Multiple Sessions of Transcranial Direct Current Stimulation (tDCS) Reduced Craving and Relapses for Alcohol Use: A Randomized Placebo-Controlled Trial in Alcohol Use Disorder.

Jaisa Klauss,Michael A Nitsche,Quézia S Anders,Luna V Felippe,Ester M Nakamura-Palacios

doi:10.3389/fphar.2018.00716

Abstract

Background: Transcranial direct current stimulation (tDCS), a non-invasive brain stimulation technique, has been studied as an adjunctive therapeutic agent for alcohol dependence. In a previous study, we showed that five consecutive sessions of tDCS applied bilaterally over the dorsolateral prefrontal cortex (dlPFC) reduced relapse to the use of alcohol in alcohol use disorder (AUD) outpatients. However, no changes on craving scores were observed. In the present study, we investigated if an extended number of sessions of the same intervention would reduce craving and relapses for alcohol use in AUD inpatients.Methods: Thus, a randomized, double-blind, sham-controlled, clinical trial with parallel arms was conducted (https://clinicaltrials.gov/ct2/show/NCT02091284). AUD patients from two private and one public clinics for treatment of drug dependence were randomly allocated to two groups: real tDCS (5 × 7 cm2, 2 mA, for 20 min, cathodal over the left dlPFC, and anodal over the right dlPFC) and sham-tDCS. Real or sham-tDCS was applied once a day, every other day, in a total of 10 sessions. Craving was monitored by a 5-item obsessive compulsive drinking scale once a week (one time before, three times during and once after brain stimulation) over about 5 weeks.Results: Craving scores progressively decreased over five measurements in both groups but were significantly reduced only in the real tDCS group after treatment. Corrected Hedges' within-group (initial and final) effect sizes of craving scores were of 0.3 for the sham-tDCS and of 1.1 for the real tDCS group. Effect size was 3-fold larger in the real tDCS group. In addition, the between-group analysis on craving score difference was nearly significant, and the effect size was 0.58, in favor for a larger effect in the real tDCS group when compared to sham-tDCS. Furthermore, in a 3-months follow-up after intervention, 72.2% of sham-tDCS group relapsed to the alcohol use whereas 72.7% of tDCS group were abstinent.Conclusions: Multiple sessions of bilateral prefrontal tDCS were well tolerated with no significant adverse events. Thus, extended repetitive bilateral tDCS over the dlPFC is a promising adjunctive clinical tool that could be used to reduce alcohol craving and relapses and facilitate alcoholism cessation.

Highlights

Alcohol is a highly addictive substance and alcohol dependence is a chronically relapsing disorder
They started to use alcohol on average at 16.2 years of age, consumed on average 17.9 drinks per day, and they were about 33 days abstinent before the beginning of the experimental protocol (Table 2). None of these characteristics differed between sham and real Transcranial direct current stimulation (tDCS) groups (Table 2)
Except for the marital state, alcohol use disorder (AUD) patients from sham- and real-tDCS groups were matched by socio-demographic characteristics such as age, gender, schooling and employment conditions and by characteristics of alcohol use, especially the age at the onset of alcohol use and days of abstinence before tDCS

Summary

Introduction

Alcohol is a highly addictive substance and alcohol dependence is a chronically relapsing disorder. It induces tolerance such that increased doses of the alcohol are required to achieve the desired effects and is associated with adverse symptoms during its acute withdrawal. Craving can be caused by an alteration of the relevant brain circuitry, that may persist even when the individual is not currently using the substance, but is exposed to stimuli that are associated with it (Volkow et al, 2011; DSM-5, 2013; Koob and Volkow, 2016), constituting a recognized central driving force for successive relapses and perpetuation of drug use (Self, 1998; Weiss, 2005). We investigated if an extended number of sessions of the same intervention would reduce craving and relapses for alcohol use in AUD inpatients

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Conclusion