title: White matter degeneration in subjective cognitive decline: a diffusion tensor imaging study.
abstract: Subjective cognitive decline (SCD) may be an at-risk stage of Alzheimer's disease (AD) occurring prior to amnestic mild cognitive impairment (aMCI). To examine white matter (WM) defects in SCD, diffusion images from 27 SCD (age=65.3±8.0), 35 aMCI (age=69.2±8.6) and 25 AD patients (age=68.3±9.4) and 37 normal controls (NC) (age=65.1±6.8) were compared using Tract-Based Spatial Statistics (TBSS). WM impairments common to the three patient groups were extracted, and fractional anisotropy (FA) values were averaged in each group. As compared to NC subjects, SCD patients displayed widespread WM alterations represented by decreased FA (p<0.05), increased mean diffusivity (MD; p<0.05), and increased radial diffusivity (RD; p<0.05). In addition, localized WM alterations showed increased axial diffusivity (AxD; p<0.05) similar to what was observed in aMCI and AD patients (p<0.05). In the shared WM impairment tracts, SCD patients had FA values between the NC group and the other two patient groups. In the NC and SCD groups, the AVLT-delayed recall score correlated with higher AxD (r=-0.333, p=0.045), MD (r=-0.351, p=0.03) and RD (r=-0.353, p=0.025). In both the aMCI and AD groups the diffusion parameters were highly correlated with cognitive scores. Our study suggests that SCD patients present with widespread WM changes, which may contribute to the early memory decline they experience.
authors.affiliation: Department of Neurology, XuanWu Hospital of Capital Medical University, Beijing, 100053, China.
authors.forename: Xuan-Yu
authors.initials: XY
authors.lastname: Li
authors.affiliation: School of Mechanical, Electrical & Information Engineering, Shandong University, Weihai, Shandong Province, 264209, China.
authors.forename: Zhen-Chao
authors.initials: ZC
authors.lastname: Tang
authors.affiliation: Department of Neurology, XuanWu Hospital of Capital Medical University, Beijing, 100053, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Sun
authors.affiliation: Key Laboratory of Molecular Imaging, Institute of Automation, Chinese Academy of Sciences, Beijing, 100190, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Tian
authors.affiliation: Key Laboratory of Molecular Imaging, Institute of Automation, Chinese Academy of Sciences, Beijing, 100190, China.
authors.forename: Zhen-Yu
authors.initials: ZY
authors.lastname: Liu
authors.affiliation: Department of Neurology, XuanWu Hospital of Capital Medical University, Beijing, 100053, China.|Center of Alzheimer's Disease, Beijing Institute for Brain Disorders, Beijing, 100053, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Han
mesh_terms: D000368:Aged; D016880:Anisotropy; D060825:Cognitive Dysfunction / Q000000981:diagnostic imaging / Q000473:pathology* / Q000523:psychology; D056324:Diffusion Tensor Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D066127:White Matter / Q000000981:diagnostic imaging / Q000473:pathology*
keywords: diffusion tensor imaging; preclinical Alzheimer’s disease; subjective cognitive decline; tract-based spatial statistics; white matter