A Current Approach to Depression
Date: October 15, 2009
A transcranial magnetic stimulation (TMS) system was recently unpacked in Johns Hopkins Hospital’s Meyer 3 suite, where it’s become the centerpiece of a new patient service. Out of the box in ways more than literal, TMS offers an FDA-approved alternative therapy for major depression in adults who’ve given antidepressants a valiant trial and not been helped.
TMS induces weak electric currents that excite targeted sites in the brain. Why that can ease depression is far from clear, says psychiatrist Irving Reti, who directs Hopkins Psychiatry’s new Brain Stimulation Program. But having a noninvasive treatment that doesn’t have whole-body effects is reason enough for making it available, he says.
“The main question,” Reti explains, “is efficacy.” With TMS, relief from depression appears variable. Some patients report that their depression lifts completely; others see little effect. The benefit averages out, according to some 30 trials conducted worldwide, to about a quarter of patients reporting significant relief. Then follow-up antidepressants sustain it.
“There’s a real need to be able to identify who’s most likely to be helped,” Reti says, The fact that TMS takes a time commitment—the recommended protocol is 40 minutes daily, five days a week for four to six weeks—underscores the need.
Safety, however, isn’t in question. “The risk of seizures, which might be a concern, is exceedingly low,” Reti adds. Even more important to patients is the lack of the cognitive side effects that can occur with electroconvulsive therapy. “Aside from mild headache in some,” Reti says, “patients don’t have complaints.”
This could make TMS a good option for people who can’t tolerate antidepressant medications or could be endangered by drug interactions. “We may also find out it’s useful in pregnancy,” Reti adds. The way is open, then, for clinical trials. As a start, the Hopkins group has two under way. One will study TMS in teens age 15 to 18 with entrenched depression. The recent warnings about antidepressants in this group, Reti says, spur that trial on.
A second study—with adults—uses a variation of TMS that penetrates deeper brain. Because the technique’s electromagnet is open to creative design, an experimental version of TMS can reach beyond the 3 centimeters of prefrontal cortex that standard therapy touches. Exciting deeper orbitofrontal cortical pathways that control pleasure and motivation may make TMS more effective, Reti says.
Call 410-955-5212 to refer a patient. For research information: 410-614-1732.
More about Irving Reti: http://www.hopkinsmedicine.org/psychiatry/expert_team/faculty/R/Reti.html