Effectiveness of Repetitive Transcranial Magnetic Stimulation in Depression, Schizophrenia, and Obsessive-Compulsive Disorder: An Umbrella Meta-Analysis

Objective: To analyze the safety and efficacy of repetitive transcranial magnetic stimulation (rTMS) for major depressive disorder, schizophrenia, and obsessive-compulsive disorder (OCD) via umbrella meta-analysis. Data Sources: Meta-analysis studies were searched in PubMed PubMed from inception to May 2021 using the keywords anxiety, depression, ADHD, schizophrenia, mood disorder, OCD, psychiatric disorders, GAD, bipolar disorders, ASD, PTSD, transcranial magnetic stimulation, transcranial, magnetic, stimulation. PRISMA guidelines were followed. Study Selection: Abstracts and full-length articles were reviewed for meta-analysis studies with data on the safety and efficacy of rTMS and sham and were collected for quantitative analysis. The full texts of all identified studies were independently screened and assessed to determine eligibility. Any disagreement was resolved through consensus. Data Extraction: The descriptive variables extracted included the author names, study year, sample size, studies included in the meta-analysis, study period, and type of intervention. Results: 28 meta-analyses were included; 13 were on treatment-resistant depression, 9 on schizophrenia, and 6 on OCD. In treatment-resistant depression, the rTMS group had higher odds of response compared to sham (odds ratio [OR] = 3.27; 95% CI, 2.76–3.87; P < .00001) and higher odds of remission (secondary outcome) (OR = 2.83; 95% CI, 2.33–3.45; P < .00001). rTMS was superior to sham in the reduction of negative symptoms of schizophrenia (mean difference [MD]: 0.47; 95% CI, 0.23–0.7; P < .0001). However, no significant difference was found between the effects of rTMS and sham on auditory hallucinations (MD: 0.24; 95% CI, 0.26–0.74; P = .35), which resulted in 94% heterogeneity. TMS was better than sham in reducing the severity of OCD symptoms (MD: 0.81; 95% CI, 0.53–1.10; P < .00001). Conclusions: The effectiveness of rTMS for symptom reduction in various psychiatric disorders is associated with differences in neuropathology, disease-specific target site, and frequency of rTMS.