Beyond the Surface: Deep TMS Efficacy in Reducing Craving in Addictive Disorders. A Systematic Review and Meta-analysis.

Background: Substance use disorders (SUDs) and Gambling Disorder (GD) are addictive diseases with a chronic course. Due to the limited efficacy of conventional treatments, there is growing interest in alternative approaches targeting the altered neural circuits underlying these disorders. Deep Transcranial Magnetic Stimulation (dTMS) has emerged as a promising neuromodulation technique capable of reaching deep and bilateral brain regions. However, no definite recommendation for its use in addiction treatment exists. This study systematically reviewed and quantitatively analyzed dTMS effects in SUDs and GD.

Methods: Following the PRISMA guidelines, we screened four electronic databases up to February 2024 and selected relevant English-written original research articles. Seventeen papers were included in the systematic review. As only a minority of studies employed a sham-controlled design, we ran the meta-analysis on a subset of 12 studies, computing the pre-post real stimulation standardized mean change (SMCC) as the effect size, using self-reported craving scores as the dependent variable.

Results: The results showed a significant and large effect of real dTMS in reducing craving scores (SMCC = - 1.26, 95% CI [-1.67, - 0.86], p <.001). High heterogeneity across studies was found at both quantitative and qualitative levels.

Conclusions: Results provide preliminary evidence supporting the effectiveness of dTMS for SUDs treatment. Current limitations and future directions are critically discussed, highlighting the need for further rigorous research to refine the therapeutic potential and develop consensus-based guidelines for dTMS clinical application.