Efficacy and safety of transcranial direct current stimulation (tDCS) in patients with obsessive-compulsive disorder (OCD): A systematic review and meta-analysis of randomized controlled trials.

Background: Transcranial direct current stimulation (tDCS) is gaining traction for treating obsessive-compulsive disorder (OCD), but its effectiveness and safety remain uncertain. A systematic review of randomized controlled trials (RCTs) will assess its clinical benefits for symptom reduction.

Methods: Six databases-Scopus, PubMed, Web of Science, Cochrane, PsycINFO, and Cochrane Central-were searched to identify relevant studies. The included studies were RCTs that assessed the effects of tDCS on OCD symptoms, as well as its impact on anxiety and depression, while also evaluating adverse events (AEs). The risk of bias (ROB) was analyzed using the ROB-2 tool. A meta-analysis was performed utilizing Stata-17 software.

Results: Immediately following treatment, the analysis revealed that tDCS significantly reduced the Y-BOCS score (SMD = -0.56 [-0.87, -0.26]), anxiety scores (SMD = -1.11 [-1.85, -0.37]), and depression scores (SMD = -1.57 [-2.64, -0.50]), while increasing CGI-S scores (SMD = 0.40 [0.08, 0.72]) in OCD patients compared to the sham group. During the follow-up period (1-2 months post-treatment), tDCS continued to decrease the Y-BOCS score (SMD = -0.69 [-1.22, -0.17]), anxiety scores (SMD = -1.13 [-3.05, -0.78]), and depression scores (SMD = -2.02 [-3.00, -1.04]), but showed no effect on CGI-S scores when compared to the sham group. Additionally, the analysis indicated no significant differences in AEs between active tDCS and the sham group (OR: 1.20 [0.86, 1.68]).

Conclusions: This review suggests that tDCS may effectively alleviate OCD symptoms, along with related depression and anxiety, both acute and at follow-up, while causing minimal AEs.