Clinical trials of traditional Chinese medicine for insomnia: current status and future directions

Abstract

Insomnia is a prevalent condition. Traditional Chinese medicine(TCM), including Chinese herbal medicine, acupuncture, acupressure, and auricular therapy, have been used for treating insomnia for a long time. Over the past decade, a number of randomized controlled trials have been performed to examine the efficacy of various TCM treatments for insomnia. Several systematic reviews published to summarize the evidence of these treatments. In this selective review, we presented the most important findings of the recent studies and highlighted the future directions of research in the area. Over 10 systematic reviews on the efficacy and safety of TCM treatments for insomnia were examined. The most commonly used Chinese herbal formula for insomnia was Gui Pi Tang, followed by Xue Fu Zhu Yu Tang and Dan Zhi Xiao Yao San; while Suanzaoren(Ziziphusjujuba), Yejiaoteng(Polygonum multiflorum), and Fuling(Poria cocos) were the most frequently used single herb. The most selected acupoints included Shenmen(HT7), Yintang(EX-HN3), Sanyinjiao(SP6), Baihui(GV20), Anmian(EX-HN22), and Sishencong(EX-HN1). Although Chinese herbal medicine, acupuncture, acupressure, and auricular therapy have been reported to be more effective than placebo control, benzodiazepines, and other therapies in the acute treatment of insomnia, Most trials were rated as low quality trials as there was: ①no clear description of randomization method; ②no blinding on either the subjects or the assessors; and ③unclear report on the dropouts. These limitations may lead to biased results. Hence, the seemingly promising results should be interpreted with caution. Future studies should be improved with methodological rigorousness, such as precise diagnostic criteria, placebo-controlled and double-blind design, validated subjective scales, objective measures, and standardized adverse event monitoring are most warranted in order to accurately determine the benefits and risks of TCM treatments for insomnia. Studies comparing pattern-based individualized TCM treatments with standardized TCM treatments also helpto indicate the clinical values of TCM for insomnia. 失眠是一种常见精神疾病。多种中医疗法,包括中药、针灸、穴位按摩及耳穴疗法等,已长时用于治疗失眠。在过去十年,已有许多随机对照试验检验这些中医疗法治疗失眠的疗效,亦有一些荟萃分析系统评价中医疗法治疗失眠的临床疗效。在这篇综述中,我们回顾近期有关中医疗法治疗失眠的疗效和安全性以及对未来研究的建议相关文章。目前已经有超过10篇的系统评价总结中医治疗失眠的疗效。最常用的治疗失眠的方剂是归脾汤、血府逐瘀汤和丹栀逍遥散。最常用的单味中药有酸枣仁、夜交藤和茯苓。失眠最常用穴位有神门、印堂、三阴交、百会、安眠和四神聪。总而言之,虽然有研究指中药、针灸、穴位推拿和耳穴疗法比安慰剂对照、苯二氮?类药物或其他疗法更有效治疗失眠,但综观这些随机对照试验,方法学质量较低,因此这些看似正面的结果需要小心解读。大部份的随机对照试验被评为低质量原因为:①未清楚报告随机方法;②未使用盲法(不论是对病者或对评估者);③未清楚报告退出人数及原因。这些问题均可导致偏倚结果。将来的随机对照试验需更严谨的设计,如采用精确的诊断标准、安慰剂对照、双盲设计,用客观的量表评估睡眠,标准化的不良反应报告记录以及客观评价中医治疗失眠的优势和风险。