Transcranial direct current stimulation (tDCS) is a neuromodulation method that modulates brain activity using low-intensity electrical current. Used in the treatment of depression, it is easily adaptable for both caregivers and patients, with good tolerance, under appropriate supervision.

Allowing patients to perform tDCS at home could address issues of access to care (distance from home, overall cost of care, lack of healthcare professionals, difficulty travelling for physical/psychological reasons, etc.). Studies on tDCS have highlighted the importance of regular clinical monitoring to ensure compliance and safety, which are essential factors for therapeutic efficacy.

The main objective of this study is to demonstrate the non-inferiority of tDCS performed at home versus in hospital in terms of effectiveness in reducing depressive symptoms at 6 weeks post-treatment in patients with moderate to severe depression.

Inclusion Criteria:

• Men or women over the age of 18

• Psychiatric diagnosis:

  • Presenting a depressive episode characterised according to DSM-5 criteria
  • MADRS score greater than or equal to 20, indicating moderate to severe depression
  • Indication and prescription of a course of tDCS treatment consisting of 20 sessions of 30 minutes at 2mA, at a rate of 2 sessions per day

• Drug treatment:

  o Failure of a maximum of 1 or 2 antidepressants taken successively or in combination for the current episode

• Psychiatric follow-up: Receiving medical follow-up by a psychiatrist or referring physician

• Ability to understand and cooperate:

  • Having a smartphone, computer or tablet (with internet connection and Bluetooth) to use the digital interface required to perform remote tDCS
  • Be deemed capable of understanding the nature of the study and participating in clinical follow-up

• Informed consent: Have given written consent to participate in the research, after receiving oral and written information about the study.

• Social affiliation: Be affiliated with a social security system

Exclusion Criteria:

• Psychiatric or neurological diagnoses:

  • Chronic psychotic disorders or history of schizophrenia
  • Progressive neurological disorders (unstabilised epilepsy, brain tumour, recent stroke, severe head injury)

• History or current treatment of neuromodulation

  • Any history of tDCS treatment, whether carried out in a clinical or research setting
  • Current treatment or history of rTMS and ECT sessions for the current episode
  • Presence of an active vagus nerve stimulation implant

• Presence of a high risk of suicide. A risk of suicide will be considered high if the score on item 10 of the MADRS scale ("Suicidal Thoughts") is 4 or higher, and/or if there is active suicidal ideation accompanied by clinically identified intent or a plan

• Addiction and substance use: Current substance use disorder other than nicotine or caffeine

• Psychiatric comorbidities that may interfere with study participation, including: understanding information, adherence to the protocol, and completing CBT sessions.

• Recent change in curative psychotropic treatment (antidepressant, mood stabiliser including lithium and anticonvulsants, mood-stabilising antipsychotic) in the month prior to inclusion.

• Medical contraindication to stimulation:

  • Presence of a metallic or electronic implant in the skull or chest (pacemaker, neurostimulator, cochlear implant)
  • Skin lesion, irritation or wound on the electrode contact areas
  • History of epileptic seizures not related to an identified cause or not stabilised for more than 12 months
  • Current pregnancy or breastfeeding
  • Women of childbearing age without effective contraception (hormonal or medical device)

• A severe and/or progressive somatic condition requiring ongoing medical care that would interfere with participation in the study.

• Limited ability to participate:

  • A significant cognitive impairment or sensory deficit that prevents understanding of instructions

  • Inability to safely perform tDCS at home, as defined by at least one of the following:

    • inability to understand or recall essential instructions regarding procedure and safety;
    • inability to perform, following initial guidance, the essential steps for setting up and starting the device;
    • lack of the minimum material conditions required at home to conduct the sessions.

• Special legal or social situation:

  • Patients under guardianship, curatorship or judicial protection
  • Privation of liberty by judicial or administrative decision, Presence of a functional limitation to the independent performance of tDCS