Basic Science and Pathogenesis.

Background: The atherosclerotic plaque in carotid arteries has been associated with dementia. Clinic radiological studies in older adults suggest that the composition of atherosclerotic plaque in the carotid artery can predict vascular dementia (VD) or mixed dementia. The proposed study aims to assess components of atherosclerotic plaques in the carotid arteries, particularly concerning cerebrovascular lesions using racially diverse autopsy samples.

Method: We used data from the Biobank for Aging Studies at the University of São Paulo Medical School. We included participants aged 50 years or older at the time of death with a post-mortem interval of less than 24 hours and a next of kin who had at least weekly contact with the deceased (n = 505). The plaque composition was evaluated using the Atherosclerotic Plaque Analyzer (APA) software. Cerebrovascular lesions included lacunar infarcts, hyaline arteriolosclerosis, and cerebral amyloid angiopathy evaluated microscopically in 13 samples areas. Logistic regression models adjusted for sociodemographic and clinical variables were used to investigate the associations between plaque composition and cerebrovascular deceased.

Results: After the exclusions for missing data, 193 participants were included (mean age 79.4±10.0 years, 51.3% were women, and 61% were White) (Table 1). A higher percentage of lipid deposition in the plaque was associated with higher odds of cerebral amyloid angiopathy (OR = 1.01, 95% CI = 1.03; 1.27, p = 0.007). We found no association between the other plaque components and cerebrovascular diseases (Table 3).

Conclusion: In an autopsy study, the deposition of lipids in the carotid atheroma plaque was associated with cerebral amyloid angiopathy. Further autopsy studies in larger samples are needed to confirm our findings.