Magnet Therapy May Help Treat Depression When Drugs Don't Work

If antidepressant medications aren’t working for long-term, also known as major, depression, some people may find relief from a new therapy that uses magnetic pulses to stimulate the brain. The new study comes from researchers at the Medical University of South Carolina.

Repetitive transcranial magnetic stimulation (rTMS) stimulates the nerve cells in the left prefrontal cortex. The activity of these cells is believed to be reduced in depressed people.

Participants in the current study had suffered from depression for anywhere between 3 months and five years and hadn’t found antidepressants to be effective in relieving it. Mark George and his colleagues used a treatment called repetitive transcranial magnetic stimulation (rTMS) to stimulate the nerve cells in the left prefrontal cortex. The activity of these cells is believed to be reduced in depressed people.

The team performed rTMS, which consisted of 3000 magnetic pulses over a period of 37.5 minutes, to half the participants. The other half of the group, serving as controls, got a “sham” treatment, which was similar to the experimental treatment except that a metal insert blocked the magnetic pulse from entering the brain. Patients were restricted from taking antidepressants during the experimental period, and for several weeks before it began.

George and his team found that after three weeks of treatment, 14% of the treated group reported relief from their depression, vs. only 5% of the control group, which the authors say is a significant difference. When the researchers administered the therapy to control participants and to patients who had not been helped by the first treatment, 30% of all of these patients felt that they were free of depression. The main side-effects, found in both the experimental and sham treatment groups, were headache and discomfort at the site of stimulation.

The authors sum up their findings by saying that “high-intensity rTMS for at least 3 weeks was significantly more likely than sham rTMS to induce remission in antidepressant medication–free patients with moderately treatment-resistant [depression].” They add that that follow-up studies will aim to determine how long the therapy should be administered to be most effective, as well as the long-term benefits of rTMS.

The study was published in the May 2010 issue of Archives of General Psychiatry.