Plasma proteomic profiles of Alzheimer's disease and neurodegeneration in African cohorts.

Alzheimer's disease and related dementia (ADRD) represents a growing public health burden, especially in low- and middle-income countries. Yet, most studies focus on Non-Hispanic white (NHW) populations from high-income countries. This study investigates plasma proteomic signatures associated with amyloid pathology in African populations. Nigerian older adults from the VALIANT study and participants from a Tanzanian study, with available biomarker quantification in plasma are employed. For proteomic comparison, participants from the Canadian TRIAD cohort are included, capturing a distinct population. Here, we show that multiple proteins are differentially abundant in the plasma of p-tau217-positive individuals and in the different cognitive groups, with findings largely consistent amongst African cohorts. Comorbidities are significantly associated with protein levels and differences in plasma biomarkers levels are found between sexes. Lastly, VALIANT and TRIAD show both shared and unique protein profiles in relation to amyloid-pathology. These findings support the utility of fluid biomarkers in ADRD in African populations.