Amyloid load in nondemented brains correlates with APOE e4

Abstract

179 Cognitively healthy adults enrolled in the Sun Health Brain Donation program between 7/91 and 12/07 were at least 60 years old and nondemented at the time of death (21 had developed mild cognitive impairment [MCI]). Amyloid plaque density, congophilic amyloid angiopathy (CAA), and neurofibrillary tangle (NFT) density scores were based on CERAD criteria and compared in apolipoprotein E (APOE) e4 carriers (n=42) and noncarriers (NC) (n=137). Mean age (83.4+/-.6), gender (45% women), interval between death and brain harvest (3.1+/-2.4h), and brain weight (1200+/-119 g) did not differ between e4 carriers (n=42) and NC. Total plaque density was higher in e4 carriers than NC (6.8+/-4.9 vs. 4.3+/-4.4, p=.002), and this was true in each of 5 subregions examined. Total CAA (p=.002) and all subregion CAA burden was also higher in e4 carriers. Total neuritic plaque density (1.2+/-1.0 vs. 1.0+/-1.0, p=.18) and total NFT density (3.9+/-2.4 vs. 3.6+/-2.3, p=.50) did not differ between e4 carriers and NC, nor in any subregion. Eliminating the 21 with MCI did not alter these results. Nondemented APOE e4 carriers over age 60 have a higher burden of total parenchymal and vascular amyloid neuropathology than NC, but no difference in neuritic plaque and NFT pathology.