Feasibility, acceptability and practicality of transcranial stimulation in obsessive compulsive symptoms (FEATSOCS): A randomised controlled crossover trial.

Transcranial direct current stimulation (tDCS) is a non-invasive form of neurostimulation with potential for development as a self-administered intervention. It has shown promise as a safe and effective treatment for obsessive compulsive disorder (OCD) in a small number of studies. The two most favourable stimulation targets appear to be the left orbitofrontal cortex (L-OFC) and the supplementary motor area (SMA). We report the first study to test these targets head-to-head within a randomised sham-controlled trial. Our aim was to inform the design of future clinical research studies, by focussing on the acceptability and safety of the intervention, feasibility of recruitment, adherence to and tolerability of tDCS, and the size of any treatment-effect. FEATSOCS was a randomised, double-blind, sham-controlled, cross-over, multicentre study. Twenty adults with DSM-5-defined OCD were randomised to treatment, comprising three courses of clinic-based tDCS (SMA, L-OFC, Sham), randomly allocated and delivered in counterbalanced order. Each course comprised four 20-min 2 mA stimulations, delivered over two consecutive days, separated by a 'washout' period of at least four weeks. Assessments were carried out by raters who were blind to stimulation-type. Clinical outcomes were assessed before, during, and up to four weeks after stimulation. Patient representatives with lived experience of OCD were actively involved at all stages. Clinicians showed willingness to recruit participants and recruitment to target was achieved. Adherence to treatment and study interventions was generally good, with only two dropouts. There were no serious adverse events, and adverse effects which did occur were transient and mostly mild in intensity. Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) scores were numerically improved from baseline to 24 h after the final stimulation across all intervention groups but tended to worsen thereafter. The greatest effect size was seen in the L-OFC arm, (Cohen's d = -0.5 [95% CI -1.2 to 0.2] versus Sham), suggesting this stimulation site should be pursued in further studies. Additional significant sham referenced improvements in secondary outcomes occurred in the L-OFC arm, and to a lesser extent with SMA stimulation. tDCS was acceptable, practicable to apply, well-tolerated and appears a promising potential treatment for OCD. The L-OFC represents the most promising target based on clinical changes, though the effects on OCD symptoms were not statistically significant compared to sham. SMA stimulation showed lesser signs of promise. Further investigation of tDCS in OCD is warranted, to determine the optimal stimulation protocol (current, frequency, duration), longer-term effectiveness and brain-based mechanisms of effect. If efficacy is substantiated, consideration of home-based approaches represents a rational next step. ISRCTN17937049. https://doi.org/10.1186/ISRCTN17937049.

Fineberg NA ，Cinosi E ，Smith MVA ，Busby AD ，Wellsted D ，Huneke NTM ，Garg K ，Aslan IH ，Enara A ，Garner M ，Gordon R ，Hall N ，Meron D ，Robbins TW ，Wyatt S ，Pellegrini L ，Baldwin DS ... -  《-》

Feasibility and acceptability of transcranial stimulation in obsessive-compulsive symptoms (FEATSOCS): study protocol for a randomised controlled trial of transcranial direct current stimulation (tDCS) in obsessive-compulsive disorder (OCD).

Obsessive-compulsive disorder (OCD) is a neuropsychiatric disorder which often proves refractory to current treatment approaches. Transcranial direct current stimulation (tDCS), a noninvasive form of neurostimulation, with potential for development as a self-administered intervention, has shown potential as a safe and efficacious treatment for OCD in a small number of trials. The two most promising stimulation sites are located above the orbitofrontal cortex (OFC) and the supplementary motor area (SMA). The aim of this feasibility study is to inform the development of a definitive trial, focussing on the acceptability, safety of the intervention, feasibility of recruitment, adherence and tolerability to tDCS and study assessments and the size of the treatment effect. To this end, we will deliver a double-blind, sham-controlled, crossover randomised multicentre study in 25 adults with OCD. Each participant will receive three courses of tDCS (SMA, OFC and sham), randomly allocated and given in counterbalanced order. Each course comprises four 20-min stimulations, delivered over two consecutive days, separated by at least 4 weeks' washout period. We will collect information about recruitment, study conduct and tDCS delivery. Blinded raters will assess clinical outcomes before, during and up to 4 weeks after stimulation using validated scales. We will include relevant objective neurocognitive tasks, testing cognitive flexibility, motor disinhibition, cooperation and habit learning. We will analyse the magnitude of the effect of the interventions on OCD symptoms alongside the standard deviation of the outcome measure, to estimate effect size and determine the optimal stimulation target. We will also measure the duration of the effect of stimulation, to provide information on spacing treatments efficiently. We will evaluate the usefulness and limitations of specific neurocognitive tests to determine a definitive test battery. Additionally, qualitative data will be collected from participants to better understand their experience of taking part in a tDCS intervention, as well as the impact on their overall quality of life. These clinical outcomes will enable the project team to further refine the methodology to ensure optimal efficiency in terms of both delivering and assessing the treatment in a full-scale trial. ISRCTN17937049 . (date applied 08/07/2019). Recruitment (ongoing) began 23rd July 2019 and is anticipated to complete 30th April 2021.

