Deep Brain Stimulation and Obsessive-compulsive Disorder
Condition: Obsessive-Compulsive Disorder
MeSH terms: Compulsive Personality Disorder; Obsessive-Compulsive Disorder
Study type: Interventional
Phase: Phase 3

Summary: 
      Obsessive-compulsive disorder (OCD) is a relatively common psychiatric condition, which is
      classically treated by antidepressant medications in combination with psychotherapies.
      However, both these conventional therapeutic approaches fail to sufficiently improve
      obsessive-compulsive symptoms in 20-30% of cases. From these considerations, deep brain
      stimulation (DBS), as a reversible and adjustable surgical procedure, has recently been
      introduced in the field of resistant OCD. DBS currently uses electrodes with four contacts on
      each lead, which are bilaterally implanted into the chosen brain structure. DBS consists of
      the delivery of a high-frequency current through the quadripolar electrodes connected to a
      battery powered pulse-generating device. Several clinical investigations have shown that DBS,
      primarily targeting either the ventral striatum (VS) or the subthalamic nucleus (STN), as
      brain sites of interest because of their particular involvement in the production of OCD
      symptoms, is able to produce an approximately 40% or greater reduction in clinical symptom
      intensity in severely chronic and incapacitating forms of OCD. These promising findings lead
      to propose a comparison of the efficacy, safety and tolerability of DBS choosing either the
      VS or STN as brain target by conducting a large controlled trial and including a
      medico-economic analysis for assessing the classical cost/efficacy ratio. In this way, the
      present study is expected to promote and highlight the importance of DBS, as an effective,
      safe, well-tolerated and cost-relevant surgical approach for the management of resistant OCD.
    

Detailed description: 
      Obsessive-compulsive disorder (OCD) is a relatively common psychiatric condition with an
      estimated lifetime prevalence of 2-3 % of the general population. It is generally
      characterized by a chronic course leading to a profound impairment in psychosocial
      functioning and to a marked deterioration in quality of life. Today, the well-established
      efficacy of antidepressants, acting preferentially by blocking serotonin reuptake, in
      addition to psychological treatments, have considerably changed the poor prognosis of the
      illness. However, both conventional therapeutic approaches failed to substantially alleviate
      obsessive-compulsive symptoms in 20-30% of cases. Deep brain stimulation, as a reversible and
      adjustable surgical procedure, has recently been introduced in the field of OCD, primarily
      targeting either the ventral striatum (VS) or the subthalamic nucleus (STN) and leading to an
      approximately 40% or greater reduction in clinical symptom intensity from baseline levels in
      severely chronic and resistant forms of OCD. These promising findings lead to propose a
      comparison of the efficacy, safety and tolerability of DBS choosing either the VS or STN as
      brain target by conducting a multicenter, parallel-group, randomized, single-blind trial over
      a 13-month follow-up period. For this purpose, a total population of 28 OCD patients who meet
      the currently used operational criteria for defining therapeutic resistance will be
      recruited. The surgical procedure will consist in the implantation of stimulation electrodes
      with four contacts on each lead, which are stereotactically and bilaterally implanted into
      the targeted brain structure under local anesthesia. Per-operative, single-unit
      electrophysiological recordings of the neuronal activity will be performed using five
      parallel microelectrodes and serving as guide for the implantation of both definitive
      electrodes. They will be connected to a battery powered pulse-generating device five days
      later under general anesthesia. Thereafter, psychiatric assessments including both the Y-BOCS
      ("Yale-Brow Obsessive-compulsive scale") and PI ("Padua Inventory") for measuring OCD symptom
      severity, the BAS ("Brief Anxiety Scale"), MADRS ("Montgomery and Asberg Depression rating
      Scale") and HAD ("Hospital Anxiety and Depression Scale") for determining anxiety and/or
      depressive symptom intensity, and the CGI ("Clinical Global Impression") rating scales for
      evaluating global symptom severity and treatment response will be performed every 3 months
      beyond the one-month postoperative free-stimulation period. This will be coupled with a large
      battery of neuropsychological tests exploring all executive functions in combination with
      precise medical records of side effects for appreciating safety/tolerability of DBS. A
      cost-effectiveness analysis, as a formal method of comparing DBS and classical therapeutic
      strategies with regard to their respective resource utilization (costs) and outcomes
      (effectiveness) will also be carried out. Therefore, the present study may contribute to
      highlight the special interest of DBS, as an effective, safe, well-tolerated and
      cost-relevant surgical approach for the management of resistant OCD.
    

Intervention name(s): Deep Brain Stimulation (DBS)
Intervention type(s): Procedure
Intervention description(s): In a first time: Implantation of DBS electrodes, stereotactically, in each hemisphere into the targeted brain structure under local anesthesia. In a second time (next week): installation of the deep brain neurostimulator and connection to the electrodes implanted under general anesthesia. And one month later: beginning of the stimulation.
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Single (Outcomes Assessor)
Primary purpose: Treatment
Keywords: Deep brain stimulation (DBS); Obsessive compulsive disorder; ventral striatum; subthalamic nucleus