Evaluation of plasma p-tau217 for detecting amyloid pathology in a diverse and heterogeneous community-based cohort.

INTRODUCTION

Studies suggest excellent performance of plasma p-tau217 for detecting amyloid pathology, though studies in more diverse populations are needed to validate previously determined cutpoints.

METHODS

Plasma p-tau217 utility for detecting amyloid pathology (Aβ) via amyloid PET (=598) and/or cerebrospinal fluid (CSF; =154) was assessed in a heterogeneous, community-based cohort in the Wake Forest Alzheimer's Disease Research Center (WFADRC). Participants (=598) were 21% Black; 313 cognitive unimpaired (CU), 214 mild cognitive impairment (MCI), and 64 dementia (DEM); 49% prediabetic, 44% hypertensive; 29% overweight/obese; and 64% with mild-to-moderate kidney disease. Gaussian-mixture models, logistic regression, and receiver operating curve analyses were performed.

RESULTS

Plasma p-tau217 was associated with elevated Aβ deposition and accurately classified Aβ-positive participants (PET: AUC: 94%-97%, cutpoint≥.338 pg/mL; CSF: AUC = .84, cutpoint≥.307 pg/mL).

DISCUSSION

Plasma p-tau217 is an accurate indicator of amyloid pathology in a heterogeneous cohort, and superior to other plasma biomarkers assessed. Longitudinal analyses assessing impact of comorbidities on p-tau217 utility for disease progression are underway.