Influence of obstetric complication severity on brain morphology in schizophrenia: an MR study

The purpose of this study was to determine if a causal relationship exists between obstetric complications (OCs) severity and linear magnetic resonance (MR) measurements of brain atrophy in patients with schizophrenia. Linear measurements of ventricular enlargement (bifrontal span, Evans ratio, and bicaudate ratio) and hippocampal atrophy (interuncal distance) were completed on MR images obtained in 47 patients with schizophrenia. Regression analysis was used to look at association with OCs severity, assessed by the ''Midwife protocol'' of Parnas and colleagues. The relationship between MR measurements and phenomenologic variables such as age at onset, illness duration, and exposure to antipsychotic medications was explored. The relationship between MR measurements, OCs severity, and symptom presentation was also investigated. OCs severity was significantly associated with MR measurements of ventricular enlargement (bifrontal span, Evans ratio). As the severity of OCs increased, bifrontal span and Evans ratio increased. This effect was independent of age at onset, illness duration, or even antipsychotic treatment. Interestingly, bifrontal span, Evans ratio, and OCs severity score all showed a significant positive correlation with hallucinatory symptomatology. Although confirmatory studies are needed, our findings would support the idea that environmental factors, in this case severe OCs, might partly contribute to ventricular abnormalities in schizophrenia. (orig.)