Assessing the Pharmacotherapy and Clinical Outcomes After Deep Brain Stimulation for Treatment-Refractory Obsessive–Compulsive Disorder: A Case–Cohort Study

Background: In the search for effective treatments for refractive obsessive–compulsive disorder (OCD), deep brain stimulation (DBS) serves as an alternative option for those with minimal response to pharmacotherapy. The rarity of reports regarding DBS use for OCD is attributed to the invasive nature of the procedure: placement of electrodes within targeted areas of the brain to provide neuromodulation. This treatment of last resort may decrease functional impairment and pharmacologic complications for a debilitating mental illness. This study compares the pharmacotherapy utilization and treatment outcomes of five treatment-refractory OCD patients after the placement of DBS with those of a matched cohort. Methods: This retrospective, single-center, case–cohort study reviewed the electronic medical records of five subjects treated with DBS for treatment-refractory OCD and compared them to a similar treatment-refractory cohort whose OCD was treated without the use of DBS. Control subjects were matched by age, sex, years since diagnosis, number of previous medication class trials, and additional clinical factors. Inclusion criteria were defined as those that are at least eighteen years of age, assigned a primary diagnosis of OCD per the ICD-10 classification, and received DBS treatment for refractory OCD. Exclusion criteria included comorbid psychotic disorders, unstable neurological or coagulation disorder(s), and/or an eating disorder diagnosis. The primary endpoint was the change in the number of psychotropic medications two years after implantation for the DBS cohort and two years after psychiatric decompensation for the comparator cohort. Secondary endpoints included: Y-BOCS (the Yale–Brown Obsessive–Compulsive Scale) changes over time, duration quantity of psychotropic medication classes prescribed, and additional symptomology scale changes. Results: Patients receiving DBS were more likely to be on fewer medications and trialed fewer medications after treatment. One out of the five patients was found to be a responder in Y-BOCS scoring after DBS treatment. A reduction in anxiety and depression symptoms was also seen in the HAM-A and HAM-D scales for those that received DBS. Conclusions: A reduction in psychiatric medications trialed during therapy was observed, as well as varying reductions in OCD, anxiety, and depression symptomology following DBS. Results from this study indicate that DBS implantation may contribute to a reduction in polypharmacy while displaying DBS’s potential impact on comorbid anxiety and depression symptoms. Given that the small sample size limits generalizability, additional prospective, randomized trials comparing the efficacy of DBS for OCD-specific symptomology and its overall impact on pharmacotherapy are needed in order to further establish the role of DBS as an accepted treatment option for OCD.