For people who have been exposed to violence or trauma, and who naturally experience some symptoms of anxiety, what approaches are most useful for PTSD prediction? The majority of people exposed to violence or trauma do not go on to develop posttraumatic stress disorder or PTSD, but, depending on the nature of the trauma (sexual trauma has the highest risk) a significant minority will go on to develop PTSD and these individuals may benefit from more intensive early intervention.
European researchers looked at the question of PTSD prediction two different ways. Their study looked at data from 171 assault survivors, who completed a self-report assessment of acute symptoms at 2 weeks after the traumatic event and a structured clinical interview to assess PTSD diagnosis at 6 months after the traumatic event.
First they looked at all of the symptoms in the DSM-IV PTSD diagnostic criteria and rated them individually in terms of the “Odds Ratio” of developing chronic PTSD if the individual symptom was present at two weeks. Using this criteria the greatest risk of developing PTSD was in those who experienced recurrent and intrusive dreams or nightmares (those who had this symptom at two weeks had a more than three times higher risk of developing chronic PTSD, compared with those who did not) and those who experienced recurrent or distressing intrusive memories (again with a more than three times increased risk).
Others have looked at PTSD prediction in this way, finding various combinations of symptoms that provide the best PTSD prediction.
These researchers also looked at how individual symptoms affected each other. They conducted a path analysis designed to show which symptoms seemed most central to the development of chronic PTSD and which symptoms seemed to exert their effect indirectly through their relationship to other symptoms. Using this technique they showed that three symptoms appear to be most closely connected to the development of PTSD: intrusive dreams and nightmares, easy startle, and a sense of a foreshortened future.
Of these three, a sense of a foreshortened future might be the symptom that is the hardest to explain or describe. One of my patients so I’ve been seeing for a few weeks and who was in a terrible and sudden automobile accident, describes it this way: “I feel as if I am certain to die in the next year. I constantly feel as if I will be in another accident or something else will happen that will end my life.”
Feelings of detachment and emotional numbing related to a sense of a foreshortened future. Avoiding situations that reminded the person of the trauma as well as sleep disruption and intrusive memories all related to the experience of intrusive dreams and nightmares, but it was intrusive nightmares that seemed to best predict chronic PTSD. Hypervigilance and easy startle were very strongly correlated with each other and easy startle somewhat predicted the development of chronic PTSD.
The implication of this study is that it might be possible to focus on a reduced symptom list of the key mediators of developing chronic PTSD: intrusive nightmares, a sense of a foreshortened future, and to a lesser extent, easy startle. Of these three, intrusive nightmares and easy startle have been shown to respond to medications such as prazosin and clonidine that reduce sympathetic nervous system activity. And a sense of a foreshortened future should be very responsive to targeted psychotherapy interventions.
The next step for this group of researchers is to see if developing a specific treatment approach that focuses on these core symptoms results in preventing the development of chronic PTSD for those exposed to acute trauma.
Haag C, Robinaugh DJ, Ehlers A, Kleim B. Understanding the Emergence of Chronic Posttraumatic Stress Disorder Through Acute Stress Symptom Networks. JAMA Psychiatry. Published online May 10, 2017. doi:10.1001/jamapsychiatry.2017.0788
Bryant RA, Creamer M, O’Donnell M, et al. Acute and chronic posttraumatic stress symptoms in the emergence of posttraumatic stress disorder. JAMA Psychiatry. 2017;74(2):135-142.
Kleim B, Ehlers A, Glucksman E. Early predictors of chronic post-traumatic stress disorder in assault survivors. Psychol Med. 2007;37(10):1457-1467.