Acute Stress Disorder vs. PTSD: What’s the Difference?

People in Los Angeles whose homes have burned down and firefighters combating the blazes may develop post-traumatic stress disorder (PTSD). But acute stress disorder is another less well-known but officially recognized mental health condition that develops after exposure to a traumatic events.

Acute stress disorder, which is listed in theDiagnostic and Statistical Manual of Mental Disorders, 5th edition, Text Revision (DSM-5-TR), results in symptoms that last three days up to a month.

The key difference between acute stress disorder and PTSD is the duration of the symptoms. A PTSD diagnosis requires that someone have symptoms for at least a month.

The symptoms of acute stress disorder and PTSD overlap. The symptoms of acute stress disorder include intrusive thoughts, negative mood, disassociation, avoidance (efforts to avoid upsetting memories and external reminders of the event) and arousal (disturbed sleep, irritability). The criteria for meeting the DSM-5-TR diagnosis of acute stress disorder include direct or indirect exposure to a traumatic event and development of nine or more symptoms in those five categories.

Characterizations of the evidence about the likelihood of developing PTSD after acute stress disorder vary. A Wolters Kluwer UpToDate article on acute stress order says between 40% and 80% of those with acute stress disorder go on to develop PTSD. The UpToDate article notes that 30% to 60% of those who develop PTSD had met the criteria of having acute stress disorder. That’s a wide range. If the low end is accurate then only a minority of people with PTSD experienced acute stress disorder.

A review and meta-analysis published in the journal Trauma, Violence, & Abuse showed that the rates of acute stress disorder varied with the triggering trauma event, ranging from 14.% for war-related trauma to 36 for interpersonal trauma. The review and meta-analysis encompassed 70 studies published between May 2017 and October 2019.

The UpToDate article was written by Richard Bryant, Ph.D., D.Sc., of the University of New South Wales in Sydney, Australia, a leading expert on acute stress disorder and the author of who has published many articles and research findings about acute stress disorder. In the UpToDate article, Bryant lists different types of traumatic events and the proportion of people who develop acute stress disorder afterward. The range is similar to the one in the Trauma, Violence & Abuse review. Bryant cites one study showing that 13% of people in motor vehicle accidents develop acute stress disorder. Another he cites put the proportion at 19%. At the high end were those witnessed a mass shooting, with 33% developing acute stress disorder.

In an UpToDate article on treatment, Bryant advises waiting two weeks after the trauma exposure before treating acute stress disorder to “allow for transient symptoms to abate and stressors to minimize.” When symptoms are severe(suicidal ideation, severe psychosocial dysfunction) or there might be barriers to providing treatment after two weeks, then treatment should start sooner, he wrote. Bryant discusses cognitive-behavioral therapy as the primary way to treat acute stress disorder and selective serotonin reuptake inhibitors as adjunctive pharmacotherapy.