Chinese Herbal Medicines for the Treatment of Type A H1N1 Influenza: A Systematic Review of Randomized Controlled Trials

BackgroundChinese herbs are thought to be effective for type A H1N1 influenza. Series of Chinese herbs have been authorized recommended by the Chinese government, and until now a number of clinical trials of Chinese herbs for H1N1 influenza have been conducted. However, there is no critically appraised evidence such as systematic reviews or meta-analyses on potential benefits and harms of medicinal herbs for H1N1 influenza to justify their clinical use and their recommendation.
Methods and FindingsCENTRAL, MEDLINE, EMBASE, CBM, CNKI, VIP, China Important Conference Papers Database, China Dissertation Database, and online clinical trial registry websites were searched for published and unpublished randomized controlled trials (RCTs) of Chinese herbs for H1N1 influenza till 31 August, 2011. A total of 26 RCTs were identified and reviewed. Most of the RCTs were of high risk of bias with flawed study design and poor methodological quality. The combination of several Chinese herbal medicines with or without oseltamivir demonstrated positive effect on fever resolution, relief of symptoms, and global effectiveness rate compared to oseltamivir alone. However, only one herbal medicine showed positive effect on viral shedding. Most of the trials did not report adverse events, and the safety of herbal medicines is still uncertain.
ConclusionsSome Chinese herbal medicines demonstrated potential positive effect for 2009 type A H1N1 influenza; however, due to the lack of placebo controlled trial and lack of repeated test of the intervention, we could not draw confirmative conclusions on the beneficial effect of Chinese herbs for H1N1 influenza. More rigorous trials are warranted to support their clinical use.

研究背景：普遍认为中草药对甲型H1N1流感（type A H1N1 influenza）具有治疗效用。多项中草药已被中国政府批准推荐使用，截至目前，已有多项针对甲型H1N1流感的中草药临床试验相继开展。然而，目前尚无针对中草药用于甲型H1N1流感的获益与风险的经过严格评价的证据，如系统评价（systematic review）或荟萃分析（meta-analysis），无法为其临床应用及推荐使用提供科学依据。
方法与结果：截至2011年8月31日，检索CENTRAL数据库、MEDLINE数据库、EMBASE数据库、中国生物医学文献数据库（CBM）、中国知网（CNKI）、维普中文科技期刊数据库（VIP）、中国重要会议论文全文数据库、中国学位论文全文数据库以及在线临床试验注册网站，获取已发表及未发表的针对甲型H1N1流感的中草药随机对照试验（randomized controlled trials, RCTs）。最终共纳入26项RCTs并进行系统评价。其中绝大多数RCTs存在偏倚风险较高、研究设计存在缺陷以及方法学质量欠佳的问题。与单用奥司他韦（oseltamivir）相比，联合使用多种中草药（联用或不联用奥司他韦）在退热、症状缓解及总体有效率方面均表现出积极效果。但仅有1种中草药在病毒排毒方面展现出积极作用。绝大多数试验未报告不良事件，因此中草药的安全性仍有待明确。
结论：部分中草药对2009年甲型H1N1流感展现出潜在的积极疗效；但由于缺乏安慰剂对照试验以及干预措施的重复验证研究，目前无法就中草药用于甲型H1N1流感的获益效应得出确定性结论。亟需开展更高质量的临床试验，以为其临床应用提供可靠依据。