title: Pituitary volume predicts future transition to psychosis in individuals at ultra-high risk of developing psychosis.
abstract: BACKGROUND
  We examined pituitary volume before the onset of psychosis in subjects who were at ultra-high risk (UHR) for developing psychosis.
  
  
  METHODS
  Pituitary volume was measured on 1.5-mm, coronal, 1.5-T magnetic resonance images in 94 UHR subjects recruited from admissions to the Personal Assessment and Crisis Evaluation Clinic in Melbourne, Australia and in 49 healthy control subjects. The UHR subjects were scanned at baseline and were followed clinically for a minimum of 1 year to detect transition to psychosis.
  
  
  RESULTS
  Within the UHR group, a larger baseline pituitary volume was a significant predictor of future transition to psychosis. The UHR subjects who later went on to develop psychosis (UHR-P, n = 31) had a significantly larger (+12%; p = .001) baseline pituitary volume compared with UHR subjects who did not go on to develop psychosis (UHR-NP, n = 63). The survival analysis conducted by Cox regression showed that the risk of developing psychosis during the follow-up increased by 20% for every 10% increase in baseline pituitary volume (p = .002). Baseline pituitary volume of the UHR-NP subjects was smaller not only compared with UHR-P (as described above) but also compared with control subjects (-6%; p = .032).
  
  
  CONCLUSIONS
  The phase before the onset of psychosis is associated with a larger pituitary volume, suggesting activation of the HPA axis.
authors: Melbourne Neuropsychiatry Centre, Department of Psychiatry, The University of Melbourne, Royal Melbourne Hospital, Melbourne, Australia.
authors: Belinda
authors: B
authors: Garner
authors: Carmine M
authors: CM
authors: Pariante
authors: Stephen J
authors: SJ
authors: Wood
authors: Dennis
authors: D
authors: Velakoulis
authors: Lisa
authors: L
authors: Phillips
authors: Bridget
authors: B
authors: Soulsby
authors: Warrick J
authors: WJ
authors: Brewer
authors: Deidre J
authors: DJ
authors: Smith
authors: Paola
authors: P
authors: Dazzan
authors: Gregor E
authors: GE
authors: Berger
authors: Alison R
authors: AR
authors: Yung
authors: Maarten
authors: M
authors: van den Buuse
authors: Robin
authors: R
authors: Murray
authors: Patrick D
authors: PD
authors: McGorry
authors: Christos
authors: C
authors: Pantelis
mesh_terms: D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D010902:Pituitary Gland / Q000473:pathology*; D011569:Psychiatric Status Rating Scales; D011618:Psychotic Disorders / Q000473:pathology*; D012306:Risk; D012565:Schizophrenic Psychology; D015996:Survival Rate; D013997:Time Factors