title: Deep brain stimulation in mental health: Review of evidence for clinical efficacy.
abstract: OBJECTIVE
  There is increasing interest in the use of deep brain stimulation as a treatment for psychiatric disorders. In this review, we consider the evidence for the effectiveness of deep brain stimulation for psychiatric indications, with a primary focus on obsessive compulsive disorder and major depressive disorder.
  
  
  METHODS
  Case reports, case series and clinical trials where deep brain stimulation was primarily utilised in the treatment of a psychiatric disorder, including obsessive compulsive disorder, major depressive disorder, anorexia nervosa or an addictive disorder were identified. The evidence for the effectiveness of deep brain stimulation in the treatment of obsessive compulsive disorder and major depressive disorder was reviewed with studies clustered by the site of implantation.
  
  
  RESULTS
  The majority of identified manuscripts report small case series or single cases. A limited number of studies have reported some form of randomised or blinded stimulation comparison. All of these comparative reports have included small samples of subjects (less than 20 per study in total) compromising the feasibility of making statistical comparison between outcomes in the comparison phases. The two exceptions to this have been industry-sponsored studies conducted in the treatment of major depressive disorder. However, both were stopped prematurely due to concerns about poor efficacy.
  
  
  CONCLUSIONS
  There is insufficient evidence at this point in time to support the use of deep brain stimulation as a clinical treatment for any psychiatric disorder outside of research and programmes where formal outcome data are being systematically collated. While some promising initial data exist to support its potential efficacy for a number of psychiatric conditions, further research is required to establish optimal implantation targets, patient characteristics associated with positive therapeutic outcomes and optimal deep brain stimulation parameters and parameter-programming methods.
authors.affiliation: Monash Alfred Psychiatry Research Centre, Alfred Psychiatry Research Centre, Monash University Central Clinical School and Alfred Health, Melbourne, VIC, Australia paul.fitzgerald@monash.edu.
authors.forename: Paul B
authors.initials: PB
authors.lastname: Fitzgerald
authors.affiliation: Monash Alfred Psychiatry Research Centre, Alfred Psychiatry Research Centre, Monash University Central Clinical School and Alfred Health, Melbourne, VIC, Australia.
authors.forename: Rebecca A
authors.initials: RA
authors.lastname: Segrave
mesh_terms: D046690:Deep Brain Stimulation / Q000379:methods / Q000523:psychology*; D003865:Major Depressive Disorder / Q000628:therapy*; D019317:Evidence-Based Medicine; D006801:Humans; D008603:Mental Health; D009771:Obsessive-Compulsive Disorder / Q000628:therapy*; D011184:Postoperative Period; D016032:Randomized Controlled Trials as Topic; D013406:Suicide, Attempted; D016896:Treatment Outcome
keywords: Deep brain stimulation; depression; obsessive compulsive disorder; psychosurgery; treatment resistance