Symptom networks of therapy-seeking individuals with comorbid psychosis and PTSD.

Among individuals with a psychotic disorder, the presence of trauma and posttraumatic stress disorder (PTSD) is associated with worse functional impairment, reduced quality of life, symptom persistence, and poorer treatment outcomes (Hassan & De Luca, ; Seow et al., ; Thomas, Höfler, Schäfer, & Trautmann, ). A greater understanding of the relationship between posttraumatic sequelae and psychosis symptoms is warranted, as this may contribute to improved assessment and intervention (Hardy, van de Giessen, & van den Berg, ; Schäfer & Fisher, ). In the context of a biopsychosocial vulnerability to psychosis, trauma may contribute to psychosis symptoms via trauma-related processes implicated in the development of PTSD such as emotion regulation, intrusive trauma memories, and cognitions or schemas (e.g. Berry & Bucci, ; Freeman et al., ; Garety et al., ; Hardy, ; Longden, Madill, & Waterman, ). For example, experiencing trauma may lead to attempts to manage the associated threat through hyperarousal or dissociation (Read, Fosse, Moskowitz, & Perry, ; Schäfer & Fisher, ). During a traumatic event, arousal-induced changes to information processing may result in decontextualized memories later emerging as intrusive trauma memories (Brewin & Patel, ). Poorly integrated intrusive trauma memories may then manifest as hallucinatory experiences, with their content directly or indirectly reflecting traumatic events (Berry & Bucci, ; Longden, Madill, & Waterman, ; McCarthy-Jones & Longden, ; van den Berg et al., ). Trauma memories shape hallucinatory content, and how these experiences are interpreted, potentially giving rise to paranoia. When individuals try to manage these threatening perceptions through avoidance, dissociation, or hypervigilance, they inadvertently reinforce their psychotic symptoms instead of reducing them (Freeman et al., ; Freeman & Garety, ). Emotion regulation and negative beliefs have been shown to mediate the relationship between trauma and psychosis (Hardy et al., ; Peach et al., ; Williams, Bucci, Berry, & Varese, ), while evidence for intrusive trauma memories is inconclusive (Williams, Bucci, Berry, & Varese, ). Further, there has been relatively little research examining the relative contribution of core PTSD symptoms (re-experiencing, hyperarousal, and avoidance) and those reflective of complex PTSD (cPTSD), operationalized as ‘disturbances of self-disorganization’ (DSO) (negative self-concept, relationship difficulties, and affective dysregulation) (International Classification of Diseases 11th edition (ICD-11), World Health Organization (WHO, ). In a preliminary investigation, Panayi et al. () found that both core PTSD and DSO symptoms mediated the relationship between trauma and positive symptoms in people with psychosis diagnoses, with PTSD having twice the effect compared to DSO. In a subsequent study using Ecological Sampling Methodology (ESM) in a sample of people with psychosis and PTSD, both DSO and PTSD were found to predict voices, visions, and paranoia, with the former found to have a larger effect in the flow of daily life, particularly for paranoia (Panayi et al., ). However, neither of these studies examined the relationship of specific DSO symptom clusters with psychosis.