Objectives: To review trials on the efficacy and safety of auricular acupuncture (AA) treatment for insomnia and to identify the most commonly used auricular acupoints for treating insomnia in the studies via a frequency analysis.
Data sources: The international electronic databases searched included: (1) AMED; (2) the Cochrane library; (3) CINAHL; (4) EMBASE; and (5) MEDLINE. Chinese electronic databases searched included: (1) VIP Information; (2) CBMdisc; and (3) CNKI.
Study selection: Any randomized controlled trials using AA as an intervention without using any co-interventions for insomnia were included. Studies using AA versus no treatment, placebo, sham AA, or Western medicine were included.
Data extraction: Two (2) independent reviewers were responsible for data extraction and assessment. The efficacy of AA was estimated by the relative risk (RR) using a meta-analysis.
Results: Eight hundred and seventy eight (878) papers were searched. Six (6) trials (402 treated with AA among 673 participants) that met the inclusion criteria were retrieved. A meta-analysis showed that AA was chosen with a higher priority among the treatment subjects than among the controls (p < 0.05). The recovery and improvement rates produced by AA was significantly higher than those of diazepam (p < 0.05). The rate of success was higher when AA was used for enhancement of sleeping hours up to 6 hours in treatment subjects (p < 0.05). The efficacy of using Semen vaccariae ear seeds was better than that of the controls (p < 0.01); while magnetic pearls did not show statistical significance (p = 0.28). Six (6) commonly used auricular acupoints were Shenmen (100%), Heart (83.33%), Occiput (66.67%), Subcortex (50%), Brain and Kidney (each 33.33%, respectively).
Conclusions: AA appears to be effective for treating insomnia. Because the trials were low quality, further clinical trials with higher design quality, longer duration of treatment, and longer follow-up should be conducted.