The distribution of psychosis, ICD-11 PTSD and complex PTSD symptoms among a trauma-exposed UK general population sample

Background: Co-occurrence of psychosis and posttraumatic stress disorder (PTSD) symptoms has been demonstrated, but the ICD-11 marks a significant divergence in the formulation of PTSD with a focus on the core symptoms and the addition of complex PTSD (CPTSD).Objective: To evaluate the distribution of psychosis and traumatic stress symptoms using the ICD-11 conceptualisation of PTSD and CPTSD.Method: A latent class analysis was conducted on psychosis symptoms, PTSD and CPTSD among a random adult sample from the UK general population with a history of traumatic events (N = 1,051).Results: Six classes were identified; a low-symptom class, a PTSD-class, a CPTSD-class, a class characterized by disturbances in self-organization alone as well as two classes characterized by CPTSD and various levels of psychosis symptom endorsement. Cumulative childhood adversity predicted membership of the PTSD, CPTSD and comorbid classes in a dose-response manner with the strongest effects observed for classes characterised by comorbid symptoms.Conclusion: The present study confirms the co-occurrence of psychosis symptoms and ICD-11 PTSD and CPTSD. Psychosis symptoms did not emerge in isolation from traumatic stress symptoms, underpinning the need for a greater recognition of psychosis symptoms as part of the broader clinical picture among trauma-exposed populations.