PET Tau and Amyloid-β Burden in Mild Alzheimer's Disease: Divergent Relationship with Age, Cognition, and Cerebrospinal Fluid Biomarkers.
File(s)
Author(s)
Type
Journal Article
Abstract
BACKGROUND: Combining PET amyloid-β (Aβ) and tau imaging may be critical for tracking disease progression in Alzheimer's disease (AD). OBJECTIVE: We sought to characterize the relationship between Aβ and tau ligands as well as with other measures of pathology. METHODS: We conducted a multi-center observational study in early AD (MMSE >20) participants aged 50 to 85 y. The schedule included cognitive assessments (ADAS-Cog) and CSF measurement of Aβ and tau at baseline and 6 months; PET-CT imaging with Aβ ([18F]AV45) and tau ([18F]AV1451) ligands at baseline. RESULTS: 22 participants took part in the study with 20 completing its 6-month duration and 12 having both tau and amyloid PET. The PET biomarker analysis revealed a strong negative correlation between age and tau in multiple regions. Entorhinal cortex tau and age interacted significantly in terms of cognitive change over 6 months which may have been to older participants deteriorating faster despite lower levels of cortical tau. Cortical Aβ associated with entorhinal cortex tau while CSF tau/Aβ ratio correlated strongly with cortical tau but not Aβ. CONCLUSION: The negative relationship between age and cortical tau whereby younger patients with mild AD had relatively greater tau burden is potentially important. It suggests that younger-age onset AD may be primarily driven by tau pathology while AD developing later may depend on a multitude of pathological mechanisms. These data also suggest that PET-tau performs better than PET-amyloid in predicting the best validated AD diagnostic marker- the CSF total tau/Aβ ratio.
Date Issued
2017-08-29
Date Acceptance
2017-06-30
Citation
JOURNAL OF ALZHEIMERS DISEASE, 2017, 60 (1), pp.283-293
ISSN
1387-2877
Publisher
IOS Press
Start Page
283
End Page
293
Journal / Book Title
JOURNAL OF ALZHEIMERS DISEASE
Volume
60
Issue
1
Copyright Statement
This article is published online with Open Access and distributed under the terms of the Creative Commons Attribution License (CC-BY 4.0)
License URL
Identifier
PII: JAD170129
Subjects
Alzheimer’s disease
amyloid beta-peptides
cerebrospinal fluid proteins
positron emission tomography
tau proteins
Publication Status
Published