The Nithsdale Schizophrenia Surveys. XII. 'Neurodevelopmental' Schizophrenia: a search for clinical correlates and putative aetiological factors.

Abstract

The aim was to examine in a population of schizophrenic patients the clinical correlates of 'neurodevelopmental' schizophrenia and their relationship to putative aetiological factors. Premorbid social adjustment, premorbid schizoid and schizotypal personality traits, and the obstetric history of 40 schizophrenic patients and their 102 sibs were assessed through interviews with their mothers. Patients' premorbid level of intelligence was assessed by the National Adult Reading Test and current symptoms by the Positive and Negative Syndrome Scale and the Subjective Deficit Syndrome Scale. Patients had more schizoid and schizotypal traits than their sibs. They showed a deterioration in social adjustment between childhood and adolescence; sibs' social adjustment improved. There were statistically significant associations between current negative schizophrenic symptoms, premorbid deterioration in social adjustment, and schizoid and schizotypal personality traits, and between an early age of onset of illness and the same premorbid assessments. There was no evidence that patients with a family history of severe mental illness leading to hospitalisation, or a history of definite obstetric complications, had poorer premorbid functioning or more severe current symptoms. We have confirmed clinical correlates of 'neurodevelopmental' schizophrenia but found no association between these and obstetric complications or a family history of severe mental disorder.