Becker JA, Carmasin J, Maye J, Rentz DR, Buckner RL, Sperling RA, Johnson KA.
Amyloid deposition and FDG metabolism in relation to age in APOE4 carriers.
Human Amyloid Imaging 2010 Meeting Abstracts. 2010 April 9;
Background: APOE4 carrier status in normal individuals has been associated with both altered glucose metabolism
and higher levels of amyloid deposition.
Objective: To evaluate the impact of APOE-ε4 carrier status on FDG metabolism considering the effects of PiB
retention, cortical thickness and age in cognitively normal (CN) older individuals.
Methods: Forty-three CN subjects, mean age ± SD = 75.6 ± 7.0 (11 ε4 carriers, mean age = 73.4 ± 7.6, and
32 ε4 non-carriers, mean age = 76.4 ± 6.8) underwent PiB (DVR, cerebellar cortex reference region) and FDG (SUV,
covariance adjusted for cerebellar cortex SUV) PET and MR imaging; image data was processed using Freesurfer.
FDG analyses were performed vertex-wise controlling for precuneus PiB retention, cortical thickness local to each
vertex, and age, in order to isolate APOE-ε4 effects on metabolism.
Results: Compared to non-carriers, ε4 carriers had similar precuneus, parietal, frontal and global amyloid deposition,
but exhibited hypometabolism in default network areas and hypermetabolism in prefrontal, inferomedial temporal
and caudal anterior cingulate regions (cluster-wise corrected pConclusions: These preliminary results in 43 CN subjects suggest that certain frontal and anterior cingulate
regions of relative hypermetabolism may mark an important intermediate step along a trajectory of prodromal AD.