Plasma P-tau 181, P-tau 217 and Other Blood-Based Alzheimer's Disease Biomarkers in a Multi-Ethnic, Community Study

Introduction. Blood-based Alzheimer's disease (AD) biomarkers provide opportunities for community studies and across ethnic groups. We investigated blood biomarker concentrations in the Washington Heights, Inwood, Columbia Aging Project (WHICAP), a multi-ethnic community study of aging and dementia. Methods. We measured plasma A{beta}40, A{beta}42,T-tau, P-tau181 and P-tau217, and neurofilament light chain (NfL) in 113 autopsied participants, (29% with high AD neuropathological changes) and in 300 clinically evaluated individuals (42% with clinical AD). Receiver operating characteristics were used to evaluate each biomarker. We also investigated biomarkers as predictors of incident clinical AD. Results. P-tau181, P-tau217 and NfL concentrations were elevated in pathologically and clinically diagnosed AD. Decreased A{beta}42/A{beta}40 ratio and increased P-tau217 and P-tau181 were associated with subsequent AD diagnosis. Discussion. Blood-based AD biomarker concentrations are associated with pathological and clinical diagnoses and can predict future development of clinical AD, providing evidence that they can be incorporated into multi-ethnic, community-based studies.