarker for AD.