Acute stress disorder, or ASD, was introduced into the DSM-IV. In the 2013 DSM-5, ASD was reclassified as a trauma- and stressor-related disorder 1. A diagnosis of ASD has played a critical role in facilitating access to health care after exposure to a trauma. Debate continues regarding ASD as a predictor of posttraumatic stress. Although many of the symptoms of these disorders overlap, they differ in terms of symptoms as well as the onset and duration of symptoms. 1. Acute stress disorder and post-traumatic stress disorder, or PTSD, can both develop following exposure to a traumatic event. Each causes significant functional difficulties in one or more areas of your life.