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Brain Volume in 1 st Episode Schizophrenia From the June issue of the British Journal of Psychiatry-I believe these findings are best explained through glucocorticoid (cortisol) neurotoxicity-they are non-specific in schizophrenia and are observed in bipolar disorder and major depressive disorder. Cortisol expression upregulates dopaminergic neurotransmission as well as other processes. Neuroimaging studies have demonstrated reversibility of venrtriculomegaly (dilated ventricles) in good outcome patients-this fits with a neural stress model since we know that atrophic processes, particularly in hippocampal regions, can potentially be reversed once the offending stressor is removed (for humans this can be a combination of external and internal stimuli). REVIEW ARTICLE Brain volume in first-episode schizophrenia Systematic review and meta-analysis of magnetic resonance imaging studies R. GRANT STEEN, PhD, COURTNEY MULL, MD, ROBERT MCCLURE, MD, ROBERT M. Correspondence: Dr R. Grant Steen, Department of Psychiatry, University of North Carolina at Chapel Hill, Campus Box 7160, Chapel Hill, North Carolina 27599-7160, USA. Tel: +1 919 966 8382; e-mail: Grant_Steen@med.unc.edu Declaration of interest: None. Background: Studies of people with schizophrenia assessed using magnetic resonance imaging (MRI) usually include patients with first-episode and chronic disease, yet brain abnormalities may be limited to those with chronic schizophrenia. Aims: To determine whether patients with a first episode of schizophrenia have characteristic brain abnormalities. Method: Systematic review and meta-analysis of 66 papers comparing brain volume in patients with a first psychotic episode with volume in healthy controls. Results: A total of 52 cross-sectional studies included 1424 patients with a first psychotic episode; 16 longitudinal studies included 465 such patients. Meta-analysis suggests that whole brain and hippocampal volume are reduced (both P<0.0001) and that ventricular volume is increased (P<0.0001) in these patients relative to healthy controls. Conclusions: Average volumetric changes are close to the limit of detection by MRI methods. It remains to be determined whether schizophrenia is a neurodegenerative process that begins at about the time of symptom onset, or whether it is better characterised as a neurodevelopmental process that produces abnormal brain volumes at an early age. Copyright © 2006 The Royal College of Psychiatrists. |