Clinical Trial ARTICLE
Multiple sessions of transcranial direct current stimulation (tDCS) reduced craving and relapses for alcohol use: A randomized placebo-controlled trial in alcohol use disorder
- 1Health Sciences Center, Federal University of Espírito Santo, Brazil
- 2Dept. Psychology and Neurosciences, Leibniz Research Centre for Working Environment and Human Factors, Germany
- 3Department of Neurology, Berufsgenossenschaftliches Universitätsklinikum, Germany
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 x 7 cm2, 2 mA, for 20 minutes, 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 five 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 three-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.
Keywords: alcohol dependence, tDCS, dorsolateral prefrontal cortex, craving, relapses.
Received: 20 May 2018;
Accepted: 13 Jun 2018.
Edited by:Francisco Lopez-Munoz, Universidad Camilo José Cela, Spain
Reviewed by:Gabriel Rubio, Hospital Universitario 12 De Octubre, Spain
Thomas E. Gladwin, University of Chichester, United Kingdom
Copyright: © 2018 Klauss, Anders, Felippe, Nitsche and Nakamura-Palacios. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence: Dr. Ester M. Nakamura-Palacios, MD, PHD., Federal University of Espírito Santo, Health Sciences Center, Vitória, Brazil, firstname.lastname@example.org