Plasma p-tau217 is a promising biomarker for detecting incipient AD pathology, but direct comparison of different p-tau217 assays in community-based cohorts are limited. We evaluated two cohorts from southwestern Pennsylvania, USA; the MYHAT-NI study, which included two-year longitudinal follow-up neuroimaging assessments of Aβ, tau, and cortical thickness; and the Human Connectome Project/CoBRA cohort, targeting a 50:50 split of self-identified Black and non-Hispanic White individuals. Plasma p-tau217 was measured using four different assays: Lumipulse, Johnson HCP/CoBRA: n = 234, median age 62 IQR: 52–70, 65% female). All four p-tau217 assays exhibited moderate to strong cross-platform correlations (Spearman correlations of 0.40–0.86), and statistically equivalent AUCs (of 0.84–0.90) for determining Aβ positivity. Our findings show strong equivalent performances of plasma p-tau217 assays to identify amyloid positivity across two highly diverse cohorts of community-dwelling older adults.
Deek et al. (Fri,) studied this question.