Cerebral amyloid angiopathy

Cerebral amyloid angiopathy (CAA) is characterized by beta-amyloid deposition within cerebral blood vessels and constitutes an age-related vascular pathology associated with intracerebral hemorrhages and cognitive impairment. CAA is a major contributor to a subtype of stroke with high mortality, morbidity, and recurrence rates. The sporadic, familial, and iatrogenic variants of CAA have distinct epidemiological profiles. Inflammatory mechanisms exacerbate amyloid-induced vascular injury and may cause a distinct subtype of CAA-related inflammation. In 2022, an international collaborative study updated and validated the Boston Diagnostic Criteria (Version 2.0) for CAA across the full spectrum of clinical manifestations. Cognitive impairment in CAA generally manifests in three types: gradual functional decline, stepwise functional decline, and rapidly progressive cognitive deterioration associated with inflammation. CAA is strongly associated with Alzheimer’s disease (AD). While both conditions involve amyloid-β (Aβ) accumulation, their anatomical distributions differ. In AD, Aβ deposits mostly in the frontal and parietal association cortices. CAA is observed in approximately 90% of AD cases, and the coexistence of AD and CAA correlates with more severe disease progression.