title: Frontal white matter integrity in adults with Down syndrome with and without dementia.
abstract: Adults with Down syndrome (DS) are at high risk for developing Alzheimer's disease after the age of 40 years. To detect white matter (WM) changes in the brain linked to dementia, fractional anisotropy (FA) from diffusion tensor imaging was used. We hypothesized that adults with DS without dementia (DS n = 10), DS with dementia (DSAD n = 10) and age matched non-DS subjects (CTL n = 10) would show differential levels of FA and an association with scores from the Brief Praxis Test and the Severe Impairment Battery. WM integrity differences in DS compared with CTL were found predominantly in the frontal lobes. Across all DS adults, poorer Brief Praxis Test performance correlated with reduced FA in the corpus callosum as well as several association tracts, primarily within frontoparietal regions. Our results demonstrate significantly lower WM integrity in DS compared with controls, particularly in the frontal tracts. DS-related WM integrity reductions in a number of tracts were associated with poorer cognition. These preliminary results suggest that late myelinating frontal pathways may be vulnerable to aging in DS.
authors.affiliation: Magnetic Resonance Imaging and Spectroscopy Center, University of Kentucky, Lexington, KY, USA.
authors.forename: David
authors.initials: D
authors.lastname: Powell
authors.affiliation: Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY, USA.
authors.forename: Allison
authors.initials: A
authors.lastname: Caban-Holt
authors.affiliation: Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY, USA; Department of Neurology, University of Kentucky, Lexington, KY, USA.
authors.forename: Gregory
authors.initials: G
authors.lastname: Jicha
authors.affiliation: Department of Neurology, University of Kentucky, Lexington, KY, USA.
authors.forename: William
authors.initials: W
authors.lastname: Robertson
authors.affiliation: Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY, USA.
authors.forename: Roberta
authors.initials: R
authors.lastname: Davis
authors.affiliation: Magnetic Resonance Imaging and Spectroscopy Center, University of Kentucky, Lexington, KY, USA; Department of Anatomy and Neurobiology, University of Kentucky, Lexington, KY, USA.
authors.forename: Brian T
authors.initials: BT
authors.lastname: Gold
authors.affiliation: Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY, USA; Department of Neurology, University of Kentucky, Lexington, KY, USA.
authors.forename: Frederick A
authors.initials: FA
authors.lastname: Schmitt
authors.affiliation: Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY, USA; Department of Molecular and Biomedical Pharmacology, University of Kentucky, Lexington, KY, USA. Electronic address: Elizabeth.head@uky.edu.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Head
mesh_terms: D000328:Adult; D016880:Anisotropy; D003704:Dementia / Q000209:etiology / Q000473:pathology* / Q000523:psychology; D056324:Diffusion Tensor Imaging; D004314:Down Syndrome / Q000150:complications / Q000473:pathology* / Q000523:psychology; D005260:Female; D005625:Frontal Lobe / Q000473:pathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D059906:Neuroimaging; D009483:Neuropsychological Tests
keywords: Aging; BPT; Brief praxis test; DMR; Dementia questionnaire for persons with mental retardation; Diffusion tensor imaging; Fractional anisotropy; SIB; Severe impairment battery; Trisomy 21