title: Plasma β amyloid and the risk of Alzheimer's disease in Down syndrome.
abstract: Extracellular deposition of amyloid beta peptide (Aβ) has been implicated as a critical step in the pathogenesis of Alzheimer's disease (AD). In Down syndrome (DS), Alzheimer's disease is assumed to be caused by the triplication and overexpression of the gene for amyloid precursor protein (APP), located on chromosome 21. Plasma concentrations of Aβ1-40 and Aβ1-42 were determined in a population based study of 506 persons with DS, who were screened annually for dementia. We used Cox proportional hazards models to determine the risk of dementia. Demented persons with DS have a significantly higher plasma Aβ1-40 concentration than the nondemented (p = 0.05). Those with the highest concentrations of Aβ1-40 and Aβ1-42 have a higher risk to develop dementia. The risk to develop dementia during follow-up (mean 4.7 years) increased to 2.56 (95% confidence interval, 1.39-4.71) for Aβ1-42 and 2.16 (95% confidence interval, 1.14-4.10) for Aβ1-40. High plasma concentration of plasma Aβ1-40 and Aβ1-42 are determinants of the risk of dementia in persons with DS.
authors.affiliation: Dichterbij, Center for the Intellectually Disabled, Gennep, The Netherlands. a.coppus@erasmusmc.nl
authors.forename: Antonia M W
authors.initials: AM
authors.lastname: Coppus
authors.forename: Maaike
authors.initials: M
authors.lastname: Schuur
authors.forename: Jeanet
authors.initials: J
authors.lastname: Vergeer
authors.forename: A Cecile J W
authors.initials: AC
authors.lastname: Janssens
authors.forename: Ben A
authors.initials: BA
authors.lastname: Oostra
authors.forename: Marcel M
authors.initials: MM
authors.lastname: Verbeek
authors.forename: Cornelia M
authors.initials: CM
authors.lastname: van Duijn
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000097:blood* / Q000453:epidemiology*; D016229:Amyloid beta-Peptides / Q000097:blood*; D018672:Community Health Planning; D004185:Disability Evaluation; D004314:Down Syndrome / Q000097:blood* / Q000453:epidemiology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D038801:International Classification of Diseases; D008297:Male; D008875:Middle Aged; D009426:Netherlands; D010446:Peptide Fragments / Q000097:blood; D016016:Proportional Hazards Models; D012189:Retrospective Studies
chemical_list: D016229:Amyloid beta-Peptides; D010446:Peptide Fragments; C078592:amyloid beta-protein (1-40); C075222:amyloid beta-protein (1-42)