Despite a smaller sample size, Hispanics demonstrated longer disease duration with Alzheimer disease (AD), but not greater lifespan, according to a recent study. Furthermore, neuropathologic differences across ethnoracial groups supported differences in tau pathology distribution and coexisting hippocampal sclerosis, which may impact biomarker studies. A retrospective study was conducted in the FLorida Autopsied Multi-Ethnic cohort on 1,625 AD cases, including decedents who self-reported as Hispanic/Latino (n=67), black/African American (n=19), and white/European American (n=1,539). Researchers found:
- Hispanic decedents had a higher frequency of family history of cognitive impairment (58%), an earlier age at onset (median age 70 years), longer disease duration (median of 12 years), and lower Mini-Mental State Examination (MMSE) proximal to death (median of 4 points) compared with the other ethnoracial groups.
- Black decedents had a lower Braak tangle stage (stage V) and higher frequency of coexisting hippocampal sclerosis (21%); however, only hippocampal sclerosis differences survived adjustment for sex, age at onset, and disease duration.
- Neither Thal amyloid phase nor coexisting Lewy body disease differed across ethnoracial groups.
Santosa OA, Pedraza O, Lucas JA, et al. Ethnoracial differences in Alzheimer's disease from the FLorida Autopsied Multi-Ethnic (FLAME) cohort. [Published online ahead of print February 18, 2019]. Alzheimers Dement. doi:10.1016/j.jalz.2018.12.013.