A study in the Archives of General Psychiatry shows that deep brain stimulation (DBS) is a safe and effective intervention for treatment-resistant depression (TRD) in patients with either unipolar major depressive disorder (MDD) or bipolar ll disorder (BP).
Men and women aged 18 to 70 years with a moderate-to-severe major depressive episode after at least 4 adequate antidepressant treatments. Ten patients with MDD and 7 with BP were enrolled from a total of 323 patients screened.
Intervention Deep brain stimulation electrodes were implanted bilaterally in the subcallosal cingulate white matter. Patients received single-blind sham stimulation for 4 weeks followed by active stimulation for 24 weeks. Patients then entered a single-blind discontinuation phase; this phase was stopped after the first 3 patients because of ethical concerns. Patients were evaluated for up to 2 years after the onset of active stimulation.
There was a significant decrease in depression and increase in function in those subjects with continuing stimulation. Remission and response rates were 18 percent and 41 percent after 24 weeks; 36 percent and 36 percent after one year and 58 percent and 92 percent after two years of active stimulation. Patients who achieved remission did not experience a spontaneous relapse.
The authors concluded that “the findings of this study support the long-term safety and antidepressant efficacy of subcallosal cingulate DBS for (TRD) and suggest equivalent safety and efficacy for TRD in patients with BP.
