title: Increased pituitary volume in schizophrenia spectrum disorders.
abstract: While hypothalamic-pituitary-adrenal (HPA) axis hyperactivity has been implicated in psychotic disorders, previous magnetic resonance imaging (MRI) studies of the pituitary gland volume in schizophrenia have yielded controversial results. It is also unknown whether patients with schizophrenia spectrum such as schizotypal disorder exhibit pituitary volume changes. In this study, we investigated the pituitary volume using MRI in 47 schizotypal disorder patients (29 males, mean age=25.0 years), 72 schizophrenia patients (38 males, mean age=26.2 years), and 81 age and gender matched healthy controls (46 males, mean age=24.5 years). Both patient groups had a larger pituitary volume compared with controls, but no difference was found between the schizophrenia and schizotypal patients. The pituitary volume was larger in females than in males for all diagnostic groups. There was no association between the pituitary volume and type (typical versus atypical), daily dosage, or duration of antipsychotic medication in either patient group. These findings are consistent with a stress-diathesis model of schizophrenia and further suggest that the schizotypal patients share HPA axis hyperactivity with young established schizophrenia patients reflecting a common vulnerability to stress within the schizophrenia spectrum.
authors.affiliation: Melbourne Neuropsychiatry Centre, Department of Psychiatry, University of Melbourne and Melbourne Health, Victoria 3053, Australia. tsutomu@med.u-toyama.ac.jp
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Takahashi
authors.forename: Michio
authors.initials: M
authors.lastname: Suzuki
authors.forename: Dennis
authors.initials: D
authors.lastname: Velakoulis
authors.forename: Valentina
authors.initials: V
authors.lastname: Lorenzetti
authors.forename: Bridget
authors.initials: B
authors.lastname: Soulsby
authors.forename: Shi-Yu
authors.initials: SY
authors.lastname: Zhou
authors.forename: Kazue
authors.initials: K
authors.lastname: Nakamura
authors.forename: Hikaru
authors.initials: H
authors.lastname: Seto
authors.forename: Masayoshi
authors.initials: M
authors.lastname: Kurachi
authors.forename: Christos
authors.initials: C
authors.lastname: Pantelis
mesh_terms: D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D010902:Pituitary Gland / Q000473:pathology*; D012559:Schizophrenia / Q000473:pathology*; D012737:Sex Factors; D018709:Statistics, Nonparametric; D055815:Young Adult