Despite the system of care in place, patients suffering from an alcohol use disorder (AUD) continue to relapse after their detoxification. For about twenty years, neuromodulations and their mechanisms have been investigated in research in order to apply it as a therapeutic means, in particular direct current transcranial stimulation (tDCS). A previous study found a reduction of relapse rate thanks to the tDCS over the dorsolateral prefrontal cortex (DLPFC; anode on the right and cathode on the left) combined with an ICT.

This clinical trial of 5 sessions of tDCS alone on the DLPFC (20 minutes, anode on the right, cathode on the left). This study follows the same tDCS configuration as the previous one and takes place in the same multidisciplinary detoxification framework in order to see the relevance of using combined tDCS or only tDCS in clinical practice.

Hypotheses: For patients with AUD five sessions of tDCS during a detoxification:

• decrease the relapse rate 2 weeks after the treatment;
• decrease patient craving;
• decrease depression and anxiety symptoms;
• strengthen working memory performances.

Context: This is a clinical trial that is part of an alcohol detoxification cure at Unit 72 Addictology of CHU Brugmann. The idea is to add a neuromodulation intervention to the initial management, multidisciplinary and psycho-bio-social. This will be a randomized, sham-controlled, single-blind study.

A total of 60 subjects will be recruited according to the inclusion and exclusion criteria. They will be randomly divided into two groups: the 'active' group (A) that will benefit from tDCS stimulation and the 'sham' group (S).

Measures:

Primary dependent variables :

Relapse and total abstinence measured at several defined times: two weeks, one month, three months, six months and one year after treatment.

Secondary dependent variables:

• Craving measured before and after each tDCS session via visual analog scales, such as Likert 0 to 10. Craving will also be measured in T1 and T2 through the Craving Experience Questionnaire (CEQ);
• Symptoms of depression with the Beck Depression Inventory (BDI-II) and positive and negative affectivity with the Positive and Negative Affect Schedule (PANAS) measured at T1 and T2;
• Anxiety trait in T1 and T2 with the State Anxiety Inventory (STAI-A).
• The working memory performance measured in T1 and T2 with the span reversed.

All the questionnaires were in French version.

Metacognition items: At the end of the experiment, patients will be asked orally (1) Do you think you are in the active tDCS group?, (2) Would you be interested in continuing this intervention over a longer period of time?

Statistical analyses:

Primary measurement: In order to respond to our primary assumptions about relapse, a logistic regressions will be performed with the independent variable conditions (tDCS active scored 1 and tDCS sham scored -1) and the variable dependent relapse at each measurement (2 weeks, 1 month, 3 months, 6 months and 1 year). A Kaplan-Meier survival analysis will be performed on the number of days prior to relapse to compare the curves up to one year of follow-up.

Secondary measures: In order to respond to our secondary assumptions about the variables before and after the intervention, mixed repeated measures ANOVAs [Time (T1 vs. T2) x Condition (tDCS active vs. tDCS sham)] will be performed.

Inclusion Criteria:

• French speaker
• Severe Alcohol Use Disorder requiring alcohol rehabilitation
• Desire to stay sober for at least the next six months

Exclusion Criteria:

• Neurological history (epilepsy, head injury, and stroke)
• Mental confusion or severe cognitive impairment
• Schizophrenia, chronic psychotic disorders or bipolar type 1 disorder
• Metal in the brain
• Pregnancy
• Having participated in our previous study combining tDCS with ICT

sham tDCS protocol: 0 mA but 30s of 2 mA at the start and the end of the session