NeuroNotes: What is the Actual Risk of Deep Brain Stimulation for Depression?

NeuroNotes is a new section of the ASSFN NeuroPulse newsletter designed to share research and clinical observations with the stereotactic and functional neurosurgery community. Our inaugural article shares the therapeutic potential for deep brain stimulation (DBS) for Treatment-Resistant Depression.

Therapeutic potential of DBS for Treatment-Resistant Depression (TRD)

The therapeutic potential of DBS for treatment-resistant depression has been studied for more than two decades. Although the procedure has been shown to be relatively safe, when discussing the procedure with patients enrolled in clinical trials, clinicians cite adverse event rates based on other DBS indications. To formally address the incidence of adverse events in TRD patients treated with DBS, we performed a scoping review of the literature (Lapa et al., Neurosurgery. 2024 Sep 1;95(3):509-516). From the 28 studies pooled for analysis, adverse event data were extracted from 353 patients who had electrodes implanted in various targets.

Categorizing Adverse Events from the Literature

Adverse events were categorized as psychiatric in nature, hardware-related, and stimulation-related. The most common psychiatric adverse events were worsening of depression symptoms (15-30%) and anxiety (about 10%). These were observed primarily in patients who did not respond to treatment, during clinical fluctuations, and when batteries were inadvertently depleted. Mania/hypomania occurred in approximately 15% of patients treated with DBS in the anterior limb of the internal capsule, with a much lower incidence (0.5%) in patients receiving stimulation in the subgenual cingulum.

The incidence of hardware-related side effects was similar to other DBS applications, with a possible lower rate of hemorrhages (0.8%) in patients with depression. The only notable stimulation-related neurologic adverse event was oscillopsia in patients receiving medial forebrain bundle stimulation. The rates of suicide or attempted suicide were 2.5% and 7.6%, respectively. This was found to be comparable or even lower than the figures reported in cohorts of TRD patients published in the literature.

Safety Profile for DBS for TRD

Overall, our review provides average data on the safety profile of DBS for TRD and may help clinicians estimate the complication rate when discussing clinical trial data.

References:
Lapa JDS, Duarte JFS, Campos ACP, Davidson B, Nestor SM, Rabin JS, Giacobbe P, Lipsman N, Hamani C. Adverse Effects of Deep Brain Stimulation for Treatment-Resistant Depression: A Scoping Review. Neurosurgery. 2024 Sep 1;95(3):509-516. doi: 10.1227/neu.0000000000002910.

By Clement Hamani

Sunnybrook Research Institute

University of Toronto