Background and significance: Deep brain stimulation (DBS) of the anterior limb of the internal capsule and nucleus accumbens has recently been used as treatment for severe, chronic and resistant obsessive compulsive disorder (OCD). Findings on efficacy, tolerability and effectiveness of deep brain stimulation in treatment resistant OCD are promising but numerically limited or anecdotic. Moreover, published long-term outcome data are even more limited. Objectives: Aim of the present report is to review and to summarize the current investigational status of deep brain stimulation in OCD. Methods: This study reviewed only the clinical literature related to DBS in OCD, not preclinical studies. Results: Available data on the short-term efficacy on chronic, severe and resistant OCD symptoms are numerically limited but consistent. Nonetheless, they still have a low impact on clinical practice, mainly on account of six important limitations: 1) the technique is invasive; 2) the small size of samples in which DBS has been tested; 3) the heterogeneity of clinical presentation of OCD patients treated with DBS; 4) the limited number of long-term observations. Few studies have attempted to examine the chronic effects of DBS, or habituation of responses; 5) finding of mood changes and hypomania induced by DBS. Hypomanic switches could be related to the activation of neuronal pathways between the anterior limb of the internal capsule, the nucleus accumbens and the orbital and medial prefrontal cortex and/or cingulate gyrus; 6) the induction of fear and panic responses. In particular, DBS in the region of the nucleus accumbens has been described as triggering panic-like attacks. Obviously, DB stimulation parameters can be modified or DBS can be discontinued if side-effects occur. Concluding remarks: Available findings are concordant as far as concerns mid-term clinical response of resistant obsessions and compulsions to DBS. However, these studies provide only a "snapshot" of the efficacy and effectiveness of DBS. Additional long-term, controlled studies are needed to demonstrate DBS efficacy in treatment of resistant OCD more conclusively. Further investigations are also required to better understand the mechanisms of clinical response to DBS, and to address other important issues, such as the potential relevance of acute responses to predict clinical effects in follow-up studies, and the need for more refined selection criteria of patients. In our opinion, the occurrence of hypomania or panic attacks, triggered or induced by DBS, in patients with OCD, could be significantly reduced with a psychopathological assessment encompassing not only the Axis I lifetime or current co-morbidity for bipolar or panic disorder, but also their sub-threshold, or sub-syndromal manifestations.
|Translated title of the contribution||Deep brain stimulation (DBS) in treatment-resistant chronic obsessive-compulsive disorder: A critical review|
|Number of pages||7|
|Journal||Italian Journal of Psychopathology|
|Publication status||Published - Sep 2007|
ASJC Scopus subject areas
- Psychiatry and Mental health