Home-based transcranial direct current stimulation for major depressive disorder: 6-month follow-up from a randomised sham-controlled trial

Transcranial direct current stimulation (tDCS) is a potential home-based treatment for major depressive disorder (MDD). In our randomised controlled trial, a fully remote, 10-week course of home-based active tDCS showed greater clinical efficacy as compared to sham tDCS in a double-blind randomised controlled trial (RCT). tDCS was administered at 2mA for 30-minute sessions in a bifrontal montage with anode over the left dorsolateral prefrontal cortex (DLPFC) and cathode over the right DLPFC. Following the 10-week blinded trial, all participants could receive active tDCS in a 10-week open label phase. Participants who had completed the open-label treatment were invited for additional long term follow-up visits over 6 months. Participants were allowed to keep their tDCS device and could choose to continue stimulation during the follow-up period. In the follow-up phase, 42 participants (27 women) attended at least one visit. Ongoing use of the tDCS device was 59% at 3 months and 55% at 6 months during the follow-up period. The clinical response rate was 64% at 3 months and 76% at 6 months. Participants who had shown a clinical response after open label treatment maintained a response rate of 90% at 6 months. In summary, high rates of clinical response were maintained in 6-month follow-up whether or not participants continued to use the tDCS device.