Korean J Biol Psychiatry.  2025 Apr;32(1):9-16. 10.22857/kjbp.2025.32.1.002.

A Preliminary Study on the Effects of Transcutaneous Auricular Vagus Nerve Stimulation on Smoking Cessation and Related Psychological Factors

• Lee H
• Ryu S
• Kim WP
• Ryu H
• Kim EY

• KMID: 2567934
• DOI: http://doi.org/10.22857/kjbp.2025.32.1.002

Abstract

Objectives
Smoking causes 8 million deaths annually and significant socioeconomic burdens. Despite several therapies, cessation rates remain low due to nicotine’s addictive properties and withdrawal symptoms. This study evaluates the efficacy of transcutaneous auricular vagus nerve stimulation (taVNS) in reducing nicotine dependence and improving psychological states.
Methods
This pilot study enrolled 23 adult smokers aged 19 to 65 years with the Fagerström Test for Nicotine Dependence (FTND) scores over 4 and daily cigarette consumption exceeding 10. Participants were randomized into treatment and control groups. The treatment group received personalized taVNS stimulation targeting the auricular branch of the vagus nerve, applied for 30 minutes, three times daily, for four weeks. The control group received a low-level fixed-current stimulation. Outcomes, including the FTND, cigarettes per day (CPD), the Patient Health Questionnaire-9 (PHQ-9), the Generalized Anxiety Disorder-7 (GAD-7), and the Insomnia Severity Index (ISI), were assessed at baseline, 2 weeks, and 4 weeks. Statistical analyses included the Mann–Whitney U-test and Wilcoxon signed-rank test.
Results
The treatment group showed significant reductions in the FTND (2.0 points at 2 weeks, p<0.05; 3.0 points at 4 weeks, p<0.05) and CPD (1.0 fewer cigarette at 2 weeks, p<0.05; 2.0 fewer cigarettes at 4 weeks, p<0.05). Additionally, the PHQ-9 scores decreased significantly in the treatment group (3.0 points at 2 weeks, p<0.05; no further improvement at 4 weeks). However, the GAD-7 and the ISI scores showed no statistically significant changes in either group. The control group exhibited slight improvements in the FTND and the CPD, possibly due to placebo effects or motivation induced by study participation.
Conclusions
This study highlights taVNS as a promising non-invasive treatment for smoking cessation, effective in reducing nicotine dependence and improving depressive symptoms. However, its effects on anxiety and sleep quality remain unclear. Larger studies are needed to confirm its efficacy and explore optimal parameters and underlying mechanisms.

Keyword

Vagus nerve stimulation; Smoking cessation; Nicotine; Depression; Anxiety