Cerebral amyloid angiopathy (CAA) is frequent in patients with Alzheimer's disease while its prevalence in different populations is variable. We investigated the prevalence and severity of CAA in a very elderly Finnish population.
Neuropathological investigation was performed on 306 subjects from the population-based Vantaa 85+ Study (253 women, 53 men, mean age at death 92.3 years). The presence of CAA was analysed in six brain regions by using Congo red and immunohistochemistry with an antibody against amyloid beta peptide. The severity of CAA was assessed by counting the percentage of the CAA-positive blood vessels.
In total, 69.6% of the participants (170 women, 43 men) had CAA, with median severity of 1.0%, inter-quartile range (IQR) 0-5.4% and range 0-72.7%. CAA was more prevalent (81.1% vs. 67.2%; P = 0.046) and severe (median 2.7%, IQR 0.4-7.5%, range 0-72.7%) in the men than in the women (median 1.0%, IQR 0-4.6%, range 0-52.8%; P = 0.004). Parietal lobe showed the highest prevalence (57.8%) whereas the severity was highest (median 1.0%, IQR 0-6.0%, range 0-77%) in the frontal lobe. Prevalence of CAA in the six regions was variable, but the severity indices between those regions correlated highly (P