The association of blood-based biomarkers of neuropathology with cognitive performance and incident dementia in a diverse, nationally-representative sample of US adults

There are currently limited data on blood-based biomarkers of neuropathology as predictors of cognitive performance and incident dementia in diverse, population-based cohort studies.We used data from the Health and Retirement Study (n-=4,214) to examine the association between blood-based biomarkers of neuropathology and cognitive function, as well as their association with incident dementia and mortality 4 years after measurement. Mean levels of A <b>β</b> -42/A <b>β</b> -40 were similar across race/ethnic groups and age groups in this US population-representative sample where selection effects have been minimized. Average NfL was higher among non-Hispanic blacks and Hispanics; GFAP was higher among non-Hispanic blacks as compared to non-Hispanic whites. In a model that included all four biomarkers, NfL remained significantly related to cognitive performance in the total sample and in each race/ethnic group. NfL was associated with incident dementia 6 years after measurement in the total sample. A <b>β</b> -42/A <b>β</b> -40 ratio was predictive of 6-year incident dementia among those with at least one APOE e4 allele.