%A JR Chong %A NJ Ashton %A TK Karikari %A T Tanaka %A FN Saridin %A A Reilhac %A EG Robins %A Y-H Nai %A H Vrooman %A S Hilal %A H Zetterberg %A K Blennow %A MKP Lai %A CP Chen %V 17 %T Plasma Pâ€tau181 to Aβ42 ratio is associated with brain amyloid burden and hippocampal atrophy in an Asian cohort of Alzheimer's disease patients with concomitant cerebrovascular disease %N 10 %P 1649-1662 %D 2021 %L discovery10126218 %J Alzheimer's & Dementia %K Alzheimer's disease, amyloid beta, biomarkers, cerebrovascular disease, non-Alzheimer's pathophysiology, phosphorylated tau, plasma %X INTRODUCTION: There is increasing evidence that phosphorylated tau (P-tau181) is a specific biomarker for Alzheimer's disease (AD) pathology, but its potential utility in non-White patient cohorts and patients with concomitant cerebrovascular disease (CeVD) is unknown. METHODS: Single molecule array (Simoa) measurements of plasma P-tau181, total tau, amyloid beta (Aβ)40 and Aβ42, as well as derived ratios were correlated with neuroimaging modalities indicating brain amyloid (Aβ+), hippocampal atrophy, and CeVD in a Singapore-based cohort of non-cognitively impaired (NCI; n = 43), cognitively impaired no dementia (CIND; n = 91), AD (n = 44), and vascular dementia (VaD; n = 22) subjects. RESULTS: P-tau181/Aβ42 ratio showed the highest area under the curve (AUC) for Aβ+ (AUC = 0.889) and for discriminating between AD Aβ+ and VaD Aβ- subjects (AUC = 0.903). In addition, P-tau181/Aβ42 ratio was associated with hippocampal atrophy. None of the biomarkers was associated with CeVD. DISCUSSION: Plasma P-tau181/Aβ42 ratio may be a noninvasive means of identifying AD with elevated brain amyloid in populations with concomitant CeVD. %C United States %O This version is the author accepted manuscript. For information on re-use, please refer to the publisher’s terms and conditions.