Insights into the pathogenesis and pathogenicity of cerebral amyloid angiopathy.

Amyloid-beta (Abeta) cerebral amyloid angiopathy (CAA) affects most Alzheimer's disease (AD) patients and ~30% of otherwise-normal elderly people. APOE epsilon 4 is a major risk factor for CAA in AD. Neurons are probably the source of the vascular Abeta.