Validation of AD-CSF-Index in Chinese patients with Alzheimer's disease and nondemented controls.

Abstract

Cerebrospinal fluid (CSF) biomarkers of Alzheimer's disease (AD), especially Aβ42/t-tau and Aβ42/p-tau, showed high diagnostic sensitivities and specificities. But significant interassay and interlaboratory variabilities hinder the widespread clinical applications of CSF biomarkers. The objective of this study was to validate the diagnostic accuracy of AD-CSF-Index in our local Chinese patients with AD compared to nondemented controls. A total of 36 patients, which included 24 patients with AD and 12 nondemented controls, were recruited. Chinese patients with AD showed higher mean AD-CSF-Indices than nondemented controls (AD = 1.25-1.3, normal = 0.62-0.63; P < .001). The AD-CSF-indices have a high sensitivity and specificity of 86.4% to 90.9% and 83.3%, respectively, in differentiating patients with AD from nondemented controls. After selecting the patients with "pure AD" and "pure normal" controls, the AD-CSF-indices have a high sensitivity and specificity of 94.1% and 90%, respectively, in differentiating patients with AD from nondemented controls. Most importantly, our AD-CSF-indices cutoff was highly similar to that reported in Western studies.