Pituitary volume and early treatment response in drug-naïve first-episode psychosis patients

• Published in: Schizophrenia research 2009-08, Vol.113 (1), p.65-71
• Main Authors: Garner, B, Berger, G.E, Nicolo, J.P, Mackinnon, A, Wood, S.J, Pariante, C.M, Dazzan, P, Proffitt, T.M, Markulev, C, Kerr, M, McConchie, M, Phillips, L.J, Pantelis, C, McGorry, P.D
• Format: Article
• Language: English
• Subjects: Adolescent; Antipsychotic Agents - therapeutic use; Biological and medical sciences; Dibenzothiazepines - therapeutic use; Dose-Response Relationship, Drug; Female; First-episode psychosis; Humans; Imaging, Three-Dimensional - methods; Logistic Models; Magnetic resonance imaging; Magnetic Resonance Imaging - methods; Male; Medical sciences; Models, Statistical; Neuropharmacology; Pharmacology. Drug treatments; Pituitary gland; Pituitary Gland - drug effects; Pituitary Gland - pathology; Psychiatric Status Rating Scales; Psychiatry; Psycholeptics: tranquillizer, neuroleptic; Psychology. Psychoanalysis. Psychiatry; Psychopharmacology; Psychotic Disorders - drug therapy; Psychotic Disorders - pathology; Quetiapine Fumarate; Severity of Illness Index; Time Factors; Treatment response; Young Adult
• ISSN: 0920-9964; 1573-2509
• DOI: 10.1016/j.schres.2009.05.008

Abstract Background An early response to antipsychotic treatment in patients with psychosis has been associated with a better course and outcome. However, factors that predict treatment response are not well understood. The onset of schizophrenia and related disorders has been associated with increased levels of stress and hyper-activation of the hypothalamic-pituitary-adrenal (HPA) axis. This study examined whether pituitary volume at the onset of psychosis may be a potential predictor of early treatment response in first-episode psychosis (FEP) patients. Methods We investigated the relationship between baseline pituitary volume and symptomatic treatment response over 12 weeks using mixed model analysis in a sample of 42 drug-naïve or early treated FEP patients who participated in a controlled dose-finding study of quetiapine fumarate. Logistic regression was used to examine predictors of treatment response. Pituitary volume was measured from magnetic resonance imaging scans that were obtained upon entry into the trial. Results Larger pituitary volume was associated with less improvement in overall psychotic symptoms (Brief Psychiatric Rating Scale (BPRS) P = 0.031) and positive symptoms (BPRS positive symptom subscale P = 0.010). Regardless of gender, patients with a pituitary volume at the 25th percentile (413 mm3 ) were approximately three times more likely to respond to treatment by week 12 than those at the 75th percentile (635 mm3 ) (odds ratio = 3.07, CI: 0.90–10.48). Conclusion The association of baseline pituitary volumes with early treatment response highlights the importance of the HPA axis in emerging psychosis. Potential implications for treatment strategies in early psychosis are discussed.