Home-Based Transcutaneous Auricular Vagus Nerve Stimulation for Generalized Anxiety Disorder: Safety, Feasibility, and Preliminary Clinical Outcomes in a Single-Arm Prospective Study

Background: Generalized anxiety disorder (GAD) is associated with substantial psychological burden, autonomic dysregulation, and limitations of existing pharmacological and psychotherapeutic treatments. Transcutaneous auricular vagus nerve stimulation (taVNS) has emerged as a promising non-invasive neuromodulation approach, but evidence regarding home-based application in GAD remains limited. Objective: To evaluate the feasibility, safety, and preliminary clinical and physiological outcomes of a home-based taVNS intervention in adults with psychologist-confirmed moderate-to-severe GAD. Methods: In this prospective single-arm feasibility study, 48 participants initiated a 4-week home-based taVNS intervention consisting of two daily stimulation sessions performed five days per week. Clinical assessments were conducted at baseline, Week 2, Week 4, and follow-up visits at Weeks 6 and 8. Ambulatory electrocardiographic monitoring was performed before treatment initiation, at Week 2, and at the end of treatment to assess heart rate variability (HRV) using the root mean square of successive differences (RMSSD). Primary outcomes included feasibility, safety, adherence, and change in clinician-rated anxiety severity (HAM-A). Results: Thirty-four participants completed the study and were included in the primary analyses. HAM-A scores decreased significantly from baseline to Week 4 ([EMD] -6.9, 95% CI -10.4 to -3.4, p = 0.001), with partial maintenance during follow-up. Improvements were also observed in Beck Anxiety Inventory scores, whereas changes in GAD-7, perceived stress, depressive symptoms, and sleep quality were not statistically significant. RMSSD increased significantly from baseline to Week 4 (EMD 6.7 ms, 95% CI 2.1-11.3, p = 0.009). Greater increases in RMSSD were associated with larger reductions in HAM-A (R^2 = 0.18, p = 0.031) and BAI scores (R^2 = 0.21, p = 0.019). No serious adverse events occurred. Mean adherence was 79.8%, and 73.5% of participants completed at least 70% of prescribed stimulation sessions. Conclusions: Home-based taVNS was feasible and generally well tolerated in adults with moderate-to-severe GAD. Preliminary improvements in clinician-rated anxiety severity and autonomic physiological measures were observed; however, the single-arm design precludes causal inference. These findings support further evaluation of home-based taVNS in adequately powered randomized sham-controlled trials.