- Amyloid load in nondemented brains correlates with APOE e4.
Amyloid load in nondemented brains correlates with APOE e4.
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.