Objective: To investigate clinical response rates of Deep Brain Stimulation (DBS)
as an intervention for treatment resident depression (TRD).
Method: We performed a Pubmed search using the search terms deep brain stimulation,
treatment resistant depression, DBS and TRD which resulted in three-hundred and seventythree
records. Eighty-four articles were screened and duplicates were removed. Inclusion
criteria were: 1.) Diagnosis of Major Depressive Disorder, 2.) Well documented TRD
involving failure of prior established pharmacological treatments, 3.) Controlled trials,
uncontrolled observational studies and case series, 4.) Intervention used was DBS and 5.) Measures of
depressive symptomology pre and post treatment using a validated psychiatric scale to allow assessment of
response. Exclusion criteria include: a reanalysis of pre-published data, review articles, single case reports,
non-English studies and studies involving non-human animal models. Twelve articles were eligible, with 2
being excluded as they were case reports. Consequently, ten articles met criteria and were included in the
Results: Overall, 10 studies were compiled and analyzed for this systematic review, with the number of
participants in the study ranging from 4 to 30. 4 of the 6 studies showed 50% or more improvement in
measures of clinical response in the subcallosal cingulate white matter /brodmann area 25 neuroanatomic
regions. The ventral anterior internal capsule and ventral striatum sites of stimulation showed 71% and 23%
clinical response rates in 2 studies. The nucleus accumbens elicited a 45% clinical response rate. Finally, the
supero-lateral branch of the medial forebrain bundle (bilaterally) resulted in 86% clinical response rate in 1
Conclusion: Given the morbidity and mortality associated with Major Depressive Disorder and the challenges
of TRD, the studies to date strongly support further systematic investigation of the use of DBS in the
treatment of refractory major depressive disorder.
There is promising data to show that DBS is an effective intervention for TRD.
Further investigation is needed to assess DBS as an intervention, particularly with larger sample.
sizes needed in future studies
The samples sizes reviewed in the studies are small.
The inclusion of open label research design.
Limited comparison across studies due to differences in patient selection, electrode placement and
variable duration of treatment.