March 12, 2004 — High-frequency repetitive transcranial magnetic stimulation (rTMS) may have a therapeutic effect in patients with posttraumatic stress disorder (PTSD), according to the results of a double-blind, placebo-controlled study published in the March issue of the American Journal of Psychiatry.
Hagit Cohen, PhD, and colleagues, from Ben-Gurion University of the Negev in Israel, studied 24 patients (17 men and 7 women) who fulfilled Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, diagnostic criteria for PTSD. Patients were randomly assigned to receive rTMS at low frequency (n = 8) or high frequency (n = 10) or sham rTMS (n = 6).
None of the patients suffered from a chronic medical disease. However, all but four of the subjects were receiving polypharmacy. Patients did not stop or change drug treatment in the three weeks before or during the study. They also continued to receive supportive psychotherapy.
Investigators administered stimulus over the right dorsolateral prefrontal cortex for 20 minutes per day over 10 week days. The placebo group received treatment in the same way as the group receiving high-frequency rTMS, but the coil was held at 90 degrees vertical over the stimulated head area. Patients in the low-frequency rTMS received 1 Hz for 5 seconds per train; the intertrain interval was 55 seconds. Subjects in the high-frequency rTMS group received 10 Hz for 2 seconds per train; the intertrain interval was 58 seconds.
A blinded investigator assessed symptoms of PTSD, anxiety, and depression at baseline, day 5, day 10, and day 24 (14 days after intervention). The investigator used the PTSD Checklist, the Treatment Outcome PTSD Scale, the Hamilton Anxiety Rating Scale, the Hamilton Rating Scale for depression, and the Clinician-Administered PTSD Scale.
During high-frequency rTMS treatment, mean PTSD Checklist scores decreased. Active 10-Hz rTMS was significantly different from the sham ( P < .01) and 1-Hz ( P < .002) treatments in post-hoc Sheffé tests. Mean Treatment Outcome PTSD Scale scores in the high-frequency group decreased by 39.0% from baseline to the end of treatment. Post-hoc Sheffé tests showed a significant effect of rTMS treatment; active 10-Hz rTMS was significantly different from the sham ( P < .05) and 1- Hz ( P < .02) treatments.
The patients who received 10-Hz rTMS showed significant improvement over subjects from the sham ( P < .04) and 1-Hz ( P < .01) groups in the Hamilton anxiety scale scores. Post-hoc tests revealed no significant difference between treatments or times for the Hamilton depression scale, however.
Fourteen patients across all treatment groups reported headache, but treatment was generally well tolerated. Eleven participants across all treatment groups also reported sleep improvement.
"The effect of 10-Hz rTMS was significant and stable for at least 14 days after the last treatment. It is suggested that in further studies the stimulation could be repeated as maintenance therapy, as in [electroconvulsive therapy] procedures," Dr. Cohen and colleagues write. "However, given the small number of patients, our study must be considered preliminary."
Am J Psychiatry. 2004;161:515-524
Reviewed by Gary D. Vogin, MD
Medscape Medical News © 2004
Cite this: Mindy Hung. High-Frequency TMS May Benefit Patients With PTSD - Medscape - Mar 12, 2004.