title: Multivariate and univariate neuroimaging biomarkers of Alzheimer's disease.
abstract: We performed univariate and multivariate discriminant analysis of FDG-PET scans to evaluate their ability to identify Alzheimer's disease (AD). FDG-PET scans came from two sources: 17 AD patients and 33 healthy elderly controls were scanned at the University of Michigan; 102 early AD patients and 20 healthy elderly controls were scanned at the Technical University of Munich, Germany. We selected a derivation sample of 20 AD patients and 20 healthy controls matched on age with the remainder divided into 5 replication samples. The sensitivity and specificity of diagnostic AD-markers and threshold criteria from the derivation sample were determined in the replication samples. Although both univariate and multivariate analyses produced markers with high classification accuracy in the derivation sample, the multivariate marker's diagnostic performance in the replication samples was superior. Further, supplementary analysis showed its performance to be unaffected by the loss of key regions. Multivariate measures of AD utilize the covariance structure of imaging data and provide complementary, clinically relevant information that may be superior to univariate measures.
authors.affiliation: Taub Institute, Columbia University Medical Center, New York, NY 10032, USA. ch629@columbia.edu
authors.forename: Christian
authors.initials: C
authors.lastname: Habeck
authors.forename: Norman L
authors.initials: NL
authors.lastname: Foster
authors.forename: Robert
authors.initials: R
authors.lastname: Perneczky
authors.forename: Alexander
authors.initials: A
authors.lastname: Kurz
authors.forename: Panagiotis
authors.initials: P
authors.lastname: Alexopoulos
authors.forename: Robert A
authors.initials: RA
authors.lastname: Koeppe
authors.forename: Alexander
authors.initials: A
authors.lastname: Drzezga
authors.forename: Yaakov
authors.initials: Y
authors.lastname: Stern
mesh_terms: D000368:Aged; D000465:Algorithms; D000544:Alzheimer Disease / Q000000981:diagnostic imaging* / Q000378:metabolism*; D000704:Analysis of Variance; D015415:Biomarkers; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D049268:Positron-Emission Tomography; D025341:Principal Component Analysis; D019275:Radiopharmaceuticals
chemical_list: D015415:Biomarkers; D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18