Associations of APOE e2 genotype with cerebrovascular pathology: a postmortem study of 1275 brains.

In this, the largest study of APOE e2 effects on pathologically verified CVD, e2 was not protective against any CVD pathology compared with e3 homozygotes, including CAA. Regarding the latter pathology, e4 was associated with increases in its severity. Furthermore, and perhaps unexpectedly, e2 significantly increased risk of acute/subacute gross haemorrhage in the presence of CAA. Thus, there were limits to e2 neuroprotection against amyloidosis, despite its known and large protective effects against diffuse and neuritic amyloid plaques compared with e3/e3 and e4 carriers in this very collection.