Lateral ventricle differences between first-episode schizophrenia and first-episode psychotic bipolar disorder: A population-based morphometric MRI study

Abstract

Objectives. The extent to which psychotic disorders fall into distinct diagnostic categories or can be regarded as lying on a single continuum is controversial. We compared lateral ventricle volumes between a large sample of patients with first-episode schizophrenia or bipolar disorder and a healthy control group from the same neighbourhood. Methods. Population-based MRI study with 88 first-episode psychosis (FEP) patients, grouped into those with schizophrenia/schizophreniform disorder (N=62), bipolar disorder (N=26) and 94 controls. Results. Right and left lateral ventricular and right temporal horn volumes were larger in FEP subjects than controls. Within the FEP sample, post-hoc tests revealed larger left lateral ventricles and larger right and left temporal horns in schizophrenia subjects relative to controls, while there was no difference between patients with bipolar disorder and controls. None of the findings was attributable to effects of antipsychotics. Conclusions. This large-sample population-based MRI study showed that neuroanatomical abnormalities in subjects with schizophrenia relative to controls from the same neighbourhood are evident at the first episode of illness, but are not detectable in bipolar disorder patients. These data are consistent with a model of psychosis in which early brain insults of neurodevelopmental origin are more relevant to schizophrenia than to bipolar disorder.

Key words::

• Psychosis
• schizophrenia
• bipolar affective disorder
• MRI
• lateral ventricles

Acknowledgments

We thank the Brazilian First-Contact Psychosis clinical team for the recruitment of the participants in the community. The authors also thank Claudia C. Leite, Edson Amaro Jr. and Claudio C. Castro for their help in the collection of MRI data. This study was funded by the Wellcome Trust, UK, and FAPESP, Brazil. Paulo R. Menezes, Marcia Scazufca and Geraldo F. Busatto are partly funded by CNPq, Brazil. Maristela Schaufelberger Spanghero is funded by CAPES, Brazil. Pedro G.P. Rosa receives a scholarship from FAPESP, Brazil. Furthermore, this study was presented as a Free Communication in the 9th World Congress of Biological Psychiatry, June 2009, Paris.

Statement of Interest

The authors report no conflict of interest.