Transcranial direct current stimulation (tDCS) as an additional treatment to cognitive behavior group therapy in...

Transcranial direct current stimulation (tDCS) targeting the dorsolateral prefrontal cortex (DLPFC) has been proposed as a safe, accessible intervention for tobacco dependence. However, existing evidence is mixed and primarily limited to short-term outcomes. This study investigated the efficacy and safety of prefrontal tDCS as an adjunct to standardized cognitive behavioral group therapy (CBT) for tobacco dependence. In this double-blind, randomized, sham-controlled pilot trial conducted in Germany, adults with tobacco dependence defined by an Fagerström Test of Nicotine Dependence score >4 and CO levels >10 ppm were randomized to receive either active or sham tDCS alongside standardized group CBT. Participants underwent seven tDCS sessions followed by CBT over seven weeks. Active stimulation was delivered at 2 mA for 30 minutes over the left DLPFC (anode) and right supraorbital region (cathode). The primary outcome was abstinence at 6-month follow-up, analyzed in the modified intention-to-treat population. Of 190 individuals assessed for eligibility between July 2012 and November 2013, 54 were randomized (27 active, 27 sham), and 49 were included in the final analysis (23 male, 26 female; mean age 50.7 years, SD 12.3). At 6 months, the probability of abstinence was significantly higher in the active tDCS group (OR = 1.66, 95% CI = 1.02 to 2.70), with 50% abstinent vs. 26% in the sham group. No serious adverse events were reported. This pilot trial provides initial evidence supporting the safety and efficacy of combining prefrontal tDCS with group CBT for smoking cessation. Further research should explore mechanisms and long-term outcomes. Trial Registration: clinicaltrials.gov Identifier: NCT01729507.