[Transcutaneous vagus nerve stimulation for primary insomnia and affective disorder:a report of 35 cases]

To observe and evaluate the clinical efficacy of transcutaneous vagus nerve stimulation (taVNS) at auricular concha for primary insomnia (PI) and affective disorder.

A total of 35 patients who met the diagnosis standard of PI in Diagnostic and statistical manual of mental disorders (5th edition) were included. The self-developed auricular vagus nerve stimulator (TENS-200A) was applied at auricular concha, 30 min per treatment, twice a day, 5 days a week for consecutive 4 weeks. The follow-up visit was conducted at the end of 6th week. The Pittsburg sleep quality index scale (PSQI), 17-items Hamilton depression scale (17HAMD) and Hamilton anxiety scale (HAMA) were applied for evaluation. The PSQI, HAMA and 17HAMD were observed before and after treatment; the safety was also observed.

Compared before treatment, the PSQI was significantly decreased to (13.20±3.61) at the end of 2nd week (P<0.05); compared before treatment, the 17HAMD and HAMA were significantly decreased at the end of 4th week and 6th week (all P<0.05). No adverse reaction was observed.

The taVNS could not only relieve PI symptoms, but also improve the depressive and anxiety symptoms, in addition, it may have positive long-term efficacy and safety.