To explore the efficacy, adverse reactions, and feasibility of high-definition transcranial direct current stimulation(HD-tDCS) treating major depressive disorder(MDD) patients with anxious distress.

Sixty cases of MDD with anxious distress admitted to Zhenjiang Mental Health Center were recruited as participants. All patients were allocated into either the active treatment group or the sham group based on the random number table method. HD-tDCS was utilized in both groups to stimulate the left dorsolateral prefrontal cortex on the basis of conventional antidepressant treatment. In the active group, 2mA current stimulation was used for 20 min, and in the sham group, a 30-sceond stimulation was adopted at the beginning and the end of the stimulation. Participants in both group were treated once a day, five times a week for two consecutive weeks. Anxiety and depression symptoms of the patients were assessed respectively by the Hamilton depression scale(HAMD₁₇), the Montgomery-Asberg Depression Rating Scale(MARDS), the Hamilton Anxiety Scale(HAMA), and the Beck Anxiety Inventory(BAI) at the baseline, 2nd, 4th, and the 6th weekend of the treatment. The differences between active treatment and sham groups were analyzed by repetitive measure analysis of variance and simple effect analysis. Fisher′s exact probability test was used to compare the effective rate, remission rate and adverse reaction rate between the two groups.

(1) The interaction of times and groups was significant in HAMD₁₇(F=3.29,P<0.05) and BAI(F=2.99, P<0.05). In all measurement instruments, the main effects of groups(F=4.40-7.94) and times(F=35.42-247.59) were significant(P<0.05).(2) Findings from the simple effect analysis showed that: there were no significant differences in the scores of HAMD₁₇ at baseline and the 2^nd assessment between the two groups. Similarly, no significant differences were found in BAI at baseline, the 2nd and the 6th weekend of the treatment between two groups(P>0.05).(3) The scores of HAMD₁₇ at the 4th and the 6th week, BAI at the 4th weekend of the treatment in the active group were significantly lower than that in the sham group(P<0.05).(4) At the 4th weekend of the treatment, the active group had a remission rate of 16/20 and a response rates of 19/20, which were higher than 9/19 and 13/19, respectively, in the sham group(P<0.05). Also, the remission rate(18/20) in the active group was higher than that in the sham group(11/19) at the 6th weekend of the treatment.(P<0.05). As for the response rates, differences were not found between the two groups at the 6th weekend of the treatment.(5) The overall dropout rate had no significant differences in-between(P>0.05). As for the safety outcome, the rate of adverse events(e.g., itching, tingling and headache) showed no significant differences between the two groups. Additionally, no severe adverse events or mania was reported.

This study indicated that HD-tDCS has significant efficacy and high safety in the treatment among MDD patient with anxious distress. Nevertheless, further large sample clinical studies are warranted to confirm the findings of the current investigation.

Depressive disorder; Anxiety; High-definition transcranial direct current stimulation; Major depressive disorder with anxious distress; Efficacy; Adverse event