More pain, depression, anxiety
Higher levels of self-reported derealization at 2 weeks post trauma predicted higher levels of PTSD, anxiety, and depression as well as more bodily pain and impairment in work, family, and social life at 3 months.
“When we accounted for baseline levels of posttraumatic stress symptoms and trauma history, higher levels of self-reported derealization still predicted higher posttraumatic stress disorder and depression symptoms at 3 months,” said Dr. Lebois.
Additional adjusted analyses showed increased vmPFC activity during the fearful face task predicted 3-month self-reported PTSD symptoms.
Dr. Lebois “highly recommends” clinicians screen for dissociative symptoms, including derealization, in patients with trauma. Self-report screening tools are freely available online.
She noted patients with significant dissociative symptoms often do better with a “phase-oriented” approach to trauma treatment.
“In phase one, they learn emotional regulation skills to help them take more control over when they dissociate. Then they can successfully move on to trauma processing in phase two, which can involve exposure to trauma details.”
Although the field is not yet ready to use brain scans to diagnose dissociative symptoms, the new results “take us one step closer to being able to use objective neuroimaging biomarkers of derealization to augment subjective self-report measures,” said Dr. Lebois.
A limitation of the study was it could not determine a causal relationship, as some derealization may have been present before the traumatic event. The findings may not generalize to other types of dissociation, and the derealization assessment was measured only through a self-report 2 weeks after the trauma.
Another limitation was exclusion of patients with self-inflicted injuries or who were involved in domestic violence. The researchers noted the prevalence of derealization might have been even higher if such individuals were included.
An important investigation
In an accompanying editorial, Lisa M. Shin, PhD, department of psychology, Tufts University, and department of psychiatry, Massachusetts General Hospital and Harvard Medical School, Boston, notes having both clinical and neuroimaging variables as well as a large sample size makes the study “an important investigation” into predictors of psychiatric symptoms post-trauma.
Investigating a specific subtype of dissociation – persistent derealization – adds to the “novelty” of the study, she said.
Dr. Lisa M. Shin
The new findings “are certainly exciting for their potential clinical relevance and contributions to neurocircuitry models of PTSD,” she writes.
Some may argue administering a short, self-report measure of derealization “is far more efficient, cost-effective, and inclusive than conducting a specialized and expensive fMRI scan that is unlikely to be available to everyone,” notes Dr. Shin.
However, she added, a potential benefit of such a scan is identification of specific brain regions as potential targets for intervention. “For example, the results of this and other studies suggest that the vmPFC is a reasonable target for transcranial magnetic stimulation or its variants.”
The new results need to be replicated in a large, independent sample, said Dr. Shin. She added it would be helpful to know if other types of dissociation, and activation in other subregions of the vmPFC, also predict psychiatric outcomes after a trauma.
The study was supported by National Institute of Mental Health grants, the U.S. Army Medical Research and Material Command, One Mind, and the Mayday Fund. Dr. Lebois has received grant support from NIMH, and her spouse receives payments from Vanderbilt University for technology licensed to Acadia Pharmaceuticals. Dr. Shin receives textbook-related royalties from Pearson.
A version of this article first appeared on Medscape.com.