New data are being published about deep brain stimulation and treatment resistant depression. Especially longer follow up is of importance. In recent published research about deep brain stimulation for treatment resistant depression, six months after surgery, 60% of patients were responders and 35% met criteria for remission, benefits that were largely maintained at 12 months. Moreover, there was no significant loss of effect requiring dose adjustments over time. So once a good stimulus dose, high change that it will remain that way over a long period of time.
With DBS for TRD symptoms typically return rapidly if the device is turned off, if a lead breaks, or if the battery dies. From other areas of neuroscience it is learned that intermittent stimulation of brain areas could provoke longer-term neuroplastic brain changes in these circuits (LTD or LTP), thus moving brain circuits into a more resilient and healthy mode, making symptom recurrence less likely if stimulation is stopped or withdrawn. Exciting trials with intermittent DBS are underway testing these new hypotheses and probably after some time it is probable that the devices can be switched of for good or until recurrence.
In this study twenty patients with TRD underwent serial assessments before and after Subcallosal Cingulate Gyrus DBS. They determined the percentage of patients who achieved a response (50% or greater reduction in the 17-item Hamilton Rating Scale for Depression or remission (scores of 7 or less) after surgery. They also examined changes in brain metabolism associated with DBS, using positron emission tomography.
Results from PET scans. The results indicate that SCG DBS produces striking changes in cognitive and limbic brain areas and they provide a biological basis for the observed improvements in depression in these patients. There is a direct activation of the white matter at target that can lead to either metabolic activation or inhibition in distinct remote brain areas. Antidepressant medications, cognitive behavioral therapy, and electroconvulsive therapy produce similar changes in many of these same brain regions.
- Wound Infection and Hardware removal 3 patients
- Reinsertion of DBS Hardware 1 patient
- Wound Infection Managed with Antibiotics Alone 1 patient
- Perioperative Seizure 1 patient
- Worsening Mood/Irritability 2 patients
- Perioperative Headache 4 patients
- Pain at Pulse Generator Site 1 patient
- No Adverse Effects 7 patients
Limitation of this study is the open label assessment of outcomes
DBS is tried with many more indications. Parkinson’s disease and Obsessive compulsive disorder are the most well known. The Food and Drug Administration has approved deep brain stimulation as a therapy for Obsessive compulsive disorder. In case reports DBS is also tried with addiction, Alzheimers disease, Tourette’s syndrom and even coma. This are all case reports, not evidence based. For a recent overview and intervied about DBS for different indications please read at the Chigaco Tribune, with thanks to @dsaarinen for reminding me on the use of DBS for Alzheimer’s disease.
For a short but very informative video:Deep Brain stimulation for Parkinson’s disease
A LOZANO, H MAYBERG, P GIACOBBE, C HAMANI, R CRADDOCK, S KENNEDY (2008). Subcallosal Cingulate Gyrus Deep Brain Stimulation for Treatment-Resistant Depression Biological Psychiatry, 64 (6), 461-467 DOI: 10.1016/j.biopsych.2008.05.034