Psychotic experiences in people who have been sexually assaulted

Kilcommons, Aoiffe M. and Morrison, Anthony P. and Knight, Alice and Lobban, Fiona (2008) Psychotic experiences in people who have been sexually assaulted. Social Psychiatry and Psychiatric Epidemiology, 43 (8). pp. 602-611. ISSN 0933-7954

Abstract

Objective In recent years, there has been a call for greater awareness of the relationship between trauma and psychosis, and several studies involving patients with psychotic disorders have found a link between traumatic life experience and the development of psychosis. However, little research has examined psychotic experiences in a traumatised population. Method This study investigated psychotic experiences in a sample of 40 survivors of sexual assault (SA) compared to a control group without a history of sexual assault (measured using a self-report questionnaire) and examined the psychological factors that may contribute to the development of psychotic experiences in sexually traumatised individuals. In particular, the role of dissociation and cognitive factors such as post-traumatic cognitions were explored. Results Of the 26 sexually assaulted participants that were interviewed, 46% reported auditory hallucinations and 46% reported visual hallucinations. A significantly higher rate of psychotic phenomena (delusional ideation and predisposition to hallucinations) was found in the sexually assaulted group compared to the control group. Severity of SA trauma was significantly associated with severity of PTSD and psychotic symptomatology. Dissociation was strongly associated with all measures of psychotic phenomena and negative cognitions about the self and the world were associated with predisposition to hallucinations and delusional ideation. Regression analyses revealed that after controlling for the severity of SA trauma, dissociation and negative beliefs about the self significantly predicted delusional distress, and dissociation significantly predicted predisposition to visual hallucinations. Conclusions These exploratory findings support the idea that psychotic phenomena may be caused by traumatic life experiences and highlight the need for further research. The implications of these results for research and clinical practice are discussed.