Fig. 3.

Effect of APOE allele status in aMCI. (A) Cortical regions showing significant thinning in the APOE-ε4 carriers vs. noncarriers within the aMCI phenotype. (B) Thinning cortex in the APOE-ε4 carriers (blue) compared with the noncarriers (pink) was consistent across disease pathologies. Note that there were only four APOE-ε4 carriers in the PD amnestic phenotypes. The differences in cortical thickness in the middle temporal gyrus are minimal in the PD group. (C) In the refined cohort with amyloid-negative controls, amyloid-positive AD-aMCI individuals, and amyloid-negative PD-aMCI individuals, the ε4 carriers show lower cortical thickness in the precuneal region compared with the noncarriers. This effect is observed in both AD and PD-MCI groups, that is, precuneal thinning in ε4 carriers is independent of pathologic disease origins. ∗ Denotes mean values for each group. Abbreviations: AD, Alzheimer's disease; APOE, apolipoprotein E; aMCI, amnestic mild cognitive impairment; MCI, mild cognitive impairment; PD, Parkinson's disease.