Cognitive effects of deep brain stimulation in patients with obsessive–compulsive disorder

Abstract

IntroductionRecently, several studies have shown that deep brain stimulation (DBS) targeting the anterior limbs of the internal capsule, the ventral striatum, the nucleus accumbens (NAcc), the inferior thalamic peduncle and the subthalamic nucleus is effective in patients with treatment-refractory obsessivecompulsive disorder (OCD). [1][2][3][4][5][6][7][8][9] To date, the results of 7 controlled studies have been published worldwide and have reported that 34 of 63 patients experienced a reduction of at least 35% of OCD symptoms. Consequently, half of the treated patients can be considered responders, indicating that DBS is a promising technique. 10Neuropsychological evaluation in DBS treatment plays a vital role in preoperative neuropsychological screening of potential DBS candidates, in evaluation of outcome and in research.11 The contribution of neuropsychological assessment in research is 2-fold: it may establish the cognitive safety of DBS treatment and it may demonstrate whether DBS alters the underlying cognitive deficits in individuals with OCD. Presently, there is evidence that the clinical effectiveness of DBS in patients with OCD is achieved with stable [3][4][5][6][7][8]12,13 and even improved 14 cognitive functioning. However, since small sample sizes, lack of a control group and the use of a limited range of tests hinder the interpretation of the results, the effect of DBS on cognitive functioning in patients with OCD is still unknown.We conducted a prospective, controlled study investigating the cognitive effects of bilateral DBS targeted at the NAcc 3 weeks and 8 months postoperatively to examine its shortand long-term effects. In addition we investigated whether clinical changes after DBS treatment were associated with changes in cognitive functioning. Changes were compared at 3 time points with a matched control group of patients with treatment-refractory OCD who received conventional therapy. Background: Deep brain stimulation (DBS) is a promising treatment for treatment-refractory obsessive-compulsive disorder (OCD). However, the effects of DBS on cognitive functioning remain unclear. Therefore, we aimed to assess cognitive safety of DBS for treatment-refractory OCD and the association between clinical changes and cognitive functioning. Methods: Patients with treatmentrefractory OCD treated with DBS targeted at the nucleus accumbens (NAcc) were compared with a control group of 14 patients with treatment-refractory OCD treated with care as usual. We assessed cognitive functioning at baseline, 3 weeks postoperatively and following 8 months of DBS. We compared change in clinical symptoms with cognitive changes. Results: There were 16 patients in the DBS group and 14 patients in the control group. Three weeks postoperatively, the DBS group showed a significantly reduced performance on measures of visual organization and verbal fluency and a trend toward reduced performance on measures of visual memory and abstract reasoning. Cognitive functioning was found to be stable on all other measures. Afte...

A review of brain stimulation methods to treat substance use disorders

“…Of 10 nicotine‐dependent participants, three quit smoking altogether, while the remaining seven participants demonstrated a significant decline in cravings and consumption. In another study, active DBS significantly reduced craving and consumption of cigarettes in a single subject who originally underwent DBS treatment for refractory OCD.…”

“…There have been two studies investigating the use of DBS on cigarette smoking and nicotine‐dependence targeting the nucleus accumbens. Kuhn et al conducted a study in nicotine craving and cigarette consumption.…”

“…Finally, since most of the published studies were preliminary (with total sample sizes <40), further research in larger patient samples using randomized, sham‐controlled designs are necessary to validate these brain stimulation methods for the treatment of SUDs. Notably, four studies involved the use of participants with a comorbid psychiatric condition . For instance, Wing et al used rTMS in a sample consisting of 15 participants with a primary diagnosis of schizophrenia.…”

“…Furthermore, a study by Ceccanti et al studied participants with co‐occurring dysthymic disorder and alcohol use disorder, with positive results indicating a significant decline in consumption after ten sessions of active rTMS. Finally, Mantione implemented DBS in a woman with treatment refractory OCD. While this effect was unintended, the participant saw a significant decline in craving and consumption of cigarettes after DBS stimulation.…”

The application of deep brain stimulation in the treatment of psychiatric disorders

“…In three patients, discontinuation of stimulation resulted in an acute relapse of depressive symptoms and re-initiation led to a reoccurrence of the antidepressant effect. No negative neurocognitive effects were found in MDD patients following acute or chronic DBS of the NAc or VC/VS (Grubert et al, 2011;Kubu et al, 2016;Mantione, Nieman, Figee, Van Den Munckhof, et al 2014).…”