Performance of Fully Automated Plasma Assays as Screening Tests for Alzheimer Disease-Related beta-Amyloid Status

摘要

Key PointsQuestionDo plasma levels of beta -amyloid 42, beta -amyloid 40, and tau detect cerebral beta -amyloid status when measured using fully automated immunoassays? FindingsIn 2 cross-sectional studies, plasma beta -amyloid 42 to beta -amyloid 40 ratio, measured using immunoassay, accurately predicted cerebral beta -amyloid status in all stages of Alzheimer disease in the BioFINDER cohort (n=842) and in an independent validation cohort (n=237). The diagnostic accuracy was further increased by analyzing APOE genotype. MeaningBlood-based beta -amyloid 42 and beta -amyloid 40 ratio together with APOE genotype may be used as prescreening tests in primary care and in clinical Alzheimer disease trials to lower the costs and number of positron emission tomography scans and lumbar punctures.