HUNTINGTON BEACH, CALIF. – Three things have been found to be strong predictors of whether a patient will develop post-traumatic stress disorder following physical trauma, Medical College of Wisconsin, Milwaukee, researchers reported.
Patients are more likely to develop PTSD if they were victims of violence; if they perceive they were grievously injured, regardless of their injury severity score; and if they think they were almost killed, whether that’s true or not.
The researchers used surveys to determine what factors predict PTSD in trauma patients, fourth-year medical student Jessica Anderson said when she presented the findings at the Academic Surgical Conference, which was sponsored by the Association for Academic Surgery and the Society of University Surgeons.
Within about 72 hours of admission, 403 trauma patients completed the 17-question Post-Traumatic Stress Disorder checklist (pdf) and the Short Form-36 – a quality of life survey that assesses mental and physical function; 129 filled out the forms when requested to do so 6 months later.
A previous study found severe PTSD symptoms in 22.5% of patients admitted to the trauma service; in the new study, 18.6% of the 6-month respondents had checklist scores above 44, indicating PTSD.
Victims of violence – shootings, stabbings, or assaults – had mean 6-month checklist scores of 45.79; mean score for accident victims was 32.27 (P = .005).
Higher PTSD scores correlated with lower quality-of-life scores. Assault victims also scored lower on mental functioning at 6 months (P = .001).
"The variables that were statistically significant in predicting PTSD severity at 6 months included assaultive type of mechanism, scene heart rate, perceived injury severity score, and perceived life threat," Ms. Anderson said.
Age and gender were not predictive. On multiple regression analysis, scene heart rate was no longer significant.
Such studies of PTSD in trauma patients are relatively new, said Dr. Karen Brasel, a surgery professor at the college and a trauma surgeon at its associated Froedtert Memorial Lutheran Hospital, also in Milwaukee.
These three factors have been identified before among military personnel and domestic violence victims, but they appear to apply to other trauma victims, as well, she said.
"People don’t really think about PTSD in relation to garden-variety car crashes or getting stabbed in a gang fight," said Dr. Brasel, who is helping to lead efforts at the hospital to address PTSD in trauma patients.
Although nothing can be done about the injury mechanism, the other two contributing factors – the perceptions about injury severity and death risk – may be amenable to cognitive-behavioral therapy (CBT).
Patients admitted to the hospital’s level 1 trauma center are screened as soon as possible for PTSD symptoms with the civilian version of the PTSD Checklist.
Those who score above 44, indicating severe PTSD symptoms, are referred to psychologist Terri deRoon Cassini, Ph.D., who begins to work with them to mitigate PTSD symptoms, and continues to do so after they are discharged.
Since joining the trauma team in September 2008, Dr. deRoon Cassini has used CBT to halt possible PTSD for several hundred assault victims and survivors of car crashes and other accidents. The CBT approach involves disengaging the memory of the event from the autonomic response to it, as it’s the hyperactivated fight-or-flight response that creates and maintains the panic attacks, nightmares, flashbacks, and other PTSD symptoms that make return to a normal quality of life difficult.
Patients tell Dr. deRoon Cassini their stories over and over again; with each retelling, the autonomic response fades. Eventually, the trauma becomes just another memory, not something the body relives 24 hours a day.
"A lot of times people will say, ‘I’m having flashbacks, I’m having nightmares, I’m going crazy. I keep seeing the car flipping over and over and over again. I keep hearing the gun go off,’ " she said.
After the conditioned response is broken through CBT, she helps patients "process what happened and restructure their cognitive perceptions," she said. Eventually they realize "that was really scary, but it’s over," said Dr. deRoon Cassini.
A randomized trial is planned to measure the success of that approach, Dr. Brasel said. In the planned trial, half of newly admitted high scorers on the PTSD checklist will be randomized to CBT, half to no treatment.
They’ll be followed to assess rates of PTSD development, a diagnosis that requires symptoms be present at least 1 month, with the goal of finding out if early intervention helps.
The trial will include salivary cortisol measurements and possibly functional MRI, Dr. Brasel said.
Dr. Brasel, Dr. deRoon Cassini, and Ms. Anderson said they have no conflicts of interest.