The Affection of Temporal Factors on Acupuncture for Insomnia after Stroke: A Systematic Review and Meta-Analysis

Objective The aim of this systematic review and meta-analysis was to analyze the affection of temporal factors on acupuncture for insomnia after stroke. Methods Eight databases were searched from inception through September 2019 without language restrictions. Randomized controlled trials (RCTs) were included if pure acupuncture was compared to Western medicine for the treatment of insomnia after stroke. Results Thirty-two studies involving a total of 2347 participants were included. Comparing to Western medicine, the subgroup analysis showed there was no statistical significance among 9-12 am, 3-6 pm, and 2 hours before sleep to start the acupuncture for post-stroke insomnia on improving the effective rate (P=0.66) or the sleep quality (P=0.95). The cumulative meta-analysis showed that with the amount of treatment increased, the confidence interval was narrowed and the accuracy of the effect value was improved gradually. Conclusions The results of this study showed that acupuncture therapy was performed 2 hours before sleep, the insomnia could be improved by calming the mind and inducing the Yang into the Yin based on the theory of midnight-midday ebb flow. The most commonly used needle retention time of 30 minutes was effective in clinical, and with the amount of stimulation increases, the therapeutic effect of acupuncture could be sustained and stable. Since the overall risk of bias was evaluated as unclear, application of these conclusions needs to be cautious.