TORONTO – The most effective ways to diagnose and treat posttraumatic stress disorder in military populations is at issue after the results of a recent study showed that a third of soldiers who previously would have qualified for the diagnosis do not under updated criteria. The matter is far from settled, however, and continues to be a matter of debate.
Data from a randomized, controlled study published last year (Lancet Psychiatry 2014;1:269-77)* and presented at the annual meeting of the American Psychiatric Association indicate that about a third of soldiers who would have received a clinical diagnosis of PTSD under the DSM-IV criteria do not meet the standard under the DSM-5, released in 2013.
The DSM-5 definition added criteria denoting a person’s efforts to avoid any person, place, or thing that causes them to remember details or feelings experienced during a specific traumatic event. According to former Army psychiatrist Col. (Ret.) Charles W. Hoge, this kind of emotional suppression is exactly what military, law enforcement, and first responder personnel are trained to do in order to accomplish their duties. Indeed, his study indicated that most of the soldiers who did not meet the clinical threshold for PTSD failed criterion C, the section that addresses avoidance.
“The reason to change a definition is to improve clinical utility or improve specificity, but what we’ve done is just shifted the deck chairs,” said Dr. Hoge during his presentation at the meeting.
Not so, said Dr. Matthew J. Friedman, who served on the DSM-5 Work Group that addressed PTSD, and recently retired as executive director of the Veterans Affairs’ National Center for PTSD. In an interview, Dr. Friedman disagreed with framing the findings in terms of clinical utility, particularly if the diagnostic criteria are seen as “easily and reliably utilized by different clinicians.” In that case, Dr. Friedman said in the DSM-5 field trials conducted prior to the manual’s release, the proposed PTSD criteria proved to be among the “best.”
Rather than view the findings merely as a shuffling of seats, Dr. Friedman suggested the findings could lead to a deeper line of inquiry around whether there is in fact a response bias in military personnel who might be less likely to “endorse avoidance symptoms. If the study had been done by a structured interview with a trained clinician instead of by self-report, would the results have looked the same?”
Dr. Matthew J. Friedman
In addition to increasing the number of criteria for PTSD from 17 to 20 symptoms, including the avoidant criteria, the DSM-5 reworded 8 symptoms, and further specified symptom clusters from three groups to four, with the addition of alterations in cognitions and mood to the third cluster, and alterations in arousal and reactivity becoming the fourth. The DSM-5 also reclassified the disorder from one of anxiety to one of trauma and stress.
Dr. Hoge, currently a researcher at the Center for Psychiatry and Neuroscience at Walter Reed Army Institute of Research in Silver Spring, Md., and his colleagues conducted a head-to-head comparison of the number of PTSD diagnoses obtained according to criteria in either the DSM-IV or the DSM-5. They surveyed 1,822 infantry soldiers for a single brigade combat team, more than half of whom had been deployed to Iraq or Afghanistan. Each survey included items from both the DSM-IV’s PTSD Check List, specific for “stressful experiences,” as well as the PCL-5 from the DSM-5. The questions from each were separated in the same survey by several other health-related items. Two versions of the survey were created and distributed randomly across the cohort; one version of the study listed the DSM-IV PCL-S questions first, the other survey had the PCL-5 version first.
The demographic and health outcomes in each group were essentially identical: Respondents were almost entirely male, aged 18-25 years, and roughly half of each group was married. Nearly one-fifth of each group was found by the survey to have moderate to severe general anxiety disorder.
The prevalence rates of PTSD in both survey groups were nearly identical: 12.9% vs. 12.2%, respectively; however, 30% of those surveyed who previously would have met the criteria for PTSD in the DSM-IV did not meet the DSM-5 criteria. Meanwhile, 28% of those who met DSM-5 criteria would not have met the DSM-IV criteria.
Dr. Friedman said the method used in Dr. Hoge’s study did not specifically explore the effect of the A criteria that identify the level of actual exposure to a traumatic event and a person’s immediate reaction to it. The DSM-IV stipulated in criterion A2 that a person experience “fear, helplessness, or horror” directly after a traumatic event. “One of the things that we found is that many soldiers who have all of the PTSD symptoms were ineligible for a PTSD diagnosis because they did not meet the A2 criterion.”