Therapeutic efficacy of bilateral prefrontal slow repetitive transcranial magnetic stimulation in depressed patients with Parkinson's disease: an open study.

Recent studies have suggested that both high- and low-frequency repetitive transcranial magnetic stimulation (rTMS) have antidepressant effects in patients with major depression. We conducted an open study to assess the effects of slow rTMS on mood changes in patients with depression associated with Parkinson's disease (PD). Ten depressed patients with PD (four with major depression and six with dysthymia) received daily sessions of rTMS (frequency, 0.5 Hz; pulse duration, 0.1 msec; field intensity, 10% above the motor threshold) over both prefrontal regions (a total of 100 stimuli per prefrontal region daily) over 10 consecutive days. This treatment resulted in a moderate but significant decrease in scores of the Hamilton Depression Rating Scale (33-37%) and the Beck Depression Inventory (24-34%), which persisted 20 days after finishing the stimulation. In parallel, we observed mild improvement (18-20%) of motor symptoms. No significant adverse effects were reported. These preliminary results suggest the therapeutic potential of daily prefrontal low-frequency rTMS (0.5 Hz) in depression associated with PD.