Intermittent theta-burst stimulation (iTBS) is a promising therapy for posttraumatic stress disorder (PTSD), according to the results of a study published in the American Journal of Psychiatry.
Noah S. Philip, MD, from the Center for Neurorestoration and Neurotechnology, Providence Veterans Administration Medical Center, and the Department of Psychiatry and Human Behavior, Alpert Medical School of Brown University, Providence, Rhode Island, and colleagues conducted a modified parallel-group, double-blind, sham-controlled trial in 50 veterans with PTSD. After random assignment, half the participants received daily sessions of sham iTBS and the other half received active iTBS over the course of 10 business days. Members of both groups were invited to receive another 10 sessions of unblended active iTBS to determine the effects of additional sessions on outcomes.
Guided by prior studies, iTBS was delivered to the dorsolateral prefrontal cortex. Primary outcomes included retention rate, changes in PTSD symptoms, quality of life, social and occupational function, and depression evaluated at the end of 2 weeks of initial treatment. Secondary outcomes included those measures evaluated 1 month after therapy.
The investigators found significant improvement in social and occupational function and indications of improvement in depression and self-reported PTSD at 2 weeks among those treated with active iTBS. At 1 month, active iTBS proved superior for all outcome measures. Treatment was well tolerated. One quarter of recipients of active iTBS reported treatment site discomfort, whereas none in the sham treatment group did so. However, reports of headache were similar in both groups.
The investigators noted that the majority of clinical benefit occurred in the first week of active treatment, which was surprising, as previous studies of transcranial magnetic stimulation and iTBS had indicated increased therapeutic effect on depression over time. Further, the researchers observed a greater effect on symptoms of depression early in the course of treatment, whereas symptoms of PTSD improved with increased exposure. This indicates a need for increased research into the optimal dose of stimulation, according to the investigators.
Study limitations included the small sample size and the homogeneity of the study population.
“iTBS appears to be a promising new treatment for PTSD. Most clinical improvements from stimulation occurred early, which suggests a need for further investigation of optimal iTBS time course and duration,” the investigators concluded.
Disclosure: One of the study authors declared affiliations with the pharmaceutical industry. Please see the original reference for a full list of authors’ disclosures.
Philip NS, Barredo J, Aiken E, et al. Theta-burst transcranial magnetic stimulation for posttraumatic stress disorder [published online June 24, 2019]. Am J Psychiatry. doi:10.1176/appi.ajp.2019.18101160