Ethnic Differences in Dementia Revealed by Multimodal Imaging

Inflammatory genes are known to only show in African Americans and non-Hispanic Whites. The objective of this study was to observe the correlation from the obtained data of the prevalence of the APOE ε4 genotype. We examined cerebral free-water, a marker of neuroinflammation, hippocampal volume, and volume of white-matter hyperintensities in African Americans (AA) and non-Hispanic Whites who were categorized in groups based on whether they had APOE ε4 allele or not. AA had lower prevalence of APOE e4 genotype than non-Hispanic Whites. AA groups have a slightly higher hippocampal volume compared to the Non-Hispanic White (NHW) groups. African Americans also reported increased white-matter hyperintensities and cerebral free-water. Hippocampal atrophy is associated with Alzheimer's disease, this might suggest that the AA groups have a lower risk of Alzheimer's, although further research is needed to confirm this relationship. Lastly, our findings also suggest other potential socioeconomic factors that could contribute to increased incidence of dementia among AA and potential resilience factors early in the course of Alzheimer’s disease process.