High-definition transcranial direct current stimulation (HD-tDCS) in major depressive disorder with anxious distress—a study protocol for a double-blinded randomized sham-controlled trial

Abstract

Abstract Background Comorbid anxiety disorders and anxious distress are highly prevalent among individuals with major depressive disorder (MDD). The presence of the DSM-5 anxious distress specifier (ADS) has been associated with worse treatment outcomes and chronic disease course. Few studies have evaluated the therapeutic effects of High-definition transcranial direct current stimulation (HD-tDCS) on depressive and anxiety symptoms among MDD patients with ADS. The current randomized controlled trial aims to assess the efficacy of HD-tDCS as an augmentation therapy with antidepressants compared to sham-control in subjects of MDD with ADS. Methods MDD patients with ADS will be recruited and randomly assigned to the active HD-tDCS or sham HD-tDCS group. In both groups, patients will receive the active or sham intervention in addition to their pre-existing antidepressant therapy, for 2 weeks with 5 sessions per week, each lasting 30 min. The primary outcome measures will be the change of depressive symptoms, clinical response, and the remission rate as measured with the 17-item Hamilton Depression Rating Scale (HDRS-17) before and after the intervention and at the 2nd and 6th week after the completed intervention. Secondary outcome measures include anxiety symptoms, cognitive symptoms, disability assessment, and adverse effects. Discussion The HD-tDCS applied in this trial may have treatment effects on MDD with ADS and have minimal side effects. Trial registration The trial protocol is registered with www.chictr.org.cn under protocol registration number ChiCTR2300071726. Registered 23 May 2023.