Background. While several personality characteristics are implicated in the etiology and phenotypic expression of schizophrenia, little is known about their trait status or clinical correlates during the early course of this disorder.
Method. The stability of five personality characteristics derived from the MMPI-168 was examined in recent-onset schizophrenia patients (n=59) during a psychotic period at study entry and at two out-patient assessments over the following 15 months and in non-patient controls (n=39) at similar time intervals. Among patients, associations between personality characteristics and clinical symptoms and exposure to stressful life events during the study period were also examined.
Results. Multilevel modeling analyses indicated that the between-subjects or trait-like variance components for these characteristics among patients were substantial, albeit smaller than those found for controls. Patients reported higher mean levels of Neuroticism, Cynicism, and Psychotic Ideation and lower mean levels of Psychopathic Tendencies and Denial of Somatic Complaints than controls. Among patients, several personality characteristics were systematically related to mean clinical symptom levels as well as frequency of exposure to dependent, but not independent, life events.
Conclusions. Stable individual differences in personality are detectable during the early course of schizophrenia and may help account for heterogeneity in clinical symptoms and functional outcome.