title: Regional thinning of the cerebral cortex in schizophrenia: effects of diagnosis, age and antipsychotic medication.
abstract: Morphological abnormalities of the cerebral cortex have been reported in a number of MRI-studies in schizophrenia. Uncertainty remains regarding cause, mechanism and progression of the alterations. It has been suggested that antipsychotic medication reduces total gray matter volumes, but results are inconsistent. In the present study differences in regional cortical thickness between 96 patients with a DSM-IV diagnosis of schizophrenia (n=81) or schizoaffective disorder (n=15) and 107 healthy subjects (mean age 42 years, range 17-57 years) were investigated using MRI and computer image analysis. Cortical thickness was estimated as the shortest distance between the gray/white matter border and the pial surface at numerous points across the entire cortical mantle. The influence of age and antipsychotic medication on variation in global and regional cortical thickness was explored. Thinner cortex among patients than controls was found in prefrontal and temporal regions of both hemispheres, while parietal and occipital regions were relatively spared. Some hemispheric specificity was noted, as regions of the prefrontal cortex were more affected in the right hemisphere, and regions of the temporal cortex in the left hemisphere. No significant interaction effect of age and diagnostic group on variation in cortical thickness was demonstrated. Among patients, dose or type of antipsychotic medication did not affect variation in cortical thickness. The results from this hitherto largest study on the topic show that prefrontal and temporal cortical thinning in patients with schizophrenia compared to controls is as pronounced in older as in younger subjects. The lack of significant influence from antipsychotic medication supports that regional cortical thinning is an inherent feature of the neurobiological disease process in schizophrenia.
authors.affiliation: Department of Psychiatric Research, Diakonhjemmet Hospital, and Institute of Psychiatry, University of Oslo, Norway. ragnar.nesvag@medisin.uio.no
authors.forename: Ragnar
authors.initials: R
authors.lastname: Nesvåg
authors.forename: Glenn
authors.initials: G
authors.lastname: Lawyer
authors.forename: Katarina
authors.initials: K
authors.lastname: Varnäs
authors.forename: Anders M
authors.initials: AM
authors.lastname: Fjell
authors.forename: Kristine B
authors.initials: KB
authors.lastname: Walhovd
authors.forename: Arnoldo
authors.initials: A
authors.lastname: Frigessi
authors.forename: Erik G
authors.initials: EG
authors.lastname: Jönsson
authors.forename: Ingrid
authors.initials: I
authors.lastname: Agartz
mesh_terms: D000328:Adult; D000367:Age Factors; D017668:Age of Onset; D014150:Antipsychotic Agents / Q000009:adverse effects / Q000627:therapeutic use; D001284:Atrophy; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000187:drug effects / Q000473:pathology*; D039721:Diagnostic and Statistical Manual of Mental Disorders; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000706:statistics & numerical data; D008297:Male; D008875:Middle Aged; D011569:Psychiatric Status Rating Scales / Q000706:statistics & numerical data; D012559:Schizophrenia / Q000175:diagnosis / Q000188:drug therapy / Q000473:pathology*; D013548:Sweden; D014888:Wechsler Scales
chemical_list: D014150:Antipsychotic Agents