Effectiveness of transcranial direct current stimulation (tDCS) treatment in Obsessive Compulsive Disorder.

Recruiting

• Conditions: Obsessive Compulsive Disorder(OCD)

• Registration Number: CTRI/2016/04/006837
• Lead Sponsor: Department of Psychiatry National Institute of Mental Health and Neurosciences

Brief Summary

BACKGROUND

Obsessive compulsive Disorder (OCD) is a common and often debilitating anxiety disorder with a chronic, sometimes life-long course. OCD is characterized by recurrent, intrusive, anxiety-provoking thoughts called the obsessions and the compulsive/neutralising behaviours aimed at reducing distress or preventing dreaded events. Selective Serotonin Reuptake Inhibitors (SSRIs) form the mainstay of treatment for this condition . However, nearly 40 to 60 % of patients do not respond satisfactorily to SSRIs . Thus, treatment resistance is a very common phenomenon leading to significant treatment burden.

In neuropsychological studies of OCD, the consistent deficits that emerge can be broadly classified as memory & executive function deficits and emotion & reward system deficits. Deficits in non-verbal memory and certain executive functions have been widely reported in OCD . The neuropsychological deficits in OCD suggest abnormalities in specific brain circuits namely the fronto-striato-pallido-thalamo frontal loop. These are the brain regions involved in the important cognitive functions postulated to be abnormal in OCD response inhibition, error monitoring and executive functioning . This consists of a series of parallel segregated frontal-subcortical circuits now known to link specific regions of the frontal cortex to the striatum, the globus pallidus and substantia nigra, and the thalamus. Congruent with the neurocognitive findings, the structural imaging studies have pointed involvement of areas in the fronto-subcortical region as well as some other posterior areas in OCD as neurobiological substrates . Consistently in structural MRI studies, it has been shown that there are deficits involving the orbitofrontal cortex (OFC) , cingulated cortex as well as striatal regions in OCD compared to control subjects. A VBM study from our centre in drug naïve sample also implicated right ACC as a key region which differentiated OCD patients from controls. Additionally, caudate volume abnormalities were also demonstrated in drug naïve OCD subjects using a region of interest (ROI) paradigm.

 Need for the study:

Deficient response inhibition, a critical neurocognitive deficit in OCD, has been found to have its substrate in pre-supplementary and Supplementary Motor Areas (pre-SMA/SMA). Pre-SMA has a regulatory â€œbrake†effect on the striatal functioning. Lack of pre-SMA inhibition on the striatal function could result in striatal hyperactivity which underlies OCD pathogenesis. In OCD, hypoactive pre-SMA correlated with deficient response inhibition and symptom severity. Given its superficial location, pre-SMA/SMA is an attractive target for therapeutic neuromodulation by non-invasive brain stimulation. Previous transcranial magnetic stimulation (TMS) studies of pre-SMA/SMA have shown mixed results in OCD. Transcranial Direct Current Stimulation (tDCS) is a safe, non-invasive, neuromodulatory technique that applies weak direct current through the scalp. Anodal tDCS of pre-SMA/SMA has been shown to enhance inhibitory control in healthy subjects. Recently, the first demonstration of successful application of add-on tDCS for SSRI-resistant OCD leading to significant clinical improvement has been reported from NIMHANS. In this, 2 patients with treatment refractory OCD were given add-on tDCS with anodal stimulation of pre-SMA/SMA. There was significant improvement in OCD- 40% and 52% reduction in YBOCS rating respectively. The clinical improvement has persisted after tDCS sessions till the latest follow-up (2-months and 1 month) as per the report. Based on this previous report and the literature on the role of preSMA/SMA, this study has been proposed to examine the efficacy of anodal tDCS on preSMA/SMA in participants with OCD.

 OBJECTIVES:

The aim of the study is to examine the efficacy of tDCS in OCD patients with persistent symptoms using a double blind randomised sham controlled design.

The effect of tDCS on the neurocognitive function- error monitoring/response inhibition would be examined in comparison to healthy volunteer as controls for ascertaining the comparative profile of inhibitory function using stop signal task.

 HYPOTHESES:

OCD patients will demonstrate significantly deficient response inhibition in comparison with matched healthy controls,There will be a significant reduction in severity of obsessive compulsive symptom as well as deficient response inhibition in patients with add on tDCS treatment.

Reduction in OC symptom severity will have significant positive correlation with improvement in the response inhibition cognitive function.

Detailed Description

Not available

Study Timeline

• Study Start: 2015-01-12
• Last Update Posted: 2016-04-19

Recruitment & Eligibility

• Status: Open to Recruitment
• Sex: All
• Target Recruitment: 35

Inclusion Criteria

1)Diagnosis of Obsessive Compulsive Disorder (OCD)as per DSM-V criteria (Diagnostic and Statistical Manual for Mental Disorders, American Psychiatric Association, 2013) 2)If the participants are on medications, they would need to be on stable dose of SSRI for atleast 3 months 3)Clinically Significant OCD as evidenced by a cut-off YBOCS severity score of ≥16 Age range: 18 – 45 years; 6) Both sexes; 7) Right Handedness and 8) Written informed consent.

Exclusion Criteria

1. Features suggestive of psychiatric emergency (for example: suicidal risk, aggression, excitement, catatonia, prolonged nutritional deprivation or any other status requiring intensive clinical care), 2) Any contraindication to tDCS procedure – (i) metallic implants in the head, (ii) implanted brain medical devices, (iii) local lesion or injury in the scalp / head, 3) Co-morbid psychiatric diagnoses such as psychosis, bipolar disorder, substance dependence (including nicotine dependence) 4) Mental retardation, neurological disorders and other organic brain disorders 5) Left Handedness.

Study & Design

• Study Type: Interventional
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
Degree(Severity) of Obsessive and compulsive symptoms	Daily before next tDCS sessions

Secondary Outcome Measures

Name	Time	Method
Cognition	Twice. Before intervention and after intervention

Trial Locations

Locations (1)

Biolab B block ground floor special ward block,Department of psychiatry, NIMHANS; 🇮🇳 Bangalore, KARNATAKA, India

Biolab B block ground floor special ward block,Department of psychiatry, NIMHANS

🇮🇳Bangalore, KARNATAKA, India

Shayanth

Principal investigator

9738782373

rushtoshayanth@gmail.com