title: Disrupted orbitomedial prefrontal limbic network in individuals with later-life depression.
abstract: Depression in old age is an increasing contributor to poor health and accompanying health care costs. Although there is an abundance of literature on later-life depression (LLD), the neural correlates have not been clarified. The aim of this study was to determine whether patients with LLD show abnormal gray matter volume (GMV) and white matter integrity by using multiple image analysis methods.
  
  
  
  The study included 45 patients with LLD and 61 healthy participants who were matched for age, sex, years of education, and vascular risk factors. GMV was examined using voxel-based morphometry, while the white matter integrity was determined by tract-based spatial statistics and tract-specific analysis, which were obtained from high-resolution magnetic resonance images.
  
  
  
  Patients with LLD showed significantly less GMV in the orbitofrontal cortex, anterior cingulate, insula, amygdala, and temporal regions, as well as higher fractional anisotropy in the uncinate fasciculus, compared with healthy participants. Patients with LLD who had reduced orbitofrontal and insular GMV had more severe clinical variables. The reduced orbitofrontal GMV was associated with higher fractional anisotropy in the uncinate fasciculus.
  
  
  
  The effects of medication should also be considered when interpreting the results of this study.
  
  
  
  Our results suggest that regional GMV is linked to white matter integrity of the uncinate fasciculus in the orbitomedial prefrontal limbic network, and the disruption of this network may be involved in the pathophysiology of LLD.
authors.affiliation: Division of Neuropsychiatry, Department of Neuroscience, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi, Japan.
authors.forename: Kenichiro
authors.initials: K
authors.lastname: Harada
authors.affiliation: Division of Neuropsychiatry, Department of Neuroscience, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi, Japan. Electronic address: kmatsuo@yamaguchi-u.ac.jp.
authors.forename: Koji
authors.initials: K
authors.lastname: Matsuo
authors.affiliation: Division of Neuropsychiatry, Department of Neuroscience, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi, Japan; Nagato-ichinomiya Hospital, Shimonoseki, Yamaguchi, Japan.
authors.forename: Mami
authors.initials: M
authors.lastname: Nakashima
authors.affiliation: Division of Neuropsychiatry, Department of Neuroscience, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi, Japan; Department of Psychiatry, Yamaguchi Grand Medical Center, Hofu, Yamaguchi, Japan.
authors.forename: Teruyuki
authors.initials: T
authors.lastname: Hobara
authors.affiliation: Division of Neuropsychiatry, Department of Neuroscience, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi, Japan.
authors.forename: Naoko
authors.initials: N
authors.lastname: Higuchi
authors.affiliation: Division of Neuropsychiatry, Department of Neuroscience, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi, Japan.
authors.forename: Fumihiro
authors.initials: F
authors.lastname: Higuchi
authors.affiliation: Division of Neuropsychiatry, Department of Neuroscience, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi, Japan; Katakura Hospital, Ube, Yamaguchi, Japan.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Nakano
authors.affiliation: Division of Neuropsychiatry, Department of Neuroscience, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi, Japan; Konan Hospital, Matsue, Shimane, Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Otsuki
authors.affiliation: Division of Neuropsychiatry, Department of Neuroscience, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi, Japan; Shinwaen Hospital, Onoda, Yamaguchi, Japan.
authors.forename: Tomohiko
authors.initials: T
authors.lastname: Shibata
authors.affiliation: Division of Neuropsychiatry, Department of Neuroscience, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi, Japan.
authors.forename: Toshio
authors.initials: T
authors.lastname: Watanuki
authors.affiliation: Division of Neuropsychiatry, Department of Neuroscience, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi, Japan; Health Administration Center, Yamaguchi University Organization for University Education, Yamaguchi, Yamaguchi, Japan.
authors.forename: Toshio
authors.initials: T
authors.lastname: Matsubara
authors.affiliation: Department of Biomolecular Engineering Applied Molecular Bioscience, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi, Japan.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Fujita
authors.affiliation: Department of Radiology, Tokyo Metropolitan Geriatric Hospital, Tokyo, Japan.
authors.forename: Keigo
authors.initials: K
authors.lastname: Shimoji
authors.affiliation: Division of Neuropsychiatry, Department of Neuroscience, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi, Japan.
authors.forename: Hirotaka
authors.initials: H
authors.lastname: Yamagata
authors.affiliation: Division of Neuropsychiatry, Department of Neuroscience, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi, Japan.
authors.forename: Yoshifumi
authors.initials: Y
authors.lastname: Watanabe
mesh_terms: D000368:Aged; D000679:Amygdala / Q000473:pathology; D016022:Case-Control Studies; D003863:Depression / Q000473:pathology*; D003866:Depressive Disorder / Q000473:pathology; D056324:Diffusion Tensor Imaging; D005260:Female; D066128:Gray Matter / Q000473:pathology*; D006179:Gyrus Cinguli / Q000473:pathology; D006801:Humans; D008297:Male; D017397:Prefrontal Cortex / Q000473:pathology*; D066127:White Matter / Q000473:pathology*
keywords: Diffusion tensor; MRI; Medial frontal; Uncinate fasciculus; Voxel-based morphometry