1. Home>
2. Specialties>
3. Psychiatry>
4. Summary and Comment

An Evidence-Based Approach to Preventing PTSD

Prolonged exposure seems to help patients at risk.

Acute stress disorder (ASD) after a life-threatening trauma increases the risk for post-traumatic stress disorder. Investigators in Australia randomized 90 patients who had experienced a nonsexual assault or a motor vehicle accident in the previous month and who met DSM-IV criteria for ASD to manual-based prolonged exposure, cognitive restructuring, or wait list. Assessments occurred at 6 weeks and 6 months; the wait-list group was not assessed at 6 months because it received active treatment after 6 weeks.

Therapies comprised five weekly sessions. Exposure included psychoeducation, imaginal exposure in the office and during homework, in vivo exposure to a hierarchy of stimuli, and rehearsal of relapse-prevention strategies. Cognitive restructuring involved standard cognitive-therapy techniques, including psychoeducation, monitoring and modifying automatic thoughts, addressing catastrophic thinking, and counteracting negative appraisals of one’s ability to cope with stress.

In an analysis of completers (77% of enrollees) at 6 weeks, significantly fewer exposure recipients than cognitive-restructuring recipients or wait-list participants met criteria for PTSD (12% vs. 52% and 71%). Among those assessed at 6 months (70% of the 2 active-treatment groups), cognitive-restructuring recipients were 5.7 times more likely than exposure patients to meet PTSD criteria (number needed to treat, 2.96). Exposure was associated with fewer symptoms and better functioning at follow-up than cognitive restructuring.

Comment: Soon after traumatic experiences, re-exposure to the trauma in the office and then in vivo appeared to desensitize patients to distress caused by remembering the event. Avoidance levels also decreased, probably because of patients’ sense of mastery over the trauma. By contrast, single sessions of critical incident stress debriefing (group discussion of the trauma without exposure; used by the U.S. military) and reliving trauma years later do not improve symptoms and may even worsen them (Br J Psychiatry 2006; 189:150). Although cognitive therapy was not harmful, it was less helpful than exposure. Prolonged exposure might also prevent PTSD in patients with ASD after other sorts of traumas.

— Steven Dubovsky, MD

Published in Journal Watch Psychiatry August 11, 2008

Citation(s):

Bryant RA et al. Treatment of acute stress disorder: A randomized controlled trial. Arch Gen Psychiatry 2008 Jun; 65:659.

• Original article (Subscription may be required)
• Medline abstract (Free)