Post-traumatic stress disorder: the role of trauma, pre-existing psychiatric disorders, and gender.

Background: The study is aimed at investigating the influence of trauma type, pre-existing psychiatric disorders with an onset before trauma, and gender on post-traumatic stress disorder (PTSD).

Methods: Traumas, PTSD and psychiatric disorders were assessed in a representative sample of 4075 adults aged 18-64 years using the Composite International Diagnostic Interview. Pre-existing DSM-IV diagnoses of anxiety disorders, depressive disorders, somatoform disorders, alcohol abuse and dependence, nicotine dependence, gender, and the type of trauma were analysed with logistic regressions to estimate the influence of these factors on the risk for developing PTSD.

Results: The lifetime prevalence of exposure to any trauma did not vary by gender. The conditional probability of PTSD after exposure to trauma was higher in women (11.1% SE = 1.58) than men (2.9% SE = 0.83). Univariate analyses showed that pre-existing anxiety disorders, somatoform disorders and depressive disorders significantly increase the risk of PTSD. Multivariate analyses revealed that specific types of trauma, especially rape and sexual abuse, pre-existing anxiety disorders and somatoform disorders are predictors of an increased risk of PTSD, while gender and depressive disorder were not found to be independent risk factors.

Conclusion: Women do not have a higher vulnerability for PTSD in general. However, especially sexually motivated violence and pre-existing anxiety disorders are the main reasons for higher prevalences of PTSD in women.