APOE and vascular disorder: •Accumulation of amyloid-β (Aβ) in the cortical walls (type 1) and leptomeningeal small arteries, but not capillaries (type 2) due to vascular occlusion and rupture•Vasculopathy (i.e., fibrinoid necrosis, loss of smooth muscle cells, wall thickening, perivascular blood breakdown, and microaneurysm)•APOE gene polymorphism (i.e., APOE ε2 and APOE ε4 allele related to types 2 and 1, respectively)