Amyloid beta-protein length and cerebral amyloid angiopathy-related haemorrhage

The relationship between amyloid beta-prorein (A beta) length and the apoli poprotein E (APOE) epsilon 2 allele, which is over-represented in cerebral amyloid angiopathy-related haemorrhage (CAAH), has not previously been exam ined. Of 57 CAA patients studied, 37 had CAAH. All patients, particularly t hose with CAAH had more blood vessels immunoreactive for A beta 40 than A b eta 42 in both the leptomeninges and cerebral cortex. CAAH patients had mor e A beta 40-immunoreactive blood vessels in the leptomeninges (p < 0.001) a nd cortex (p = 0.027) than had non-haemorrhage patients. Cortical blood ves sels, the usual source of haemorrhage in CAAH, were more frequently A beta 42 immunoreactive in APOE epsilon 2 carriers than in non-epsilon 2 carriers (p=0.022). The APOE epsilon 2 allele may predispose to CAAH by increasing the seeding of cortical blood vessels by A beta 42. NeuroReport 11:937-940 (C) 2000 Lippincott Williams & Wilkins.