Derivation of cutoffs for the Elecsys® amyloid β (1–42) assay in Alzheimer's disease

Alzheimer’s & Dementia: Diagnosis, Assessment & Disease Monitoring

Michael J. Pontecorvo¹  Leslie M. Shaw²  Michal Figurski²  John Q. Trojanowski²  Magdalena Korecka²  Leona Fields²  Teresa Waligorska²  Eric R. Siemers³  Scott W. Andersen³  Jayne A. Talbot³  D. Richard Lachno⁴  Robert A. Dean⁵  Simone Wahl⁶  Udo Eichenlaub⁶  Marian Quan⁷ 

[1] Clinical DevelopmentAvid RadiopharmaceuticalsPhiladelphiaPAUSA;Department of Pathology and Laboratory MedicinePerelman School of Medicine, University of PennsylvaniaPhiladelphiaPAUSA;Eli Lilly and CompanyIndianapolisINUSA;Eli Lilly and CompanyWindleshamSurreyUK;Indiana University School of MedicineIndianapolisINUSA;Roche Diagnostics GmbHBavariaGermany;Roche DiagnosticsIndianapolisINUSA;

关键词: Alzheimer's disease;    Biomarkers;    Immunoassay;    Amyloid β;    Cerebrospinal fluid;    Method comparison;   

DOI  :  10.1016/j.dadm.2018.07.002

来源: DOAJ

【 摘 要 】

Abstract Introduction An Elecsys® Amyloid β (Aβ [1–42]) immunoassay cutoff for classification of patients with Alzheimer's disease was investigated. Methods Cerebrospinal fluid samples collected from patients with mild‐to‐moderate Alzheimer's disease were analyzed by Elecsys® immunoassays: (1) Aβ (1–42), (2) total tau, and (3) phosphorylated tau. Cutoffs (Aβ [1–42] and ratios with tau) were estimated by method comparison between AlzBio3 (n = 206), mixture modeling (n = 216), and concordance with florbetapir F 18 imaging‐based classification (n = 75). Results A 1065‐pg/mL (95% confidence interval: 985–1153) Elecsys® Aβ (1–42) cutoff provided 94% overall percentage agreement with AlzBio3. Comparable cutoff estimates (95% confidence interval) were derived from mixture modeling (equally weighted: 1017 [949–1205] pg/mL; prevalence weighted: 1172 [1081–1344] pg/mL) and concordance with florbetapir F 18 imaging (visual read: 1198 [998–1591] pg/mL; automated: 1198 [1051–1638] pg/mL). Discussion Based on three approaches, a 1100‐pg/mL Elecsys® Aβ (1–42) cutoff is suitable for clinical trials with similar populations and preanalytical handling.

【 授权许可】

Unknown