Home-based transcutaneous auricular vagus nerve stimulation (taVNS) improves motor and non-motor symptoms by improving autonomic and brain functions in patients with Parkinson's disease: A randomized clinical trial

Home-based transcutaneous auricular vagus nerve stimulation (taVNS) holds therapeutic potential for neurological disorders, yet its application in Parkinson's disease (PD) remains underexplored. In this single-blinded, placebo-controlled randomized clinical trial, PD patients received either home-based taVNS with specific stimulation parameters or sham stimulation for three weeks. TaVNS significantly improved motor symptoms, reflected as reduced MDS-UPDRS Ⅲ scores, and alleviated non-motor symptoms including quality of life and sleep disturbances compared with sham stimulation. Neuroimaging revealed that taVNS decreased glutamate levels in the striatum and thalamus, increased Regional Homogeneity values in the rolandic operculum, and enhanced fractional anisotropy in the left hippocampal cingulum and right inferior longitudinal fasciculus. Serum acetylcholine levels were elevated following taVNS and correlated with motor improvement. No serious adverse events occurred. These findings suggest that taVNS with specific parameters effectively alleviates motor and non-motor symptoms in PD, possibly through modulation of brain networks and vagal activity. TRIAL REGISTRATION: Chinese Clinical Trial Registry: ChiCTR230007082.