Although previous open-label studies have supported the use of deep brain stimulation for treatment-resistant depression, the first large-scale, randomized, sham-controlled trial has failed to find that deep brain stimulation leads to significantly better response rates than placebo.
“While initial open-label trials of deep brain stimulation at the ventral capsule/ventral striatum target were promising, the results of this first controlled trial were negative," said researcher Darin Dougherty, MD director of neurotherapeutics at Massachusetts General Hospital and associate professor at Harvard Medical School, Boston.
Dr. Dougherty and colleagues published their findings, which involved 30 patients randomized to 16 weeks of treatment with active deep brain stimulation or sham placebo stimulation at five medical centers across the United States, in Biological Psychiatry.
Researchers found no significant difference in response rates between the active and control groups at the end of treatment. Response was defined as a 50% or more improvement on the Montgomery-Asberg Depression Rating Scale.
Experts advised caution, however, in interpreting the results.
"On first sight, this might be seen as a crisis for the whole field of neurostimulation therapies for depression,” wrote Thomas Schlaepfer, MD, Johns Hopkins University, Baltimore, and University Hospital Bonn, Germany, in a companion piece to the article. “[But we] believe that these are examples of failed studies and not failed treatments."
"It is critical to understand that this study is not a universal indictment of deep brain stimulation as a strategy for depression. It may turn out that stimulating other brain regions or stimulating these regions in different ways could provide important benefit," added John Krystal, MD, the journal’s editor.
Noting the dramatic improvement researchers have seen after patients with treatment-resistant depression receive deep brain stimulation, Dr. Dougherty agreed with the comments and said the research team will consider alternative study designs for future clinical trials.
1. Dougherty DD, Rezai AR, Carpenter LL, et al. A randomized sham-controlled trial of deep brain stimulation of the ventral capsule/ventral striatum for chronic treatment-resistant depression. Biological Psychiatry. 2015;78:240-248.