May 4, 2010 -- A controversial new treatment for depression, rTMS, helps some patients, a rigorous
government-funded study finds.
The treatment is called repetitive transcranial magnetic stimulation. It's
basically an electromagnet. When applied to the skull just behind the left
forehead, the device induces a tiny electric current in a part of the brain
linked to depression.
Because the device carries little risk, the FDA in October 2008
cleared the device for treatment of major clinical depression in adults who
got no relief from first-line antidepressant treatment. But questions remained about
whether the device really helps depression.
The biggest hurdle to studying the device was finding an inactive placebo to
compare it with. In earlier studies, patients and researchers had no trouble
telling the real device from a sham. That's important because the placebo
effect -- the tendency of some people to get better from fake treatment -- is
strong in clinical trials of depression treatments.
After much struggle, the researchers used earphones and electrodes to mimic
the actual sound, sight, and feel of a real rTMS session, says study researcher
Sarah Lisanby, MD, chief of the brain stimulation and therapeutic modulation
division at Columbia University and the New York State Psychiatric
Lisanby and colleagues signed up 190 people who had failed to get relief
from at least one antidepressant medication; many had tried several different
treatments. They received either rTMS or the sham treatment for three
The result: 14% of those treated with rTMS had remission of their
depression, compared with only 5% of those getting the sham treatment.
Those whose depression did not get better after three weeks entered a
continuation trial in which the sham treatment was discontinued and everyone
got rTMS. Thirty percent of the patients in this continuation study had
remission of their depression.
"The effect sizes we report with rTMS are about on par with what you see
with antidepressant medications," Lisanby tells WebMD. "The difference is that
to get into our study, people had to have failed to have responded to a
medication. And studies show that with previous failure to respond to an
antidepressant, the rate of success for a second antidepressant is lower."