title: Association of plasma β-amyloid with MRI markers of structural brain aging the 3-City Dijon study.
abstract: Cerebral β-amyloid (Aβ) deposition and atrophy are central features of Alzheimer disease. Studies of Alzheimer disease biomarkers have largely focused on Aβ in cerebrospinal fluid (CSF), and there is uncertainty as to what plasma Aβ may be a marker. We examined the association of Aβ levels in the plasma with magnetic resonance imaging (MRI)-markers of brain aging, including longitudinal changes in global and regional brain volumes, in dementia-free persons. We studied 1530 participants of the Three-City-Dijon cohort, aged 65-80 years. Plasma Aβ measurement and magnetic resonance imaging were performed at baseline and after a 4-year follow up. Total brain, gray matter, and hippocampal volume were estimated using voxel-based morphometry, and annualized change in brain volumes was calculated. Increased plasma Aβ1-40 was associated with lower baseline hippocampal volume. Although baseline plasma Aβ levels were not associated with longitudinal change in brain volumes, consistently high plasma Aβ1-40 levels were associated with faster total brain atrophy and consistently low plasma Aβ1-42/Aβ1-40 ratio, with increased total brain atrophy and gray matter atrophy. In dementia-free older adults, high plasma Aβ1-40 and low plasma Aβ1-42/Aβ1-40 ratio were associated with smaller hippocampal volume and accelerated global and regional brain atrophy respectively.
authors.affiliation: INSERM U897, University of Bordeaux, Bordeaux, France. Electronic address: sara.kaffashian@inserm.fr.
authors.forename: Sara
authors.initials: S
authors.lastname: Kaffashian
authors.affiliation: INSERM U897, University of Bordeaux, Bordeaux, France.
authors.forename: Christophe
authors.initials: C
authors.lastname: Tzourio
authors.affiliation: INSERM U897, University of Bordeaux, Bordeaux, France.
authors.forename: Aïcha
authors.initials: A
authors.lastname: Soumaré
authors.affiliation: INSERM U897, University of Bordeaux, Bordeaux, France.
authors.forename: Carole
authors.initials: C
authors.lastname: Dufouil
authors.affiliation: CNRS-CEA UMR5296, University of Bordeaux, Bordeaux, France.
authors.forename: Bernard
authors.initials: B
authors.lastname: Mazoyer
authors.affiliation: CHRU de Lille, Lille, France; INSERM U837, Lille, France.
authors.forename: Susanna
authors.initials: S
authors.lastname: Schraen-Maschke
authors.affiliation: CHRU de Lille, Lille, France; INSERM U837, Lille, France.
authors.forename: Luc
authors.initials: L
authors.lastname: Buée
authors.affiliation: INSERM U897, University of Bordeaux, Bordeaux, France; Department of Neurology, Bordeaux University Hospital, Bordeaux, France; Department of Neurology, Framingham Heart Study, Boston University School of Medicine, Boston MA, USA.
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Debette
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000097:blood* / Q000473:pathology*; D000544:Alzheimer Disease / Q000097:blood / Q000175:diagnosis* / Q000209:etiology / Q000473:pathology; D016229:Amyloid beta-Peptides / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D001921:Brain / Q000473:pathology*; D005260:Female; D005500:Follow-Up Studies; D006624:Hippocampus / Q000473:pathology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009929:Organ Size; D010446:Peptide Fragments / Q000097:blood
chemical_list: D016229:Amyloid beta-Peptides; D015415:Biomarkers; D010446:Peptide Fragments; C078592:amyloid beta-protein (1-40); C075222:amyloid beta-protein (1-42)
keywords: Alzheimer disease; Amyloid; Biomarkers; Brain atrophy; Brain volume; Hippocampal volume; Plasma