Efficacy of High-Frequency Repetitive Transcranial Magnetic Stimulation in Treatment-Resistant Depression

Abstract

We examined the efficacy of high-frequency repetitive transcranial magnetic stimulation (rTMS) in 419 patients with treatmentresistant depression. The patients received daily sessions of rTMS over the left prefrontal cortex as an adjuvant to pharmacotherapy. The rTMS intensity was set at 100% of the motor threshold and 25 Hz stimulation, with train duration of 2 seconds delivered at 30-second intervals. A full course comprised 1000 magnetic pulses. Depression was rated using the Hamilton Depression Rating Scale (HAMD) before and after treatment. Response was defined as a 50% reduction in the HAMD score. Patients with HAMD scores of less than 8 were considered to be in remission. The mean HAMD score for the study group decreased from 22.59 + 5.92 to 10.50 + 5.83 (P < .001). After the treatment period, 268 (64%) out of 419 patients demonstrated significant mood improvements, as indexed by a reduction of more than 50% on the HAMD score. In addition, 140 patients (33.4%) attained remission (HAMD score <8); and 11 patients achieved a partial response. Treatment was generally well tolerated, and no serious adverse effects were reported. In conclusion, high-frequency (25 Hz) rTMS was well tolerated and found to be statistically and clinically effective in patients with treatment-resistant depression. This study contributed to the existing evidence of the antidepressant effect of rTMS in the treatment of depression.