Efficacy of neurostimulation across mental disorders: systematic review and meta-analysis of 208 randomized controlled trials
Hyde et al, 2022. Molecular Psychiatry.
A systematic review and meta-analysis of 208 randomized sham-controlled trials using TMS and/or tDCS to treat children and/or adults with a primary diagnosis of a mental health condition using standardized diagnostic criteria.
The majority investigated patients with major depressive disorder (MDD) or bipolar disorder (n = 99), and schizophrenia or schizoaffective disorder (n = 59), followed by obsessivecompulsive disorder (OCD, n = 27), substance use disorder (SUD, n = 10), posttraumatic stress disorder (PTSD, n = 8), generalized anxiety disorder (GAD, n = 5), attention deficit/hyperactivity disorder (ADHD, n = 2), and tourettes/tic disorders (n = 2).
Change in core symptom severity in each mental disorder was the primary outcome. Secondary outcomes were score changes in standard cognitive functioning tasks.
Regarding tDCS, active stimulation was significantly better than sham for symptoms of depression, SUD (substance use disorder), total, negative symptoms and auditory hallucinations in schizophrenia; but not for symptoms of GAD (generalized anxiety disorder), OCD (obsessive-compulsive disorder), and overall positive symptoms in schizophrenia.
Notably, effect sizes for tDCS overall depression symptom improvement were higher than those reported in previous studies, and are comparable to those recently reported for psycho- and pharmacotherapies.