Dissociation as a Causal Pathway from Sexual Abuse to Positive Symptoms in the Spectrum of Psychotic Disorders

Abstract

Background: Although numerous studies have supported the role of childhood maltreatment in the etiology of psychosis, underlying mechanisms have not been well understood yet. The present study aimed to investigate the mediating role of particular forms of dissociation in the relationship between five major types of childhood abuse and psychotic symptoms among patients with schizophrenia spectrum and other psychotic disorders.Methods: In this cross-sectional correlation study, a total of 210 participants, including 140 patients with schizophrenia spectrum and other psychotic disorders (70 first-episode psychotic patients and 70 chronic psychotic patients) and 70 community controls, were selected by systematic random sampling (with the sampling interval of 3) and one-to-one matching, respectively, from among inpatients and outpatients referring to Baharan Psychiatric hospital, Zahedan, Iran, and people living in this region. In this study, the evaluation criteria included Dissociative Experiences Scale, Childhood Trauma Questionnaire-Short Form, and Positive and Negative Syndrome Scale.Results: The obtained results revealed that the mean scores of sexual abuse, emotional abuse, and physical abuse were higher in psychotic patients than community controls (without any significant difference among first-episode psychotic patients and chronic psychotic patients). Furthermore, the highest mean scores of dissociative experiences belonged to chronic psychotic patients. Regarding the three study groups, there was no significant gender-based difference between mean scores of dissociative experiences and various types of childhood maltreatment. Multiple-mediation also indicated that absorption and dissociative amnesia played a mediating role in the relationship between sexual abuse and positive symptoms. Moreover, this study implied the role of physical abuse in predicting psychotic symptoms even in the absence of sexual abuse. Conclusions: This study illustrated specific associations among childhood maltreatment, dissociative experiences, and psychotic symptoms in the clinical population. Thus, to provide appropriate interventions, patients with schizophrenia spectrum and other psychotic disorders needed to be asked about a wide range of possible adverse childhood experiences and dissociative experiences. Nevertheless, further studies using prospective or longitudinal designs need to be carried out to realize the differential contribution of various forms of childhood maltreatment and their potential interactions, more precisely.