[Systematic review and Meta-analysis on the auriculotherapy in treatment of insomnia].

Objective: To review the effectiveness and safety of auriculotherapy in treatment of insomnia.

Methods: The articles were collated by computer retrieval from 8 databases from the initiation to April 30, 2021, i.e. PubMed, EMbase, the Cochrane Library, the Web of Science, CNKI, Wanfang database, VIP and Chinese biomedical literature database (SinoMed). Meta-analysis was conducted with RevMan5.3 software.

Results: A total of 38 articles were included, with 3 707 cases involved. The results showed: ①The effective rate of auriculotherapy was better than that of single application of western medication with sleeping pills (=1.26, 95%:1.15 to 1.39, =4.77, <0.000 01), conventional acupuncture (=1.10, 95%: 1.05 to 1.16, =3.83, =0.000 1) and Chinese herbal medicine (=1.41, 95% 1.23 to 1.63, 4.80, <0.000 01), respectively. ② The total score of PSQI was reduced remarkably under the auriculotherapy when compared with the single application of western medication (-1.61, 95%: -2.61 to -0.60, =3.14, 0.002) and Chinese herbal medicine (-3.76, 95%: -4.84 to -2.68, =6.84, <0.000 01). But the difference was not significant when compared with conventional acupuncture (=-1.02, 95%: -2.11 to 0.08, =1.82, =0.07). ③Auricular point selection: the auricular points distributed in the areas of vagus nerve were more advantageous in reducing PSQI score (=-3.21, 95%: -4.45 to -1.96, =5.03, <0.000 01) compared with the points in other areas. ④Stimulant selection: the difference in the effective rate was not significant among different stimulants (magnetic beads, the seeds of , micro-needles) (=1.62, 95%: 0.71 to 3.73, =1.14, =0.25). ⑤Stimulation frequency: there was no significant difference between high-frequency stimulation and low-frequency stimulation of auricular point sticking in improving the effective rate and reducing PSQI score (>0.05). But the result should be considered cautiously in terms of the sensitivity analysis. ⑥Adverse reactions: the case numbers of adverse reactions of auriculotherapy (auricular point sticking) were less than those of western medication (=0.15, 95%: 0.06 to 0.35, =4.38, <0.000 1).

Conclusion: Auriculotherapy has certain curative advantages in treatment of insomnia compared with western and Chinese medications as well as conventional acupuncture. This therapy may relieve the symptoms of insomnia and has less adverse effects. But those outcomes need to be further verified with more high-quality randomized controlled trials.