Comparison of Two tDCS Protocols for the Treatment of Major Depressive Disorder

University of Sao Paulo

Status: Completed

Conditions: MAjor Depressive Disorder

Treatments: Device: Transcranial Direct Current Stimulation

Study type: Interventional

Funder types: Other

Identifiers

NCT01877447

aF3_cF4_F32

Details and patient eligibility

About

Transcranial direct cranial stimulation (tDCS) is a novel technique based on the application of a weak electrical current over the scalp through two electrodes - the anode, which facilitates neuronal depolarization, and the cathode, which leads to neuronal hyper-polarization. Recently, several open-label and sham-controlled clinical trials applied daily tDCS sessions for the treatment of major depressive disorder (MDD). Theoretically, tDCS displays depression improvement through anodal stimulation over the left dorsolateral prefrontal, inducing excitability-enhancing effects over this area, which is hypoactive during the acute depressive episode. The present study is aimed at comparing two different tDCS protocols: (1) active anodic stimulation over left dorsolateral prefrontal cortex with cathode placed over an extra cephalic area; (2) active cathode placed over the right dorsolateral prefrontal cortex with anode placed over an extra cephalic area.

Full description

The present research protocol will evaluate clinical effects of two different tDCS protocols: (1) active anodic stimulation over left dorsolateral prefrontal cortex with cathode placed over an extra cephalic area; (2) active cathode placed over the right dorsolateral prefrontal cortex with anode placed over an extra cephalic area. Patients will be clinically evaluated with the Diagnostic and Statistical Manual of Mental Disorders Fourth Edition (DSM-IV) criteria for depression. Symptoms intensity will be rated according to The Hamilton Depression Scale (HAMD -17 items) - main outcome. Patients with scores higher than 16 will be included. Patients with active neurological or severe disorders (such as cancer or auto-imune disorders) will be excluded. The present study is a double-blinded, controlled, randomized trial with 30 patients with depression. The intervention protocol consist in 15 consecutive daily tDCS sessions (skipping the weekend). After meeting eligibility criteria, patients will be randomized (computer generated list) to one of the two intervention groups. We will use a direct current of 2.0 milliamperes (mA) for 30 min. The 35 cm2-rubber electrodes will be wrapped in cotton material, which should be moistened with saline as to reduce impedance. Patients will be clinically assessed at baseline and at end of 6 weeks. Main outcome will be based on HAMD-17 items at a final endpoint of 6-weeks, with secondary outcomes assessing Beck Depression Inventory (21 items) at 6 weeks. Other evaluation scales include Beck Anxiety Inventory, Hamilton Anxiety Scale and Safety and cognitive assessment will be performed with The Montreal Cognitive Assessment, adverse effects scales and clinical evaluation with a trained physician.

Enrollment: 30 patients

Sex: All

Ages: 18 to 89 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• patients with age between 18-89 years, depression diagnosis according to Diagnostic and Statistical Manual of Mental Disorders Fourth Edition (DSM-iV); HAMD scores higher than 16; accordance to inform consent

Exclusion criteria

• active neurologic or severe disorder (such as cancer or auto-imune)
• pregnancy;
• need for hospitalization

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Double Blind

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30 participants in 2 patient groups

cathodal F4

Experimental group

Description:

Transcranial Direct Current Stimulation Cathodal tDCS over F4 (right dorsolateral prefrontal cortex) Anodal tDCS over the left deltoid (extra-cephalic) n=15

Treatment:

Device: Transcranial Direct Current Stimulation

Anodal F3

Experimental group

Description:

Transcranial Direct Current Stimulation' Anodal tDCS over F3 (right dorsolateral prefrontal cortex) Cathodal tDCS over the right deltoid (extra-cephalic) n=15

Treatment:

Device: Transcranial Direct Current Stimulation