Researchers are working on new approaches to treatment-resistant depression. They offer hope to people who haven't been able to control their depression with traditional methods. Currently, some of these approaches are available for people with depression only through research studies.
Here are some of the newest advances for tackling treatment-resistant depression.
Serotonin acts as a neurotransmitter, a type of chemical that helps relay signals from one area of the brain to another. Although serotonin is manufactured in the brain, where it performs its primary functions, some 90% of our serotonin supply is found in the digestive tract and in blood platelets.
Transcranial Magnetic Stimulation (TMS, or rTMS) sends bursts of energy -- from electromagnets -- to specific areas of the brain. This treatment is thought to affect nerve cell communication in the brain that may play a role in depression.
The procedure is fairly simple and can be done in a doctor's office. It was approved by the FDA as a standard (nonexperimental) treatment for depression in October, 2008. The TMS device itself has two parts: an insulated wire coil (that can look like a paddle) and a box that supplies the power. During the procedure, the doctor or a technician will place the "paddle" against your scalp. The specific area of your scalp depends on what part of the brain your doctor is trying to affect. When switched on, the wire coil creates a magnetic field that can painlessly penetrate your brain. This magnetic field excites the targeted brain areas. Sessions often last about 30 minutes. You might be treated 5 days a week for 4 to 6 weeks.
While more research needs to be done, TMS seems to have few risks and side effects, and it doesn't require hospitalization. Some people feel muscle contractions in the scalp. Rarely, TMS causes headaches or dizziness. But no evidence suggests that it affects the memory, like electroconvulsive therapy (ECT) sometimes can. However, TMS is a different treatment than ECT and has not been shown to have comparable efficacy to ECT. TMS could cause a seizure, but experts say that's very unlikely with a risk of about 1 in a thousand people.
Many studies using TMS with treatment-resistant depression have shown favorable results. For instance, one small study published in 2005 in Biological Psychiatry compared TMS with a sham treatment (or placebo). TMS treatment was more than six times as successful in causing remission of symptoms. Overall, remission from depression has been shown to occur in about 1 in 3 people.
Magnetic Seizure Therapy (MST) is an experimental procedure that uses strong magnetic fields to trigger a controlled seizure in the brain. The effects are similar to those of ECT. For reasons that doctors don't entirely understand, these seizures can relieve the symptoms of depression rapidly. MST requires a stay in the hospital. During the procedure, you would need to be under general anesthesia. Doctors hope that because the stimulation can be more accurately targeted than ECT, it may have less of an effect on memory.
Much more research needs to be done on MST. According to a 2005 article in Primary Psychiatry, only 40 people worldwide have ever received this treatment. However, the limited evidence suggests that it may be a promising treatment option.
Deep Brain Stimulation is an invasive surgical procedure in which electrodes implanted in specific brain areas deliver a targeted electric current to relieve the symptoms of depression. It is already used as a treatment for Parkinson's disease. The electrodes that are surgically implanted in certain regions of the brain are powered by a battery pack implanted in the chest or abdomen. While there has so far been only very limited research on this approach for treatment-resistant depression, the limited results have been promising. One small study published in 2005 in the journal Neuron looked at six people with depression who had not responded to medications, therapy, or ECT. Six months after deep brain stimulation treatment, four still felt positive effects. Three had complete remission of their depression.
While these new treatments are exciting, most are still experimental. Doctors aren't sure yet how well they work long term or what the effects will be. But if you're interested in trying one, talk to your doctor about signing up for a clinical trial.
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