title: Grey matter atrophy in mild cognitive impairment / early Alzheimer disease associated with delusions: a voxel-based morphometry study.
abstract: OBJECTIVE
  Grey matter atrophy in the right hemisphere has been shown to be more severe in dementia patients with delusions, suggesting a neuroanatomical localization that may be pertinent to impending neurodegeneration. Delusional symptoms may arise when atrophy in these areas reduces the regulatory functions of the right hemisphere, in tandem with asymmetric neuropathology in the left hemisphere. We hypothesized that delusional patients with either amnestic mild cognitive impairment (MCI) or early Alzheimer Disease (AD) would experience more pronounced grey matter atrophy in the right frontal lobe compared with matched patients without delusions.
  
  
  METHODS
  We used neuroimaging and clinical data obtained from the Alzheimer's Disease Neuroimaging Initiative. A comparison group of twenty-nine nondelusional MCI/early AD participants were compared with twenty-nine delusional participants using voxel-based morphometry, matched at baseline by age, sex, education, and Mini-Mental State Exam score. All included participants were diagnosed with amnestic MCI at study baseline.
  
  
  RESULTS
  Fifteen voxel clusters of decreased grey matter in participants with delusions were detected. Prominent grey matter decrease was observed in the right precentral gyrus, right inferior frontal gyrus, right insula, and left middle occipital gyrus, areas that may be involved in control of thought and emotions.
  
  
  CONCLUSIONS
  Greater right fronto-temporal grey matter atrophy was observed in MCI or early AD participants with delusions compared to matched patients without delusions. Consistent with our predictions, asymmetric grey matter atrophy in the right hemisphere may contribute to development of delusions through loss of executive inhibition.
authors: Windsor Kwan-Chun
authors: WK
authors: Ting
authors: Corinne E
authors: CE
authors: Fischer
authors: Colleen P
authors: CP
authors: Millikin
authors: Zahinoor
authors: Z
authors: Ismail
authors: Tiffany W
authors: TW
authors: Chow
authors: Keenan Research Centre for Biomedical Science, the Li Ka Shing Knowledge Institute, St. Michael's Hospital, 209 Victoria Street, Toronto, ON, Canada, M5B 1T8. schweizert@smh.ca.
authors: Tom A
authors: TA
authors: Schweizer
mesh_terms: D000368:Aged; D000544:Alzheimer Disease / Q000473:pathology* / Q000503:physiopathology / Q000523:psychology; D001284:Atrophy; D060825:Cognitive Dysfunction / Q000473:pathology* / Q000503:physiopathology / Q000523:psychology; D003430:Cross-Sectional Studies; D003702:Delusions / Q000473:pathology* / Q000503:physiopathology; D005260:Female; D005500:Follow-Up Studies; D005625:Frontal Lobe / Q000473:pathology*; D066128:Gray Matter / Q000473:pathology*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D009483:Neuropsychological Tests; D011569:Psychiatric Status Rating Scales; D013702:Temporal Lobe / Q000473:pathology*