A new pilot study suggests administration of a medication along with traditional behavioral therapy may help individuals with severe post-traumatic stress disorder.
Post-traumatic stress disorder (PTSD) is among the most common, distressing, and disabling medical consequences of combat or other extremely stressful life events.
Traditional therapy for PTSD is exposure therapy, a type of behavioral therapy where patients confront their fears in a safe environment. While this therapy is usually effective, many patients drop out of treatment while others experience symptoms after treatment.
In the new study, researchers used an intervention that had been tested on animal models and has been used for other anxiety disorders.
Investigators examined whether the impact of psychotherapy could be enhanced by administering D-cycloserine (DCS), a drug that does not directly treat the symptoms of PTSD, but rather promotes neuroplasticity, i.e., makes brain circuits better able to remodel themselves in the context of experience.
In the study design, individuals with PTSD were recruited to receive up to 10 weekly sessions of exposure therapy. They were randomized to receive doses of either DCS or placebo before each session, but did not know which they were receiving. The severity of their symptoms was assessed before and after treatment.
Study participants all experienced a reduction in symptoms due to the exposure therapy, regardless of whether they had received DCS augmentation or placebo.
However, DCS enhanced the effects of exposure therapy in a specific subgroup of patients. This group was characterized by individuals with more severe PTSD prior to treatment. As expected, this subgroup needed longer treatment although DCS treatment was associated with a greater reduction in symptoms, as compared to those who received placebo.
“Our study showed that some PTSD patients respond well and fast to exposure and for them, there seems no need to augment the therapy. In contrast, those patients with severe PTSD symptoms and who fail to respond to exposure sessions may benefit from augmentation with DCS,” said first author Rianne de Kleine, Ph.D., a researcher at the Center for Anxiety Disorders in the Netherlands.
“It seems that DCS is beneficial for exactly those patients we aimed for: the more severe patients who do not respond to first-line treatment.”
“This approach may have important implications for the treatment of PTSD,”said Dr. John Krystal, Editor of Biological Psychiatry. “Two decades of brain research suggests that severe psychological stress causes atrophy of some of the fine connections in the brain and reductions in the volume of brain regions involved in emotion and memory. Thus, individuals with PTSD may have deficits in neuroplasticity that get in the way of effective treatment.
“D-cycloserine may reduce this deficit in neuroplasticity and increase the response to psychotherapy, in this case a psychotherapy approach that involves exposing people to reminders and memories of the trauma.”
Researchers say that while the approach seems promising, additional work is necessary to explore whether the combination of behavioral therapy and DCS can become an effective intervention to treat the symptoms of PTSD.