Cerebral amyloid angiopathy in the aged

Area of Science:

• Neuropathology
• Neurodegenerative Diseases
• Aging

Background:

• Cerebral amyloid angiopathy (CAA) is a cerebrovascular disease characterized by amyloid deposition in the walls of cerebral arteries.
• CAA is increasingly recognized as a significant factor in cognitive decline and brain aging.

Purpose of the Study:

• To investigate the prevalence, characteristics, and associations of cerebral amyloid angiopathy (CAA) in an elderly autopsy cohort.
• To explore the relationship between CAA, brain aging, dementia of Alzheimer type (DAT), and lobar cerebral hemorrhage.

Main Methods:

• Autopsy brains from 123 individuals aged 59-101 years were examined for CAA.
• Immunohistochemistry was used to characterize the amyloid deposits.
• Correlation analyses were performed to assess the relationship between CAA, age, senile plaques, neurofibrillary tangles, and dementia status.

Main Results:

• CAA was detected in 57% of the brains, with incidence increasing with age and most frequent in the occipital cortex.
• CAA amyloid was positive for amyloid P component and negative for AA protein and prealbumin.
• CAA presence and severity correlated significantly with senile plaques and neurofibrillary tangles.
• Incidence of CAA was 88% in patients with dementia of Alzheimer type (DAT), significantly higher than in non-Alzheimer dementia.
• Lobar cerebral hemorrhage was observed in 3 patients with moderate to marked CAA.

Conclusions:

• CAA is a common finding in the aging brain and is pathogenetically linked to both brain aging and DAT.
• The presence of lobar cerebral hemorrhage in the elderly and DAT patients suggests an association with CAA.