Prevalence of Posttraumatic Stress Disorder in Schizophrenia Spectrum Disorders: A Systematic Review

Background Posttraumatic stress disorder (PTSD) is a comorbidity often ignored and unexplored in patients with schizophrenia, despite a possible impact on its symptomology. Links and interactions between these disorders are still unknown. This article proposes a systematic review of the prevalence of PTSD in schizophrenia spectrum disorders (SSD). Methods and findings Thirty-eight studies were included. Results Results were heterogeneous with range of prevalence of PTSD varying between 0% and 55%. These wide ranges of prevalence were explained by the utilization of different assessment tools of trauma exposure, not all validated and heterogeneous population of SSD (schizoaffective disorders, comorbid addiction disorders mainly). Nevertheless, 78,9% of the studies found a prevalence of PTSD superior to 10 %. Conclusion Our review suggests a high rate of prevalence of PTSD in schizophrenia, which may be underestimated due to symptoms overlap. Moreover, the absence of difference in trauma exposure between SSD and the general population evokes an increased liability to trauma in patients with SSD.