Augmentation with transcranial direct current stimulation in difficult to treat obsessive-compulsive disorder: A case report

Abstract

Sir, Obsessive-compulsive disorder (OCD) is associated with a lowered life quality and a greater degree of dysfunction in social and occupational functioning.[1] A significant proportion of patients with OCD, are resistant to therapy.[2] Numerous neuromodulation approaches, including deep brain stimulation (DBS), transcranial direct current stimulation (tDCS), and repetitive transcranial magnetic stimulation (TMS), have been utilized in conjunction with conventional pharmacological and psychological treatments.[3] tDCS, a noninvasive form of neurostimulation, has demonstrated a potential role as a safe and successful treatment for OCD in several trials.[2] The orbitofrontal cortex and the supplementary motor area (SMA) are the two most promising stimulation sites.[4] We present a case of a young male suffering from OCD who has a poor response to pharmacological treatment. A young male of 27 years attended the adult psychiatry outpatient department with complaints of recurrent repetitive sexual thoughts, excessive doubts, and repeated checking behavior for 3 years. The patient also had low mood, decreased interest in activities that were previously enjoyable, reduced interaction with friends and family members, disturbed sleep, disturbed sleep, and low confidence. There was no past or family history of any psychiatric or substance use. He was diagnosed with OCD, mixed obsessional thoughts and acts, and moderate depressive episodes. The patient was given an adequate trial on escitalopram (maximum 60mg/day) which was later augmented with ondansetron (8mg/day) and aripiprazole (5mg/day) but had a poor response to treatment. The patient was switched to fluvoxamine (maximum 300mg/day), clomipramine (50 mg), and buspirone (10mg), which were tried for a month, during which the patient had maintained adherence. However, the patient had only minimal response to treatment. Hence, the patient was admitted with a plan to augment the therapy with tDCS. Along with fluvoxamine 300 mg/day, clomipramine 50 mg/day, buspirone 10 mg/day, and tDCS sessions were administered (once daily for the first 10 sessions, followed by twice daily for the subsequent ten sessions). A 2-mA current was used with a ramp time of 20 s. The total duration of the session was 20 min and 40 s. Anode placement was done over SMA to target OC symptoms and cathode over the right dorsolateral prefrontal cortex (DLPFC) to target the depressive symptoms, concurrently. After 20 sessions, there was a significant reduction in YBOCS scores up to 46.4%, i.e., from an initial score of 28/40 to 15/40. Similarly, the HAM-D score changed from the initial score of 17/50 to 6/50 (64.7% reduction from the baseline severity score). The benefit was sustained for the next 4 months during the follow-up. Augmentation with tDCS can be effective for severely ill OCD patients unresponsive to drugs and behavioral therapy. Among the various types of obsessions, sexual obsessions are considered to be relatively resistant to treatment. In our case, the sexual obsessions responded well to tDCS augmentation. The patient did not report any major side effects, other than mild headaches following the initial few sessions. DBS and TMS received the most evidence, while for tDCS, evidence is less as of now.[5] However, studies in this area are few, and a well-defined protocol is lacking regarding the frequency of sessions, number of sessions, electrode placement, and the target brain areas. Hence, more RCTs in this area will help to increase the armamentarium in the treatment of resistant OCD. As a large number of patients with OCD often have comorbid depressive episodes, placement of anode over SMA and placement of cathode over the right DLPFC may be helpful in treating both conditions concurrently. Declaration of patient consent The authors certify that they have obtained all appropriate patient consent forms. In the form the patient (s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.