TITLE:
FDG and Amyloid PET in Cognitively Normal Individuals at Risk for Late-Onset Alzheimer’s Disease
AUTHORS:
John Murray, Wai H. Tsui, Yi Li, Pauline McHugh, Schantel Williams, Megan Cummings, Elizabeth Pirraglia, Lilja Solnes, Ricardo Osorio, Lidia Glodzik, Shankar Vallabhajosula, Alexander Drzezga, Satoshi Minoshima, Mony J. de Leon, Lisa Mosconi
KEYWORDS:
Alzheimer’s Disease, Early Detection, Positron Emission Tomography, Amyloid Imaging, Glucose Metabolism, Normal Aging
JOURNAL NAME:
Advances in Molecular Imaging,
Vol.4 No.2,
April
16,
2014
ABSTRACT: Having a parent affected by late-onset Alzheimer’s disease (AD) is a
major risk factor for cognitively normal (NL) individuals. This study explores
the potential of PET with 18F-FDG and the amyloid-β (Aβ)
tracer 11C-Pittsburgh Compound B (PiB) for detection of individual
risk in NL adults with AD-parents. Methods: FDG- and PiB-PET was performed in
119 young to late-middle aged NL individuals including 80 NL with positive
family history of AD (FH+) and 39 NL with negative family history of any
dementia (FH-). The FH+ group included 50 subjects with maternal (FHm) and 30
with paternal family history (FHp). Individual FDG and PiB scans were Z scored
on a voxel-wise basis relative to modality-specific reference databases using
automated procedures and rated as positive or negative (+/-) for AD-typical
abnormalities using predefined criteria. To determine the effect of age, the
cohort was separated into younger (49 ± 9 y) and older (68 ± 5 y) groups relative
to the median age (60 y). Results: Among individuals of age >60 y, as
compared to controls, NL FH+ showed a higher frequency of FDG+ scans vs. FH- (53% vs. 6% p β pathology in the younger cohort,
suggesting that neuronal dysfunction may precede major aggregated Aβ burden in young NL FH+. Longitudinal
follow-up is required to determine if the observed abnormalities predict future
AD.