A comparison of cerebral small vessel disease severity between autopsy cohorts in the northeast of England and Sacramento County in California, USA

Abstract

AbstractBackgroundCerebral small vessel disease (SVD) encompasses progressive fibrosis/hyalinosis of the small arteries and arterioles of the white matter (WM) resulting in ischemic WM damage. Few studies have compared SVD between different cohorts. Using a sclerotic index (SI) measurement, we quantitatively assessed vessel wall fibrosis in the frontal and parietal WM of human brains donated to brain banks in the UK and the USA.Method64 cases from the University of California Davis (UCD) Alzheimer’s Disease Centre Biorepository and 55 cases from the Newcastle Brain and Tissue resource (NBTR) were included. Cases were neuropathological diagnosed as controls (UCD n=18; NBTR n=25), intermediate Alzheimer’s disease (AD) neuropathologic change (UCD n=13; NBTR n=4), and definite AD (UCD n=33; NBTR n = 26). In the UCD cohort, 49 identified racially as White, 9 as Black African American, 3 as Chinese and 1 as Indian Asian. All cases from the NBTR identified racially as White. Using H&E sections, images of approximately eight arteries/arterioles from the frontal and parietal WM were captured and SI assessment performed. Mean SI score was calculated per region, per cases.ResultNo intergroup differences in age were observed and age was not associated with SI score in either cohort. In the UCD cohort, race was not associated with neuropathological diagnosis (Chi‐sq = 8.39, p>0.211) and no differences were seen in SI scores between White and Black African Americans (p>0.69). Intergroup comparisons revealed that SI scores in both WM regions were significantly higher in the overall UCD cohort compared to the overall NBTR cohort (p>0.006) and this was consistent across controls (frontal p=0.0001; parietal p=0.045), intermediate AD neuropathological change (p=0.001), and AD (frontal p=0.001) cases.ConclusionSVD‐associated vessel occlusion is more severe in the USA cohort from Sacramento compared to the UK cohort from Newcastle. This may reflect differences in cardiovascular disease and lifestyle of individuals enrolled in the two brain donation programmes.