title: Apathy correlates with prefrontal amyloid β deposition in Alzheimer's disease.
abstract: OBJECTIVE
  Neuropsychiatric symptoms affect many patients with Alzheimer's disease (AD). ((11)C)Pittsburgh Compound-B (PIB) positron emission tomography (PET) has enabled the in vivo visualisation of brain amyloid-β (Aβ) deposition. This study exploratively investigated the correlation between brain Aβ deposition measured by ((11)C)PIB PET and neuropsychiatric symptoms in AD.
  
  
  METHODS
  Participants were 28 patients (15 women, 13 men) with PIB-positive AD. Clinical assessments included Mini-Mental State Examination, Clinical Dementia Rating scale, neuropsychiatry inventory (NPI) and frontal assessment battery. All patients underwent three-dimensional T1-weighted MRI and ((11)C)PIB PET. The distribution volume ratio (DVR), an index of ((11)C)PIB retention and, thus, Aβ deposition, was estimated voxel by voxel from ((11)C)PIB PET data with partial volume correction. Voxel-based correlation analysis was performed to assess the relationships between DVR and each NPI subscale. Additionally, voxel-based analysis of covariance (ANCOVA) of the DVR images was performed between Patients with AD with and without each neuropsychiatric symptom. Voxel-based morphometry analysis of MRI was also performed.
  
  
  RESULTS
  Apathy subscale was correlated with ((11)C)PIB retention in the bilateral frontal and right anterior cingulate. ((11)C)PIB retention was greater in the bilateral frontal cortex of patients with AD with apathy than those of without apathy. Overlapping areas between the two analyses were the bilateral orbitofrontal gyrus and left superior frontal gyrus. Other NPI subscales were not correlated with ((11)C)PIB retention. Voxel-based morphometry analysis of MRI showed no significant cluster of correlation between grey matter volume and NPI subscales.
  
  
  CONCLUSIONS
  This study revealed that prefrontal Aβ deposition correlates with apathy.
authors.affiliation: Molecular Imaging Center, National Institute of Radiological Sciences, , Chiba, Japan.
authors.forename: Takaaki
authors.initials: T
authors.lastname: Mori
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Shimada
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Shinotoh
authors.forename: Shigeki
authors.initials: S
authors.lastname: Hirano
authors.forename: Yoko
authors.initials: Y
authors.lastname: Eguchi
authors.forename: Makiko
authors.initials: M
authors.lastname: Yamada
authors.forename: Ryuji
authors.initials: R
authors.lastname: Fukuhara
authors.forename: Satoshi
authors.initials: S
authors.lastname: Tanimukai
authors.forename: Ming-Rong
authors.initials: MR
authors.lastname: Zhang
authors.forename: Satoshi
authors.initials: S
authors.lastname: Kuwabara
authors.forename: Shu-Ichi
authors.initials: S
authors.lastname: Ueno
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Suhara
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000523:psychology*; D016229:Amyloid beta-Peptides / Q000378:metabolism*; D057565:Apathy; D005260:Female; D059907:Functional Neuroimaging; D006801:Humans; D008297:Male; D008875:Middle Aged; D017397:Prefrontal Cortex / Q000000981:diagnostic imaging / Q000378:metabolism*; D011569:Psychiatric Status Rating Scales; D011877:Radionuclide Imaging
chemical_list: D016229:Amyloid beta-Peptides
keywords: ALZHEIMER'S DISEASE; AMYLOID; FRONTAL LOBE; NEUROPSYCHIATRY; PET