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, 70 first-episode psychotic patients and 70 chronic psychotic patients were selected by systematic random sampling (with the sampling interval of 3) from among inpatients and outpatients referring to Baharan Psychiatric hospital, Zahedan, Iran, and were matched based on age, gender, and education level. Moreover, 70 age-, gender-, and education level-matched community controls were recruited from hospital staff and their relatives and friends. All of the participants completed a research interview and questionnaires. Data on experiences of childhood maltreatment, psychosis, dissociation, and demographics were collected and analyzed by SPSS V25 software.

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 between first-episode psychotic patients and chronic psychotic patients). Furthermore, the highest mean scores of dissociative experiences belonged to chronic psychotic patients. 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 demonstrated 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 were 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.

Keywords: Dissociation; Psychotic disorders; Sexual abuse.

Fig. 1

Comparing mean scores of Childhood Trauma Questionnaire-Short Form and Dissociative Experiences Scale among three study groups (N = 210). Note. D1: Amnesia; D2: Depersonalization/Derealization; D3: Absorption; EA: Emotional Abuse; EN: Emotional Neglect; PA: Physical Abuse; PN: Physical Neglect; SA: Sexual Abuse. Note. Statistical analyzing applied analysis of variance (ANOVA). SA: F (2, 207) = 26.47^***; Scheffé post hoc test: 1 & 2 > 3. EA: F (2, 207) = 7.06^**; Scheffé post hoc test: 1 & 2 > 3. PA: F (2, 207) = 30.71^***; Scheffé post hoc test: 1 & 2 > 3. EN: F (2, 207) = 1.66. PN: F (2, 207) = 0.13. D1: F (2, 207) = 33.94^***; Scheffé post hoc test: 2 > 1 > 3. D2: F (2, 207) = 28.49^***; Scheffé post hoc test: 2 > 1 > 3. D3: F (2, 207) = 21.59^***; Scheffé post hoc test: 2 > 1 > 3. ^*p < 0.05; ^**p < 0.01; ^***p < 0.001. Note. This clustered bar chart was created by IBM SPSS Statistics V25.0 (www.ibm.com)

Fig. 2

Illustration of the results of the mediation analysis described in the text, which tested dissociative amnesia, depersonalization/derealization, and absorption as the potential mediators of the relationship between sexual abuse and positive symptoms by controlling for physical abuse among patients with schizophrenia spectrum and other psychotic disorders (n = 140). Note. D1: Amnesia; D2: Depersonalization/Derealization; D3: Absorption; PANSS1: Positive Symptoms; SA: Sexual Abuse. P_M: Effect size (ratio of indirect to total effect). ^*p < 0.05; ^**p < 0.01; ^***p < 0.001