Personalized High-Definition Transcranial Direct Current Stimulation (HD-tDCS) Treatment for Major Depressive Episode

Neuroimaging Biomarker-guided Personalized High-Definition Transcranial Direct Current Stimulation (HD-tDCS) Treatment for Major Depressive Episode in Adolescents With Mood Disorders: A Randomized Controlled Study

Adolescents with mood disorders experiencing major depressive episode have poor efficacy of medication treatment. High-Definition Transcranial Direct Current Stimulation (HD-tDCS) has been proven adjuvant efficacy in patients with major depressive episode. However, the optimal evidence-based stimulation parameters have not been clearly defined, which greatly limits the efficacy of HD-tDCS in the treatment of major depressive episode.This trial will compare a novel form of accurate and personalized HD-tDCS treatment protocol guided by neuroimaging biomarkers to the routine stimulation(stimulation target is L-DLPFC, central electrode is anode).The personalized selection of stimulation site, central electrode polarity will be determined by neuroimaging biomarkers. The study aims to propose a novel personalized neuroimaging-guided HD-tDCS strategy, to evaluate the efficacy and safety of the treatment, further to understand the biological mechanism of the personalized HD-tDCS treatment.

Mood disorders, including mainly bipolar disorder (BD) and major depressive disorder (MDD), have become the primary health problem and one of the leading causes of functional disability in adolescents . In China, the incidence of mood disorders such as BD and MDD in adolescence has increased rapidly in recent years. Particularly, patients with mood disorder currently experiencing major depressive episode have high risk of suicide, and pharmacological treatment showed poor efficacy to such depressive patients. Mood disorders with major depressive episode have become one of the major threats to the mental health of adolescents in China. Therefore, it is of great significance to explore a series of early intervention strategies for adolescents with major depressive episode. HD-tDCS is a non-invasive brain stimulation treatment strategy with mild side effects. The set of stimulation parameters often has a vital impact on the final clinical efficacy of HD-tDCS treatment. Several clinical trials have reported the efficacy and safety of HD-tDCS on treatment major depression disorder. However, the evidence-based optimal targets and other stimulation parameters have not been clearly defined, which greatly limits the efficacy of HD-tDCS in the treatment of major depressive episode. To date, there is no large randomized clinical trial (RCT) exploring an optimization of HD-tDCS on adolescents with major depressive episode. This study is a randomized controlled trial aiming at assessing the efficacy and safety of a novel personalized HD-tDCS treatment protocol compared to routine stimulation for major depressive episode in adolescents with mood disorders. Participants will be assigned randomly (1:1) to the personalized HD-tDCS group or the routine HD-tDCS group. Participants will be treated with 20 sessions (2 sessions per day) HD-tDCS treatment. The stimulation parameters of routine HD-tDCS group are: current=2 mA, duration=20 min, stimulation target=L-DLPFC, central electrode=anode. The stimulation parameters of personalized HD-tDCS group are current=2 mA and duration=20 min, while the stimulation target and central electrode polarity are based on neuroimaging biomarkers extracted via machine learning. Participants in both groups will maintain the stable drug regimen during the HD-tDCS trial.

Inclusion Criteria:

• Between 13 and 18 years of age;
• Participants fulfill the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) diagnostic criteria for major depressive disorder (MDD) or bipolar disorder (BD);
• Participants are assessed by the Schedule for Affective Disorders and Schizophrenia for School-Age Children-Present and Lifetime version (K-SADS-PL);
• A current moderate or severe depressive episode defined by HAMD>17;
• Participants receive a stable psychotropic medication regimen prior to randomization to the trial and patient will be willing to remain on the stable regimen during the HD-tDCS treatment phase;
• All participants provided written informed consent by themselves or their guardians after the detailed description of the study.

Exclusion Criteria:

• Prior rTMS, tDCS, electroconvulsive therapy (ECT) application or standard psychological therapy within 6 months prior to screening;
• Comorbidity of other DSM-IV axis I disorders or personality disorders;
• Judged clinically to be at serious suicidal risk;
• Diabetes mellitus, hypertension, vascular and infectious diseases and other major medical comorbidities;
• Unstable medical conditions, e.g., severe asthma;
• Neurological disorders, e.g., history of head injury with loss of consciousness for ≥ five minutes, cerebrovascular diseases, brain tumors and neurodegenerative diseases;
• Mental retardation or autism spectrum disorder;Contraindications to MRI (e.g., severe claustrophobia, pacemakers, metalimplants);
• Contraindications to HD-tDCS (e.g., scalp rupture, cranial plates, history of seizure,electroencephalogram (EEG) test suggesting high risk of seizure, known brain lesion);
• Current drug/alcohol abuse or dependence;Pregnant or lactating female.