In a trial that pitted transcranial, direct-current stimulation (tDCS) against the antidepressant escitalopram (Lexapro), researchers found that lessening of depression was about the same for either treatment.
“We found that antidepressants are better than tDCS and should be the treatment of choice,” said lead researcher Dr. Andre Brunoni. He’s director of the Service of Interdisciplinary Neuromodulation at the University of Sao Paulo.
“In circumstances that antidepressant drugs cannot be used, tDCS can be considered, as it was more effective than placebo,” he said.
The researchers used the Hamilton Depression Rating Scale. This test has a score range of zero to 52, with higher scores indicating more depression.
People who received brain stimulation lowered their depression score by 9 points. Those taking Lexapro had depression scores drop by 11 points. Patients receiving placebo experienced a drop of 6 points in their depression score, the researchers found.
“tDCS has been increasingly used as an off-label treatment by physicians,” Brunoni said. “Our study revealed that it cannot be recommended as a first-line therapy yet and should be investigated further.”
The report was published June 29 in the New England Journal of Medicine.
Dr. Sarah Lisanby is director of the Division of Translational Research at the U.S. National Institute of Mental Health. “When you consider if this treatment adds anything to the ways we have to treat depression, you want to know that a new treatment is better than or at least as good as what’s available today,” she said.
“But this study failed to show that tDCS was better than medication,” said Lisanby, who wrote an accompanying journal editorial.
Lisanby pointed out that unapproved tDCS units are being sold on the internet. She cautioned that trying brain stimulation at home to relieve depression or enhance brain function is risky business, because side effects can include mania.
“There are people who are doing do-it-yourself tDCS,” she said. “People are trying to find ways to treat depression, but it’s important for them to know that tDCS is experimental and not proven to be as effective or more effective than antidepressant medications.”
To get a better idea of how well brain stimulation worked for depression, Brunoni and colleagues randomly assigned 245 patients suffering from depression to one of four groups. One group had brain stimulation plus a placebo pill, another had fake brain stimulation plus Lexapro. The third group had brain stimulation plus Lexapro, and the final group had fake brain stimulation plus a placebo.
Brain stimulation involved wearing sponge-covered electrodes on the head. The treatment was given for 15 consecutive days at 30 minutes each, then once a week for seven weeks.
Lexapro was taken daily for three weeks, after which the daily dose was increased from 10 milligrams (mg) to 20 mg for the next seven weeks.
After 10 weeks, patients receiving brain stimulation fared no better than those taking Lexapro. Patients receiving brain stimulation, however, suffered from more side effects, the researchers found.
Specifically, patients receiving brain stimulation had higher rates of skin redness, ringing in the ears and nervousness than those receiving fake brain stimulation.
In addition, two patients receiving brain stimulation developed new cases of mania. That condition can include elevated mood, inflated self-esteem, decreased need for sleep, racing thoughts, difficulty maintaining attention and excessive involvement in pleasurable activities.
Patients taking Lexapro reported more frequent sleepiness and constipation.
Brunoni, however, is not ready to write off brain stimulation as a treatment for depression based on this study.
“We did not test, in this study, the combined effects of tDCS with other techniques, such as cognitive behavior therapy and other antidepressant drugs,” he said.
“Previous findings from our group showed that tDCS increases the efficacy of antidepressant drugs, however, it should not be used alone, and its use must be supervised by physicians due to the side effects,” Brunoni said.
Lisanby said the tDCS dose in the study may be in question. She said it may have to be adjusted to each individual patient in terms of how strong the electrical stimulation should be. The treatment length also needs to be individualized, as does what part of the brain it should be directed toward.
Also, “we need larger studies to give us the definitive answer about whether tDCS is better than the treatments we have today,” Lisanby said.