Performance of Fully-Automated High-Throughput Plasma Biomarker Assays for Alzheimer’s Disease in Amnestic Mild Cognitive Impairment Subjects

Abstract

Introduction

Novel plasma biomarkers are promising for identifying Alzheimer’s disease (AD) pathological processes in vivo, but most currently employed assays have limitations precluding widespread use.

Methods

CSF and plasma samples were collected from seventy amnestic mild cognitive impairment (aMCI) subjects, stratified as A+ and A−. CSF Aβ40, Aβ42, p-tau181 and t-tau and plasma Aβ40, Aβ42 and p-tau181 quantification were conducted using the Lumipulse G assays (Fujirebio), to evaluate the diagnostic performance of plasma biomarkers and assess their associations with CSF biomarkers.

Results

All plasma biomarkers except Aβ40 showed a very good accuracy in distinguishing A+ aMCI from A− aMCI, Aβ42/p-tau181 ratio being the most accurate (AUC 0.895, sensitivity 95.1%, specificity 82.8%). Plasma biomarkers levels were significantly associated with CSF biomarkers concentration.

Discussion

High-throughput and fully-automated plasma assays could be helpful in discriminating with high accuracy between aMCI in the AD continuum and aMCI unlikely due to AD in clinical settings.