Transcutaneous auricular vagus nerve stimulation in treatment of primary Parkinson's disease: a randomized, controlled, single-blind trial

To explore the therapeutic effect of transcutaneous auricular vagus nerve stimulation (taVNS) on autonomic and motor symptoms in primary Parkinson's disease (PD).

A total of 60 patients with primary PD were randomly divided into an observation group (30 cases, 1 case excluded and 1 case dropped out) and a control group (30 cases, 4 cases excluded and 1 case dropped out). The patients of the two groups received the oral administration of compound levodopa. If the patients had taken the other anti-PD drugs except compound levodopa preparations before enrolled, the original medication regimen was remained. The treatment lasted 8 weeks. In the observation group, the taVNS was delivered with SDZ-ⅡB type electric acupuncture instrument attached to the concha unilaterally and alternatively, at the frequency of 4 Hz/20 Hz and disperse-dense wave, and at the electric current of 5 mA to 10 mA, for 30 min each time. The taVNS was given 3 times a week, at least once every two days and for 8 weeks. In the control group, the pulse stimulation was given at the scapha, the operation and duration of treatment were the same as the observation group. The scores were observed for the scale for outcomes in Parkinson's disease-autonomic symptoms (SCOPA-AUT), part Ⅲ/Ⅱ of Movement Disorder Society-unified Parkinson's disease rating scale (MDS-UPDRS-Ⅲ, MDS-UPDRS-Ⅱ), the geriatric tremor syndrome in TCM, the modified Hoehn-Yahr (H-Y) rate, and Parkinson's disease quality of life questionnaire (PDQ-39) before and after treatment; and the safety of treatment was evaluated after treatment in the two groups.

After treatment, the scores of SCOPA-AUT, MDS-UPDRS-Ⅲ, MDS-UPDRS-Ⅱ, geriatric tremor syndrome of TCM and PDQ-39 were all lower than those before treatment in the observation group (P<0.001, P<0.05); PDQ-39 score was higher in the control group compared with that before treatment (P<0.05), and the other indexes did not show the statistical differences (P>0.05). There was no difference in H-Y rate after treatment between the two groups (P>0.05). In the observation group, the reduction ranges of SCOPA-AUT, MDS-UPDRS-Ⅱ, geriatric tremor syndrome of TCM and PDQ-39 scores were larger when compared with the control group (P<0.001). The obvious adverse reactions were not presented in the two groups.

The ta VNS, as an adjunctive therapy to medication with compound levodopa, can attenuate the autonomic and motor symptoms of the patients with primary PD and improve the daily quality of life without adverse reactions.