A single-blind, randomized controlled trial of transcranial direct current stimulation in adults with obsessive-compulsive disorder as early augmentation

Abstract Background Transcranial direct current stimulation (tDCS) has emerged as a promising neuromodulation technique for managing obsessive-compulsive disorder (OCD). Early intervention with tDCS may lead to improved treatment outcomes for individuals with OCD, offering hope for more effective and timely intervention strategies. This study aimed to evaluate the safety and efficacy of tDCS as an early augmentation strategy in adults with OCD. Methods Drug-free adult patients with OCD were randomized into active and sham groups and received fluoxetine 20 mg (up to 60 mg). The protocol involved placing the cathode over the left supplementary motor area and the anode over the left dorsolateral prefrontal cortex, using a 2-mA current for 20 minutes, with a ramp time of 10 seconds. A total of 10 sessions were given over 2 weeks. Following the baseline assessment, both illness severity and side effects were measured periodically at 2, 4, and 6 weeks. Results A total of 40 patients completed this study (20 in each group). The active group demonstrated a significant reduction in Yale-Brown Obsessive-Compulsive Scale scores at 2, 4, and 6 weeks compared with the sham group, with a number needed to treat of 2.5. Additionally, the effect size of the intervention at 2 weeks was calculated to be 0.58, indicating a moderate effect according to Cohen’s d. Side effects were milder, tolerable, and uncommon. Conclusion Early augmentation with tDCS is a safe and effective method for rapidly reducing symptom severity in adult patients with OCD.