rTMS Safe, Effective for Depression and Psychosis Should We Expand the Toolbox of Psychiatric Treatment Methods to Include Repetitive Transcranial Magnetic Stimulation (rTMS)? A Meta-Analysis of the Efficacy of rTMS in Psychiatric Disorders

Background: Repetitive transcranial magnetic stimulation (rTMS) is a stimulation therapy approved by the Food and Drug Administration in 2008 for the treatment of depression. However, its use remains obscure. Objective: To determine whether rTMS should be brought out of obscurity for the treatment of depression, schizophrenia, and obsessive-compulsive disorder (OCD). Design: A meta-analysis of rTMS for the management of mood and anxiety disorders, psychosis, attentiondeficit/hyperactivity disorder (ADHD), Tourette syndrome, bulimia nervosa, and addiction. Participants/Methods: A literature search was conducted to identify parallel, double-blind, randomized, controlled studies investigating rTMS published between 1966 and 2008. Only those psychiatric disorders investigated in at least 3 studies were included in the meta-analysis. Effect sizes were calculated for mean differences in pretreatment versus posttreatment rating scales with rTMS compared to sham treatment. Results: The only psychiatric conditions for which rTMS had been studied sufficiently for meta-analysis were depression, psychosis with auditory verbal hallucinations (AVH), psychosis with negative symptoms, and OCD. Studies investigating rTMS for depression had varied methodologies, and they tested rTMS monotherapy, adjunctive therapy with medication, and cotherapy with medication. rTMS was also compared to electroconvulsive treatment (ECT) in 6 studies of major depression. For depression, rTMS monotherapy performed best (effect size, 0.96) followed by adjunctive treatment (effect size, 0.51) and simultaneous cotherapy with an antidepressant (effect size, 0.37). rTMS for depression was applied over the right or left dorsolateral prefrontal cortex (DLPF), although the location of stimulation did not significantly affect performance of rTMS. rTMS was less effective than ECT for severe major depression, with a weighted effect size of -0.47. In 7 randomized controlled trials, rTMS applied to the left temporoparietal cortex was moderately effective for the treatment of AVH (effect size, 0.54). rTMS was also mildly effective for the treatment of negative symptoms of psychosis in 7 studies (effect size, 0.39). Most of these studies applied rTMS over the left DLPF. In contrast, rTMS was not effective for the treatment of OCD in 3 studies (effect size, 0.15; n=38). Conclusions: Based on these meta-analyses, rTMS should be considered standard treatment for major depression and for both positive and negative symptoms of psychosis that are refractory to pharmacotherapy. rTMS appears to be more effective as monotherapy instead of as adjunctive therapy for major depression. The authors do not recommend the use of rTMS for OCD. Reviewer's Comments: Most participants in these studies were resistant to pharmacotherapy, but it was prudent and cost-effective to try antidepressant or antipsychotic therapy before initiating rTMS treatment for depression and psychosis, respectively. Future studies need to determine the longevity of benefit from rTMS. (Reviewer-Charlotte O. Ladd, MD, PhD).