TY - JOUR
T1 - Plasma amyloid-β as a function of age, level of intellectual disability, and presence of dementia in down syndrome
AU - Head, Elizabeth
AU - Doran, Eric
AU - Nistor, Mihaela
AU - Hill, Maryann
AU - Schmitt, Frederick A.
AU - Haier, Richard J.
AU - Lott, Ira T.
PY - 2011
Y1 - 2011
N2 - Adults with Down syndrome (DS) are at risk for developing Alzheimer's disease (AD). While plasma amyloid-β (Aβ) is known to be elevated in DS, its relationship to cognitive functioning is unknown. To assess this relationship, samples from two groups of subjects were used. In the first group, nondemented adults with DS were compared to: 1) a group of young and old individuals without DS and 2) to a group of patients with AD. Compared to these controls, there were significantly higher levels of plasma Aβ in nondemented adults with DS while AD patients showed lower levels of plasma Aβ. A larger second group included demented and nondemented adults with DS, in order to test the hypothesis that plasma Aβ may vary as a function of dementia and Apolipoprotein E (ApoE) genotype. Plasma Aβ levels alone did not dissociate DS adults with and without dementia. However, in demented adults with DS, ApoE4 was associated with higher Aβ40 but not Aβ42. After controlling for level of intellectual disability (mild, moderate, severe) and the presence or absence of dementia, there was an improved prediction of neuropsychological scores by plasma Aβ. In summary, plasma Aβ can help predict cognitive function in adults with DS independently of the presence or absence of dementia.
AB - Adults with Down syndrome (DS) are at risk for developing Alzheimer's disease (AD). While plasma amyloid-β (Aβ) is known to be elevated in DS, its relationship to cognitive functioning is unknown. To assess this relationship, samples from two groups of subjects were used. In the first group, nondemented adults with DS were compared to: 1) a group of young and old individuals without DS and 2) to a group of patients with AD. Compared to these controls, there were significantly higher levels of plasma Aβ in nondemented adults with DS while AD patients showed lower levels of plasma Aβ. A larger second group included demented and nondemented adults with DS, in order to test the hypothesis that plasma Aβ may vary as a function of dementia and Apolipoprotein E (ApoE) genotype. Plasma Aβ levels alone did not dissociate DS adults with and without dementia. However, in demented adults with DS, ApoE4 was associated with higher Aβ40 but not Aβ42. After controlling for level of intellectual disability (mild, moderate, severe) and the presence or absence of dementia, there was an improved prediction of neuropsychological scores by plasma Aβ. In summary, plasma Aβ can help predict cognitive function in adults with DS independently of the presence or absence of dementia.
KW - Apolipoprotein E
KW - cognition
KW - mental status
KW - neuropsychology
KW - trisomy 21
UR - http://www.scopus.com/inward/record.url?scp=79951873364&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=79951873364&partnerID=8YFLogxK
U2 - 10.3233/JAD-2010-101335
DO - 10.3233/JAD-2010-101335
M3 - Article
C2 - 21116050
AN - SCOPUS:79951873364
SN - 1387-2877
VL - 23
SP - 399
EP - 409
JO - Journal of Alzheimer's Disease
JF - Journal of Alzheimer's Disease
IS - 3
ER -