Auricular Vagus Nerve Stimulation Combined with Physical Therapy for Individuals with Parkinsons Disease: A Pilot Randomized Sham-controlled Trial

Background and PurposeNeuromodulation and physical therapy (PT) can both mitigate motor and non-motor symptoms of Parkinsons Disease (PD). There are a lack of studies examining the integration of transcutaneous auricular vagus nerve stimulation (taVNS) with PT or exercise for improving Parkinsonian symptoms. The study was designed to investigate the safety, tolerability, and feasibility of combining bilateral taVNS with PT to enhance the therapeutic benefits of exercise as medicine in a clinical setting. MethodsThis pilot study was a randomized, sham-controlled clinical trial. Participants were randomly assigned to receive active or sham bilateral taVNS in combination with physical therapy for 12 visits over 6 weeks. We quantified safety, tolerability, and feasibility outcomes, and explored changes in cardiovascular and motor function over time. ResultsWe observed taVNS was well tolerated without reported adverse events. We observed taVNS administered prior to physical therapy significantly decreased heart rate and blood pressure at rest. We observed the active taVNS treatment group exhibited more sustained improvements in motor function and balance compared to baseline. Due to the small size of the feasibility study, we did not detect between-group differences. Discussion and ConclusionsCombining taVNS with physical therapy was safe, feasible, and well-tolerated. Preliminary results suggest taVNS has the potential to enhance rehabilitation outcomes by modulating cardiovascular function prior to and during PT and exercise. These findings support the need for larger clinical trials and real-world studies investigating the integration of taVNS into PT and exercise methods for improving PD symptomology. Trial RegistrationClinicalTrials.gov NCT05871151