BACKGROUND: Dissociation is often related to psychologic trauma and is also commonly correlated with posttraumatic stress disorder (PTSD). Schneiderian symptoms occur in dissociative disorder and PTSD, whereas dissociation and trauma are also frequent in patients with schizophrenia. Dissociation and schneiderian symptoms may reflect posttraumatic symptomatology in some patients diagnosed with schizophrenia who might not develop PTSD. METHOD: Seventy-one patients completed an interview assessing symptoms of schizophrenia, depression, dissociative disorder, and PTSD. Data were collected using the Positive and Negative Syndrome Scale, the Montgomery-Asberg Depression Rating Scale, the Arbeitsgemeinschaft Methodik und Dokumentation in der Psychiatrie scale for dissociation, and a Structured Clinical Interview for the Diagnostic and Statistical Manual of Mental Disorders, Revised Third Edition-based questionnaire. Multiple analysis of covariance was used to compare psychopathologic measures between groups with or without PTSD criteria A1 and A2, PTSD, and high and low levels of dissociation, controlling for substance abuse. RESULT: Trauma and dissociation were associated with more severe symptoms of schizophrenia. Especially high dissociation was associated with an increase in symptom load, whereas criterion A and PTSD had little or no such effect. DISCUSSION: In the present study, those with more severe schizophrenic and depressive symptoms were also characterized by high dissociation. The possible relation to trauma and schizophrenic diathesis is discussed along with the limitations of the study.
