In a recent study published in the Journal of Neurology, Neurosurgery and Psychiatryresearchers investigated the effectiveness of deep brain stimulation (DBS) against treatment-resistant obsessive-compulsive disorder (OCD).
OCD is characterized by intrusive and persistent obsessive thoughts and dysfunctional and ritualized behaviors. The disease usually manifests during a critical developmental stage, such as puberty, early adulthood, or childhood. Ablative lesion techniques such as anterior cingulotomy and anterior capsulotomy are well-known surgical approaches to treat symptoms of treatment-resistant OCD (TROCD). Further knowledge of treatment efficacy through studies with various methodological methods is needed for the developing field of DBS for TROCD.
Review: Effectiveness of deep brain stimulation for treatment-resistant obsessive-compulsive disorder: systematic review and meta-analysis. Image Credit: Ralwell/Shutterstock
About the study
In the present study, researchers evaluated the effectiveness of DBS in reducing OCD and co-occurring depressive symptoms in patients with TROCD using a systematic review and meta-analysis.
The standards for systematic reviews and meta-analyses (PRISMA) were followed to produce a systematic review. Studies were reviewed if they met the following requirements: (1) subjects were adults over the age of 18 with a primary diagnosis of OCD according to the criteria of the International Classification of Diseases or the Diagnostic and Statistical Manual of Mental Disorders , fourth or fifth edition (DSM-IV or DSM-V), (2) used the Yale-Brown Obsessive Compulsive Scale (Y-BOCS) to measure outcome (3) DBS was the primary intervention, ( 4) primary outcome was improvement in OCD symptoms after DBS treatment, (5) treatment response defined as a 35% or greater reduction in Y-BOCS score, and (6) published in peer-reviewed journals reading in English.
Using the statistical calculation package R, a meta-analysis was performed. Primary outcomes included mean Y-BOCS difference at most recent follow-up from baseline, treatment effect or percentage decrease in Y-BOCS at most recent follow-up, and responder rate at the most recent follow-up. Two secondary objectives were depression scale response rate and standardized mean difference (SMD) of depression scale scores.
A total of 3,023 records, covering the years 1986 to 2021, were found using the search strategy. Thirty-four studies from 2005 to 2021 were chosen for systematic review and meta-analysis, including nine randomized controlled trials (RCTs). All 352 people were adults with severe to extreme OCD at the start of the study. The studies included three trials of first-line drug therapy, one trial of additional medications, and at least 20 hours of expert exposure and response prevention (ERP) with no persistent response to treatment. Additionally, patients in 67% of studies had to have non-remitting disease for five years or more before being considered for surgery. Of the remaining 11 studies, only one required more than ten years of disease duration and two or more years of non-remitting disease; another required one year of non-remitting disease, while five did not specify.
The team noted that the disease lasted an average of 24.3 years. According to 23 studies, major depressive disorder affects approximately 55% of patients, anxiety disorders affect 10% of people, and personality disorders affect 9.5% of people. RCTs had a median of 10 participants, compared to seven in non-RCTs. The two most frequently discussed stimulation targets were the ventral capsule/ventral striatum (VC/VS) and nucleus accumbens (NAc), followed by the anterior limb internal capsule (ALIC), nucleus du bed, stria terminalis (BNST) and ALIC. /BNST.
The Hamilton Depression Scale was used in 14 surveys. To assess depression before and after surgery, seven studies used the Beck Depression Inventory (BDI), five studies used the Montgomery-Åsberg Depression Rating Scale (MADRS), and one study used the Depression, Anxiety, and Stress Scale (DASS-D). A Hamilton Anxiety Scale was used in 11 of the 16 studies that provided anxiety ratings, the STAI-X1/2 in four of 16, and the DASS-A in 1.46 of 16. Seven of ten seven studies that provided GAF ratings did so exclusively with baseline data.
Approximately 70% of studies provided complete information on serious adverse events (SAEs), including but not limited to hardware problems, infections, seizures, suicide attempts, intracranial hemorrhage (ICH) and the emergence of de novo stimulation-related obsessions. Overall, 31% of patients reported having had at least one SAE. There were 8% or fewer problems with the device, such as lead damage or poor posture. There were nine postoperative seizures and 11 cases of postoperative infection, six of which required removal and/or replacement of a pulse generator. One patient had a generalized tonic-clonic seizure, intracranial infection, shock, and drug coma, among other SAEs.
Additionally, there were six suicide attempts and one completed suicide. Studies have documented five postoperative ICH events, two of which resulted in prolonged finger paralysis and prolonged dysarthria. In two cases, the DBS therapy itself led to a new obsession (such as checking settings and battery life), which worsened the OCD.
The meta-analytic Y-BOCS (MD) mean difference among 345 pooled patients from 31 trials was 14.28 points at the most recent follow-up. The meta-analytic treatment effect (TE) was found to be a 47% decrease in Y-BOCS scores at last follow-up in 249 patients from 28 studies where estimates of precision could be acquired or measured using pre-homogenized results and post-disambiguated data that were available.
The study results showed that DBS is an effective treatment for TROCD, and the typical patient will achieve a 50% reduction in OCD symptoms. With further follow-up, two-thirds of patients will experience at least a complete response to DBS therapy. Additionally, researchers believe that current limbic and non-limbic targets can be stimulated to significantly reduce the comorbid depressive symptoms of TROCD.