Repetitive Transcranial Magnetic Stimulation in the Treatment of depression: A Randomized, Double-blind, Placebo-controlled Trial

Abstract

BACKGROUND: The efficacy of repetitive transcranial magnetic stimulation (rTMS) in the treatment of depression has never been reported as yet in the Indian literature. AIMS: To study the efficacy of rTMS in the treatment of depression and to evaluate its safety and tolerability. SETTINGS AND DESIGN: A randomized, double-blind, sham-controlled trial was conducted at the Department of Psychiatry, National Institute of Mental Health and Neurosciences, Bangalore. MATERIALS AND METHODS: 23 patients with depression were randomized to receive either active (n=9) or sham (n=14) treatment with rTMS. Treatment consisted of six sessions of rTMS for 2 weeks (10 trains of pulses, intensity equal to motor threshold, 10 Hz frequency, train duration of 5 seconds, 1 minute inter-train duration). Response was assessed using Hamilton Depression Rating Scale (HDRS), Montgomery Åsberg Depression Rating Scale (MADRS) and Clinical Global Index (CGI). The safety and tolerability was assessed with side-effect checklist for electroconvulsive therapy. 50% reduction in HDRS scores from baseline was defined as treatment response. Outcome measures were analyzed by repeated measures analysis of variance. Chi-square test was used to analyze the categorical variables. RESULTS: No statistical significance was seen on the baseline socio-demographic and illness characteristics (Pearson's Chi-square=0.5). Although HDRS (sham 22.0-12.4; active 22.8-12.7) and MADRS (sham 30.7-17.3; active 31.8-16.7) scores reduced by the end of 2 weeks treatment, it was not statistically significant. One patient developed manic symptoms early in the treatment. CONCLUSIONS: Treatment with rTMS did not show improvement at the end of 2 weeks. More studies with larger sample size and with higher rTMS dosages need to be done.