Time-course of the tDCS antidepressant effect: An individual participant data meta-analysis

Stevan Nikolin; Adriano Moffa; Lais Razza; Donel Martin; Andre Brunoni; Ulrich Palm; Frank Padberg; Djamila Bennabi; Emmanuel Haffen; Daniel M Blumberger; Mohammad Ali Salehinejad; Colleen K Loo

doi:10.1016/j.pnpbp.2023.110752

Time-course of the tDCS antidepressant effect: An individual participant data meta-analysis

Prog Neuropsychopharmacol Biol Psychiatry. 2023 Jul 13:125:110752. doi: 10.1016/j.pnpbp.2023.110752. Epub 2023 Mar 16.

Authors

Affiliations

¹ School of Psychiatry, University of New South Wales, Sydney, Australia; Black Dog Institute, Sydney, Australia. Electronic address: stevan.nikolin@unsw.edu.aua.
² School of Psychiatry, University of New South Wales, Sydney, Australia.
³ Serviço Interdisciplinar de Neuromodulação (SIN), Instituto de Psiquiatria, Hospital das Clínicas HCFMUSP, Faculdade de Medicina, Universidade de São Paulo, SP, Brazil; Ghent Experimental Psychiatry (GHEP) Lab, Ghent, Belgium; Department of Experimental Clinical and Health Psychology, Ghent University, Ghent, Belgium.
⁴ School of Psychiatry, University of New South Wales, Sydney, Australia; Black Dog Institute, Sydney, Australia.
⁵ Laboratory of Neurosciences (LIM-27), Instituto Nacional de Biomarcadores em Neuropsiquiatria (INBioN), Department and Institute of Psychiatry, Faculdade de Medicina da Universidade de São Paulo, Brazil; Department of Internal Medicine, Faculdade de Medicina da Universidade de São Paulo & Hospital Universitário, Universidade de São Paulo, Brazil.
⁶ Department of Psychiatry and Psychotherapy, University Hospital LMU, Munich, Germany.
⁷ Department of Psychiatry and Psychotherapy, University Hospital LMU, Munich, Germany; Medical Park Chiemseeblick, Bernau-Felden, Germany.
⁸ Centre d'Investigation Clinique, CIC-INSERM-1431, Centre Hospitalier Universitaire de Besançon CHU, Besançon, France.
⁹ Temerty Centre for Therapeutic Brain Intervention and Campbell Family Research Institute, Centre for Addiction and Mental Health and Department of Psychiatry, University of Toronto, Ontario, Canada.
¹⁰ Department of Psychology and Neurosciences, Leibniz Research Centre for Working Environment and Human Factors, Dortmund, Germany.

PMID: 36931456
DOI: 10.1016/j.pnpbp.2023.110752

Abstract

Introduction: Prefrontal transcranial direct current stimulation (tDCS) shows promise as an effective treatment for depression. However, factors influencing treatment and the time-course of symptom improvements remain to be elucidated.

Methods: Individual participant data was collected from ten randomised controlled trials of tDCS in depression. Depressive symptom scores were converted to a common scale, and a linear mixed effects individual growth curve model was fit to the data using k-fold cross-validation to prevent overfitting.

Results: Data from 576 participants were analysed (tDCS: n = 311; sham: n = 265), of which 468 were unipolar and 108 had bipolar disorder. tDCS effect sizes reached a peak at approximately 6 weeks, and continued to diverge from sham up to 10 weeks. Significant predictors associated with worse response included higher baseline depression severity, treatment resistance, and those associated with better response included bipolar disorder and anxiety disorder.

Conclusions: Our findings suggest that longer treatment courses, lasting at least 6 weeks in duration, may be indicated. Further, our results show that tDCS is effective for depressive symptoms in bipolar disorder. Compared to unipolar depression, participants with bipolar disorder may require additional maintenance sessions to prevent rapid relapse.

Keywords: Depression; Individual participant data; Meta-analysis; Transcranial direct current stimulation; tDCS.

Publication types

Meta-Analysis
Review
Research Support, Non-U.S. Gov't

MeSH terms

Antidepressive Agents / therapeutic use
Bipolar Disorder* / therapy
Depressive Disorder, Major* / therapy
Double-Blind Method
Humans
Transcranial Direct Current Stimulation* / methods
Treatment Outcome

Substances

Antidepressive Agents