Prognostic Value of A/T/N Biomarkers: Comparing Plasma and Imaging Modalities in Alzheimer Disease.

Background: Alzheimer disease (AD) is characterized by amyloid-β plaques (A), tau tangles (T), and neurodegeneration (N), collectively defining the ATN framework. While imaging biomarkers are well-established, the prognostic value of plasma biomarkers in predicting cognitive decline remains underexplored. This study compares plasma and imaging A/T/N biomarkers in predicting cognitive decline and evaluate the impact of combining biomarkers across modalities.

Integrating MRI Volume and Plasma p-Tau217 for Amyloid Risk Stratification in Early-Stage Alzheimer Disease.

Background And Objectives: Identifying β-amyloid (Aβ) positivity is crucial for selecting candidates for Aβ-targeted therapies in early-stage Alzheimer disease (AD). While Aβ PET is accurate, its high cost limits routine use. Plasma p-tau217 testing offers a less invasive option but also incurs additional costs.

Integrating visual assessments and quantification methods for tau PET staging.

Introduction: We compared visual assessments and quantification methods for tau positron emission tomography (PET) staging and evaluated plasma biomarkers and cognitive trajectories across amyloid and tau (AT) staging.

Methods: Tau PET scans from 289 Korea-Registries to Overcome Dementia and Accelerate Dementia Research (K-ROAD) participants were analyzed visually and quantitatively, with validation in the Alzheimer's Disease Neuroimaging Initiative (ADNI) cohort (n = 870). Plasma biomarkers and cognitive measures were evaluated across AT stages.

Tailoring thresholds for interpreting plasma p-tau217 levels.

Background: Plasma phosphorylated tau (p-tau) 217 test has emerged as a minimally invasive and accessible alternative to positron emission tomography imaging and cerebrospinal fluid analysis for Alzheimer's disease (AD) diagnostics. However, the diagnostic performance of p-tau217 across diverse cognitive and demographic subgroups remains underexplored. This multicentre cross-sectional study aimed to assess the diagnostic utility of plasma p-tau217 using a double cut-off approach in a large, diverse cohort, focusing on subgroup analyses based on cognitive status, age, sex, body mass index and ε4 carrier status.

Reproducibility of Plasma Biomarker Measurements Across Laboratories: Insights Into ptau217, GFAP, and NfL.

Background And Purpose: Plasma biomarkers, including phosphorylated tau (ptau217), glial fibrillary acidic protein (GFAP), and neurofilament light chain (NfL), are promising tools for detecting Alzheimer's disease (AD) pathology. However, cross-laboratory reproducibility remains a challenge, even when using identical analytical platforms such as single-molecule array (Simoa). This study aimed to compare plasma biomarker measurements (ptau217, GFAP, and NfL) between 2 laboratories, the University of Gothenburg (UGOT) and DNAlink, and evaluate their associations with amyloid positron emission tomography (PET) imaging.

Comparison of accumulation rates of beta-amyloid tracers and their relationship with cognitive changes.

We aimed to compare amyloid-β (Aβ) accumulation rates between different tracers and investigate whether the relationship between changes in Aβ uptake and cognitive decline varies depending on tracer type. Two cohorts were analyzed: (1) a head-to-head longitudinal cohort using F-Florbetaben (FBB) and F-Flutemetamol (FMM) tracers (n = 13), and (2) separate longitudinal cohorts for each tracer (n = 174 for both FMM and FBB), matched by propensity score. Aβ uptake was measured using regional direct comparison of Centiloid (rdcCL) values.