Clinical and neuropathologic analysis of intracerebral hemorrhage in patients with cerebral amyloid angiopathy

Objective: To evaluate the clinical and histopathological features of elderly patients with subcortical intracerebral hemorrhage (ICH), and to analyze the presence of cerebral amyloid angiopathy (CAA) and Alzheimer's disease (AD) type pathologic changes using amyloid beta (A beta) and tau immunohistochemistry. Patients and methods: We retrospectively analyzed cases satisfying the Boston criteria for CAA among patients with subcortical hemorrhage who underwent surgical removal by craniotomy at our hospital. Surgical specimens were subjected to hematoxylin and eosin (HE) staining as well as immunostaining. Results: A total of 54 patients were included in this study, with a mean age of 74.5 years (range: 72.5-76.5 years, 95% confidence interval [CI]; 51% female). Of these 54 patients, 31 (57%) were hypertensive, 18 (33%) were undergoing antithrombotic therapy, and 12 (22%) had dementia. Strong immunoreactivity for A beta 40 in the cerebral vessels was observed in 30 patients (55.6%), and among these, 27 patients (90%) also showed strong immunoreactivity for A beta 42. Among the 54 patients, 25 (46%) exhibited AD characteristics, including AO-positive senile plaques and AT8-positive neurons. Multivariate analysis revealed that strong A beta 40 immunoreactivity in the cerebral vessels was associated with older patients, females, lack of high blood pressure, and the presence of AT8-positive neurons. Conclusion: CAA patients with strong A beta 40 deposition in the cerebral vessels were associated with subcortical hemorrhage in our cohort. Future studies should investigate the pathomechanism of ICH in individuals with CAA.