Unilateral right and bilateral dorsolateral prefrontal cortex transcranial magnetic stimulation in treatment post-traumatic stress disorder: A randomized controlled study

•Bilateral rTMS compared to the sham group showed greater symptom reductions in session five and endpoint.•There were no significant differences between the bilateral and unilateral groups at endpoint.•Unilateral compared to the sham group showed greater symptom reductions at endpoint.•There were no significant differences between the unilateral and sham groups in session five. Repetitive transcranial magnetic stimulation (rTMS) is a potential non-invasive treatment for post-traumatic stress disorder (PTSD). However, the treatment parameters of rTMS required to optimize therapeutic efficacy remains unclear. The aim of the present study was to investigate the efficacy of bilateral rTMS and unilateral right rTMS and compare the efficacy of bilateral rTMS and unilateral rTMS on PTSD symptoms. Sixty-five veterans with current combat-related PTSD symptoms were randomly selected to receive bilateral rTMS (1200 pulses at 20 Hz followed by 1200 pulses per session), unilateral right rTMS (2400 pulses at 20 Hz) or sham rTMS over the dorsolateral prefrontal cortex (DLPFC). Results showed significant differences among the 3 groups. Patients demonstrated significant PTSD symptom reductions in the bilateral group compared to the sham group in session five and endpoint. There were no significant differences between the bilateral and unilateral right groups at endpoint. Unilateral right group when compared to sham group showed greater symptom reductions from baseline to endpoint. There were no significant differences between the unilateral right and sham groups in session five. Our findings suggest that bilateral and unilateral right rTMS are superior to sham rTMS but does not support the hypothesis that bilateral rTMS is more effective than unilateral high-frequency right-sided rTMS.