Randomized clinical trial on the efficacy of a new transcranial direct current stimulation (tDCS) device in the treatment of depression: a low-cost option for developing countries?

ABSTRACT Objective: Verify the clinical efficacy and safety of a low-cost tDCS device, in a clinical trial for major depressive disorder. Methods: 168 persons were recruited; 32 depressed individuals with moderate or severe depressive symptoms (HDRS17 scores higher than 18) were included and randomized for the trial (16 individuals in each group). The intervention consisted of 10 active anodal tDCS sessions at 2 mA for 30 minutes over the left dorsolateral prefrontal cortex; or sham. The main outcome was HDRS17; secondary outcomes included satisfaction (TSQM II) and quality of life (WHOQOL-BREF). Assessments at baseline, endpoint and at 30 days follow-up. Results: The sample was composed by a total of 11 men and 21 women, mean age of 42.75 years (95% CI: 38.10-47.40). Active treatment was superior than sham: There was a significant interaction between group and time regarding HDRS-17 scores (F = 4.089, df = 2, p = 0.029; partial Eta squared = 0. 239). Post hoc analyses exhibited a statistically significant difference between active and sham group symptoms after a 30 days follow-up (difference = -7.75, p = 0.008, Cohen’s d = 1.069). There were 3 dropouts, all in the active group, due schedule issues. No severe adverse effects reported. Conclusion: The current active tDCS protocol was related with clinical improvement of depressive symptoms. Intervention was well-tolerated. Non-invasive brain stimulation techniques are still not routinely used, although a viable strategy for treatment-resistant patients, partial responders and people unable to use pharmacological treatment. We aim to increase knowledge and use of tDCS for the Brazilian population.