title: Increased levels of plasma amyloid-beta are related to cortical thinning and cognitive decline in cognitively normal elderly subjects.
abstract: Plasma levels of circulating amyloid-beta (Aβ) peptides are of particular interest in Alzheimer' disease, but little is known about cognitive and cortical correlates of peripheral Aβ levels in normal aging. Here, we compared cognitive functioning, vascular risk factors, and patterns of cortical thickness between cognitively intact elderly subjects with low (N = 60) and high (N = 60) plasma Aβ levels (cutoffs: 225 pg/mL and 23 pg/mL for Aβ1-40 and Aβ1-42, respectively). Overall, subjects with high Aβ levels showed lower cognitive performance and thinner cortex than those with low Aβ levels. More specifically, subjects with high Aβ1-40 showed bilateral thinning of the prefrontal cortex, poorer objective memory, slower processing speed, and lower nonverbal reasoning skills, whereas subjects with high Aβ1-42 had thinner temporal lobe, poorer everyday memory, and increased levels of homocysteine. Overall, these results suggest that high plasma Aβ levels in normal elderly subjects are associated with subclinical markers of vulnerable aging, which may be helpful at predicting different trajectories of aging in cognitively intact older adults.
authors.affiliation: Laboratory of Functional Neuroscience, Spanish Network of Excellence for Research on Neurodegenerative Diseases (CIBERNED), Pablo de Olavide University, Seville, Spain.
authors.forename: Sandra
authors.initials: S
authors.lastname: Llado-Saz
authors.affiliation: Laboratory of Functional Neuroscience, Spanish Network of Excellence for Research on Neurodegenerative Diseases (CIBERNED), Pablo de Olavide University, Seville, Spain.
authors.forename: Mercedes
authors.initials: M
authors.lastname: Atienza
authors.affiliation: Laboratory of Functional Neuroscience, Spanish Network of Excellence for Research on Neurodegenerative Diseases (CIBERNED), Pablo de Olavide University, Seville, Spain. Electronic address: jlcanlor@upo.es.
authors.forename: Jose L
authors.initials: JL
authors.lastname: Cantero
mesh_terms: D000368:Aged; D000375:Aging / Q000097:blood / Q000473:pathology / Q000523:psychology; D000544:Alzheimer Disease / Q000209:etiology / Q000473:pathology / Q000523:psychology; D016229:Amyloid beta-Peptides / Q000097:blood*; D002540:Cerebral Cortex / Q000473:pathology*; D003071:Cognition / Q000502:physiology*; D003072:Cognition Disorders / Q000209:etiology / Q000523:psychology; D005260:Female; D006710:Homocysteine / Q000097:blood; D006801:Humans; D008297:Male; D010446:Peptide Fragments / Q000097:blood; D012307:Risk Factors
chemical_list: D016229:Amyloid beta-Peptides; D010446:Peptide Fragments; C078592:amyloid beta-protein (1-40); C075222:amyloid beta-protein (1-42); D006710:Homocysteine
keywords: Aging; Alzheimer's disease; Cognitive function; Cortical thickness; Homocysteine; Plasma amyloid-beta