title: Insular volume abnormalities associated with different transition probabilities to psychosis.
abstract: BACKGROUND
  Although individuals vulnerable to psychosis show brain volumetric abnormalities, structural alterations underlying different probabilities for later transition are unknown. The present study addresses this issue by means of voxel-based morphometry (VBM).
  
  
  METHODS
  We investigated grey matter volume (GMV) abnormalities by comparing four neuroleptic-free groups: individuals with first episode of psychosis (FEP) and with at-risk mental state (ARMS), with either long-term (ARMS-LT) or short-term ARMS (ARMS-ST), compared to the healthy control (HC) group. Using three-dimensional (3D) magnetic resonance imaging (MRI), we examined 16 FEP, 31 ARMS, clinically followed up for on average 3 months (ARMS-ST, n=18) and 4.5 years (ARMS-LT, n=13), and 19 HC.
  
  
  RESULTS
  The ARMS-ST group showed less GMV in the right and left insula compared to the ARMS-LT (Cohen's d 1.67) and FEP groups (Cohen's d 1.81) respectively. These GMV differences were correlated positively with global functioning in the whole ARMS group. Insular alterations were associated with negative symptomatology in the whole ARMS group, and also with hallucinations in the ARMS-ST and ARMS-LT subgroups. We found a significant effect of previous antipsychotic medication use on GMV abnormalities in the FEP group.
  
  
  CONCLUSIONS
  GMV abnormalities in subjects at high clinical risk for psychosis are associated with negative and positive psychotic symptoms, and global functioning. Alterations in the right insula are associated with a higher risk for transition to psychosis, and thus may be related to different transition probabilities.
authors: Department of Psychiatry, University of Basel, Switzerland.
authors: R
authors: R
authors: Smieskova
authors: P
authors: P
authors: Fusar-Poli
authors: J
authors: J
authors: Aston
authors: A
authors: A
authors: Simon
authors: K
authors: K
authors: Bendfeldt
authors: C
authors: C
authors: Lenz
authors: R-D
authors: RD
authors: Stieglitz
authors: P
authors: P
authors: McGuire
authors: A
authors: A
authors: Riecher-Rössler
authors: S J
authors: SJ
authors: Borgwardt
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D014150:Antipsychotic Agents / Q000627:therapeutic use; D001931:Brain Mapping / Q000379:methods; D016022:Case-Control Studies; D002540:Cerebral Cortex / Q000187:drug effects / Q000473:pathology*; D018450:Disease Progression; D004198:Disease Susceptibility; D005260:Female; D005500:Follow-Up Studies; D006212:Hallucinations / Q000473:pathology; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D062706:Prodromal Symptoms; D011569:Psychiatric Status Rating Scales; D011618:Psychotic Disorders / Q000188:drug therapy / Q000473:pathology* / Q000523:psychology; D055815:Young Adult
chemical_list: D014150:Antipsychotic Agents