Transcranial Direct-Current Stimulation Promising in Bipolar Depression
By Anne Harding
NEW YORK—Transcranial direct current stimulation (tDCS) is safe, effective and well-tolerated in patients with bipolar depression, according to results from a small randomized controlled trial.
“This preliminary study showed evidence of efficacy and safety of tDCS as an add-on treatment for bipolar depression,” lead author Dr. Andre Russowsky Brunoni, of the Service of Interdisciplinary Neuromodulation at the University of Sao Paolo in Brazil, told Reuters Health by email.
Existing treatments for bipolar depression have only modest efficacy, and are associated with adverse effects, Dr. Brunoni and his team note in their December 27 online report in JAMA Psychiatry. While repetitive transcranial magnetic stimulation (TMS) has been shown to be effective in both unipolar and bipolar depression, they add, it is costly and has been linked with seizures.
TDCS, less costly and more portable than TMS, involves passing weak direct currents into the brain via electrodes placed on the scalp, usually over the dorsolateral prefrontal cortex. This noninvasive brain stimulation has been found to be effective in unipolar depression, they add, but has not been tested in a sham-controlled trial in patients with bipolar depression.
In the Bipolar Depression Electrical Treatment Trial (BETTER), the researchers randomized 59 patients with bipolar disorder in a major depressive episode to receive tDCS or sham stimulation. Participants completed 10 daily sessions on weekdays only, followed by one session every two weeks until week six. Fifty-two patients completed the trial.
Intention-to-treat analysis showed significantly superior improvement in the active tDCS group than in controls, with a number needed to treat (NNT) of 5.8. The cumulative response rate was 67.6% in the active treatment group, versus 30.4% in the control group (NNT, 2.69). Remission rates were 37.4% with active treatment versus 19.1% for controls, but that difference was not statistically significant. The only adverse events associated with treatment were localized skin redness.
“We have recently published in The New England Journal of Medicine a large non-inferiority trial investigating tDCS efficacy in unipolar depression, and we recently finished a trial testing tDCS efficacy for schizophrenia,” Dr. Brunoni said. “We are also conducting a trial for tDCS in obsessive-compulsive disorder. Our next steps will be to understand better the mechanisms of action of tDCS, using it combined with neuroimaging techniques (spectroscopy and resting state MRI).”
The Brain & Behavior Research Foundation helped to support the study.
JAMA Psychiatry 2017.
(c) Copyright Thomson Reuters 2018. Click For Restrictions - http://about.reuters.com/fulllegal.asp