Plasma Phosphorylated Tau 217 as a Discriminative Biomarker for Cerebral Amyloid Angiopathy
Journal
European Journal of Neurology
Journal Volume
32
Journal Issue
2
Start Page
e70066
ISSN
1351-5101
Date Issued
2025-02
Author(s)
Hsieh, Pei-Feng
Tsai, Ya-Chin
DOI
10.1111/ene.70066
Abstract
Background: Blood-based biomarkers may offer a non-invasive approach to diagnose cerebral amyloid angiopathy (CAA), especially in early-stage. We evaluated the ability of plasma phosphorylated tau-217 (p-tau 217) to differentiate CAA from Alzheimer's disease (AD) and deep perforator arteriopathy (DPA). Methods: Patients with AD (age 73.7 ± 8.1 years), probable CAA (74.8 ± 6.9 years), or DPA (66.1 ± 10.4 years) were enrolled from memory and stroke clinics at a medical center in Taiwan. All participants received amyloid and tau PET scans. Plasma biomarkers were measured via a SIMOA immunoassay platform. The diagnostic utility of p-tau 217 was assessed using ROC analyses and the Youden cutoff. Associations between plasma p-tau 217 and neuroimaging variables in CAA were explored. Results: Patients with CAA had lower plasma p-tau 217 (0.69 ± 0.76 vs. 1.28 ± 0.97 pg/mL, p < 0.001) and a lower p-tau 217/Aβ40 ratio (0.003 ± 0.002 vs. 0.006 ± 0.003, p < 0.001) than the AD group but higher levels than the DPA group (p-tau 217, 0.27 ± 0.13 pg/mL, p = 0.001; p-tau 217/Aβ40, 0.001 ± 0.0005, p < 0.001), although adjustment attenuated the difference in p-tau 217 between CAA and DPA. Plasma Aβ40, Aβ42, and Aβ40/Aβ42 were not significantly different between groups. Plasma p-tau 217 had moderate to good diagnostic utility to differentiate CAA vs. AD (sensitivity, 64.4%; specificity, 89.5%; AUC, 0.809) and CAA vs. DPA (sensitivity, 67.8%; specificity, 100%; AUC, 0.855). In CAA, p-tau 217 significantly correlated with the severity of CAA, amyloid PET signal intensity, and lobar microbleed count (p < 0.001). Conclusions: Plasma p-tau 217 may represent a non-invasive biomarker for distinguishing cerebral amyloid angiopathy (CAA) from other conditions, including AD and DPA.
Subjects
Alzheimer disease
cerebral amyloid angiopathy
cerebral small vessel disease
phosphorylated tau 217
plasma biomarker
SDGs
Publisher
John Wiley and Sons Inc
Description
Article number e70066
Type
journal article