Epidemiologic studies of trauma, posttraumatic stress disorder, and other psychiatric disorders.

This paper reviews recent epidemiologic studies of posttraumatic stress disorder (PTSD) in the general population. Estimates of the prevalence of exposure to traumatic events vary with the method used to ascertain trauma exposure and the definition of the stressor criterion. Changes in the DSM-IV definition of "stressor" have increased the number of traumatic events experienced in the community that can be used to diagnose PTSD and thus, the number of PTSD cases. Risk factors for PTSD in adults vary across studies. The 3 factors identified as having relatively uniform effects are 1) preexisting psychiatric disorders, 2) a family history of disorders, and 3) childhood trauma. In civilian populations, women are at a higher risk for PTSD than are men, following exposure to traumatic events. Most community residents have experienced 1 or more PTSD-level traumas in their lifetime, but only a few succumb to PTSD. Trauma victims who do not succumb to PTSD are not at an elevated risk for the subsequent onset of major depression or substance use disorders, compared with unexposed persons.