[Untreated PTSD in schizophrenia - unrecognized risk factor for recovery and course of illness?].

More recently research has focused on post-traumatic stress disorder (PTSD) as comorbide condition of schizophrenia. Current literature focussing the relationship between PTSD and schizophrenia is reviewed. Evidence is found in support of psychosis as a precondition for development of PTSD, PTSD as vulnerability factor for psychosis as well as psychosis and PTSD both as part of a spectrum of responses to a traumatic event. PTSD may be regarded as risk factor for worse outcome in schizophrenia: Internal stress of reexperiencing the trauma may enhance vulnerability to relapse of illness and proneness to anxiety avoiding coping style with psychosis by adoption of a "sealing over" style, lowering service utilization and compliance. Risk for development of alcohol misuse, cannabis misuse or benzodiazepine misuse and depression may be higher, also worsening the course of schizophrenia. Methodological shortcomings of current studies, ongoing debates on extending DSM-IV criterion A1 definition to psychotic or treatment experiences and implications for clinical assessment and cognitive-behavioural treatment of PTSD in schizophrenia are discussed.