title: Plasma amyloid-β levels and prognosis in incident dementia cases of the 3-City Study.
abstract: Studies of plasma amyloid-β (Aβ) levels as potential biomarkers for incident Alzheimer's disease (AD) have yielded contradictory results. We explored the associations between plasma Aβ(40), Aβ(42), and truncated Aβ levels, and prognosis of dementia in participants of the prospective 3-City Study. 120 aged individuals diagnosed with 2-year incident dementia were followed up for seven years. The associations between Aβ plasma levels and baseline cognitive score, cognitive decline, and death were examined. A higher level of baseline plasma Aβ was associated with worse cognitive status two years prior to incident dementia diagnosis. In incident AD patients, the association was only significant for Aβ(40) and Aβ(n-42). In the fast cognitive decliners group, especially in AD cases, a higher level of 5 pg/ml of baseline Aβ(42), Aβ(n-42), Aβ(n-42)/Aβ(n-40), and Aβ(42)/Aβ(40) ratios were associated with a lower risk of fast cognitive decline based on the Isaacs Set Test score. There was no association between peptide levels and mortality in demented subjects. When assayed at prodromal stage, plasma Aβ levels may be potentially useful markers of fast cognitive decline in individuals who subsequently become demented.
authors.affiliation: Department of Neurology, Centre Mémoire Ressources Recherche Languedoc-Roussillon, CHRU Gui de Chauliac Hospital, Montpellier, France. a-gabelle@chu-montpellier.fr
authors.forename: Audrey
authors.initials: A
authors.lastname: Gabelle
authors.forename: Florence
authors.initials: F
authors.lastname: Richard
authors.forename: Laure-Anne
authors.initials: LA
authors.lastname: Gutierrez
authors.forename: Susanna
authors.initials: S
authors.lastname: Schraen
authors.forename: Fleur
authors.initials: F
authors.lastname: Delva
authors.forename: Olivier
authors.initials: O
authors.lastname: Rouaud
authors.forename: Luc
authors.initials: L
authors.lastname: Buée
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Dartigues
authors.forename: Jacques
authors.initials: J
authors.lastname: Touchon
authors.forename: Jean-Charles
authors.initials: JC
authors.lastname: Lambert
authors.forename: Claudine
authors.initials: C
authors.lastname: Berr
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000097:blood* / Q000401:mortality*; D016229:Amyloid beta-Peptides / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D060825:Cognitive Dysfunction / Q000097:blood* / Q000401:mortality*; D003704:Dementia / Q000097:blood / Q000401:mortality; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D005602:France / Q000453:epidemiology; D006801:Humans; D015994:Incidence; D008297:Male; D015999:Multivariate Analysis; D011379:Prognosis; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012307:Risk Factors; D014505:Urban Population / Q000706:statistics & numerical data
chemical_list: D016229:Amyloid beta-Peptides; D015415:Biomarkers