Cinosi E ，Adam D ，Aslan I ，Baldwin D ，Chillingsworth K ，Enara A ，Gale T ，Garg K ，Garner M ，Gordon R ，Hall N ，Huneke NTM ，Kucukterzi-Ali S ，McCarthy J ，Meron D ，Monji-Patel D ，Mooney R ，Robbins T ，Smith M ，Sireau N ，Wellsted D ，Wyatt S ，Fineberg NA ... -  《-》

Efficacy of pre-supplementary motor area transcranial direct current stimulation for treatment resistant obsessive compulsive disorder: A randomized, double blinded, sham controlled trial.

A significant proportion of obsessive compulsive disorder (OCD) patients do not respond to specific serotonin reuptake inhibitors (SSRIs). There is a need to evaluate novel treatment options for OCD. In this double blinded, randomized, sham controlled study, we investigated the efficacy of add-on transcranial direct current stimulation (tDCS) in reducing the symptoms in SSRI-resistant OCD patients by employing anodal pre-supplementary motor area (pre-SMA) stimulation. Twenty-five patients with DSM-IV OCD having persistent symptoms despite adequate and stable treatment with at least one SSRI were randomly allocated to receive 20 min of verum (active) 2-mA tDCS or sham stimulation twice daily on 5 consecutive days [anode over Pre-SMA; cathode over right supra-orbital area]. Response to treatment was defined as at least 35% reduction in the Yale-Brown Obsessive-Compulsive Scale (YBOCS) total score along with a Clinical Global Impression - Improvement (CGI-I) score of 1 (very much improved) or 2 (much improved). The response rate was significantly greater in the verum tDCS(4 out of 12) compared to sham-tDCS (0 out of 13) [Fisher's exact test, p = 0.04]. Repeated measures analysis of variance with tDCS type (verum vs. sham) as between subjects factor showed that there was a significant tDCS-type X time-point interaction with significantly greater reduction of YBOCS total score [F (1,22) = 4.95,p = 0.04,partial-η2 = 0.18] in verum-tDCS group. The results of this RCT suggest that tDCS may be effective in treating SSRI-resistant OCD. Future studies should examine the efficacy in larger samples of OCD and explore other potential target regions using randomized sham-controlled designs, in addition to examining the sustainability of the beneficial effects. Clinical Trials Registry India (http://ctri.nic.in/Clinicaltrials/login.php): Registration Number- CTRI/2016/04/006837).

Gowda SM ，Narayanaswamy JC ，Hazari N ，Bose A ，Chhabra H ，Balachander S ，Bhaskarapillai B ，Shivakumar V ，Venkatasubramanian G ，Reddy YCJ ... -  《-》

The safety and efficacy of transcranial direct current stimulation as add-on therapy to fluoxetine in obsessive-compulsive disorder: a randomized, double-blind, sham-controlled, clinical trial.

Yoosefee S ，Amanat M ，Salehi M ，Mousavi SV ，Behzadmanesh J ，Safary V ，Yoonesi A ，Salehi B ... -  《BMC Psychiatry》

The effect of transcranial direct current stimulation (tDCS) on cerebellum in reduction of the symptoms of obsessive-compulsive disorder.

Akbari S ，Hassani-Abharian P ，Tajeri B 《-》