Plasma p-tau181, p-tau217, and other blood-based Alzheimer's disease biomarkers in a multi-ethnic, community study.
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ABSTRACT: 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 amyloid beta (Aβ)40, Aβ42, total tau (t-tau), phosphorylated tau (p-tau)181, 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 Aβ42/Aβ40 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.
SUBMITTER: Brickman AM
PROVIDER: S-EPMC8451860 | biostudies-literature |
REPOSITORIES: biostudies-literature
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