Effectiveness of Transcranial Direct Current Stimulation on Worry, Anxiety, and Depression in Generalized Anxiety Disorder: A Randomized, Single-Blind Pharmacotherapy and Sham-Controlled Clinical Trial

Abstract

Background: Due to low adherence to treatment and side effects of pharmacotherapy, using new brain stimulation, such as transcranial direct current stimulation (tDCS) in patients with anxiety disorders are available. Objectives: The present research was performed to evaluate the efficacy of tDCS and compare it with pharmacotherapy on reduction of worry, depression, and anxiety in a group of Iranian patients with generalized anxiety disorder (GAD). Methods: This study was a quasi-experimental research. A total of 18 patients (46% females and 64% males) with GAD were randomly assigned either to tDCS, pharmacotherapy or sham conditions. Stimulation was delivered over the contralateral deltoid at 2 m/A during 20 minutes in 10 sessions of 4 weeks. Symptoms were assessed by a 7-item GAD scale, HARS, HDRS, and PSWQ in pre-test, post-test and follow up assessment (2 months later). Analysis of variance with repeated measure was used to analyze the data. Results: The results showed that both tDCS and pharmacotherapy were effective in reducing worry symptoms, also the pharmacotherapy group compared with the tDCS group and sham condition was more effective in treating of worry. Anxiety symptoms were reduced by both tDCS and pharmacotherapy and the difference between the 2 methods was not significant. Finally, the effectiveness of tDCS therapy on reducing depressive symptoms was more significant than pharmacotherapy. Conclusions: The tDCS is a promising treatment for generalized anxiety disorder, especially in depressive and worry symptoms.