Evidence-based umbrella review of non-invasive brain stimulation in anxiety disorders

Background and objectives: Although several meta-analyses have suggested the efficacy of noninvasive brain stimulation (NIBS) mainly in prefrontal brain areas to treat mental disorders, no synthetic approach has been performed for other psychiatric disorders rather than depression. The objective is to assess the available evidence of NIBS in the treatment of anxiety disorders. Methods: An umbrella review (CRD42021239577) was performed only looking for reviews with meta-analyses of randomized clinical trials using a source strategy MeSH keywords in MEDLINE through Pubmed by two independent researchers. The effects of different methods of NIBS in anxiety disorders were assessed using the PICO strategy. The methodological quality was evaluated using AMSTAR-2 and certainty of evidence using the GRADE-pro framework. Results: From 136 screening meta-analyses, 16 from 14 studies were included in the final analysis. Generalized Anxiety Disorder (GAD) and Obsessive Compulsive Disorder (OCD) respond best to low frequency repetitive transcranial magnetic stimulation (rTMS), while Posttraumatic Stress Disorder (PTSD) has the largest effect size at high frequency rTMS. Panic Disorder (PD) has no evi-dence for clinical use of NIBS. There were not identified meta-analyses about other anxietydisorders. In general, the included studies had good methodological quality, but low to moderate evidence for clinical recommendation. Conclusion: Available evidence reveals NIBS as an effective and safe approach to treat GAD, PTSD and OCD with low recommendation level to clinical application. A great heterogeneity of studies indicates the necessity to develop new randomized clinical trials applying NIBS to treat those and other mental disorders. \& COPY; 2023 Asociacion Universitaria de Zaragoza para el Progreso de la Psiquiatria y la Salud Mental. Published by Elsevier Espana, S.L.U. All rights reserved.

Automated summary

This study conducted an umbrella review to assess the available evidence of noninvasive brain stimulation (NIBS) in the treatment of anxiety disorders. The results showed that low-frequency repetitive transcranial magnetic stimulation (rTMS) is most effective for generalized anxiety disorder (GAD) and obsessive-compulsive disorder (OCD), while high-frequency rTMS has the largest effect size for posttraumatic stress disorder (PTSD). There is no evidence supporting the clinical use of NIBS for panic disorder (PD). Overall, NIBS is considered an effective and safe approach for treating GAD, PTSD, and OCD.