Sarah Bendall1,2, Natalie Peach Peach3, Simon Cropper4, Pamela Sun5, Mario Alvarez-Jimenez1,2; 1Orygen: The National Centre of Excellence in Youth Mental Health, 2The Centre for Youth Mental Health, University of Melbourne, 3University of New South Wales and National Drug and Alcohol Research Centre, 4School of Psychological Sciences, University of Melbourne, 5School of Psychological Sciences, Monash University
Objective. There is increasing evidence that childhood trauma plays a role in the aetiology of psychosis and in particular hallucinations and delusions. Cognitive models implicate post-traumatic intrusions as a mechanism by which childhood trauma leads to hallucinations. Model of delusions involve both post-traumatic intrusions and trauma-related beliefs as primary mechanisms. This study investigated relationships between childhood trauma, hallucinations and delusions, post-traumatic intrusions and trauma-related beliefs while accounting for comorbid symptoms. Methods. Sixty-six people with first episode psychosis aged between 15 and 24 years were assessed for hallucinations, delusions, childhood trauma, post-traumatic intrusions, post-traumatic avoidance, and trauma-related beliefs. Results. Fifty-three percent of the sample had experienced childhood trauma, and 27% met diagnostic criteria for post-traumatic stress disorder. Multiple regression analyses revealed that post-traumatic intrusions (but not childhood trauma, post-traumatic avoidance, or trauma-related beliefs) were independently associated with hallucination severity (β = .53, p = .01). Post-traumatic intrusions and trauma-related beliefs (but not childhood trauma or post-traumatic avoidance) were independently associated with delusion severity (β = .67, p < .01 and β = .34, p < .01 respectively). Conclusions. These findings support cognitive models that implicate post-traumatic intrusions in hallucination aetiology, and post-traumatic intrusions and trauma-related beliefs in delusion aetiology. This has implications for the treatment of trauma and post-traumatic stress disorder symptoms in people with psychosis. Research trialling interventions that specifically target post-traumatic intrusions and trauma-related beliefs in people with early psychosis who have experienced childhood trauma is recommended.
