Sinclair Alison, Xie Xuanqian, Saab Lama, Dendukuri Nandini
Technology Assessment Unit, McGill University Health Centre, Montréal, Que.
CMAJ Open. 2016 Nov 24;4(4):E706-E718. doi: 10.9778/cmajo.20160087. eCollection 2016 Oct-Dec.
Recent meta-analyses of the efficacy of probiotics for preventing diarrhea associated with have concluded there is a large effect favouring probiotics. We reexamined this evidence, which contradicts the results of a more recent large randomized controlled trial that found no benefit of probiotics for preventing -associated diarrhea.
We performed a systematic review of the efficacy of treatment with probiotics for preventing nosocomial -associated diarrhea in adults and carried out a meta-analysis using a Bayesian hierarchical model. We used credibility analysis and meta-regression to characterize the heterogeneity between studies.
Ten studies met our inclusion criteria. The pooled risk ratio was highly statistically significant, at 0.25 (95% credible interval 0.08-0.47). However, the 95% prediction interval for the risk ratio in a future study, 0.02-1.34, was wider than the credible interval, owing to heterogeneity between studies. Furthermore, a credibility analysis showed that the strength of the evidence was weaker than the observed number of cases of -associated diarrhea across studies would suggest. Meta-regression suggested that the beneficial effect of probiotics was more likely to be reported in studies with an increased risk of -associated diarrhea in the control group, although this association was not statistically significant.
Accounting for between-study heterogeneity showed that there is considerable uncertainty regarding the apparently large efficacy estimate associated with probiotic treatment in preventing -associated diarrhea. Most studies to date have been carried out in populations with a low risk of -associated diarrhea, such that the evidence is inconclusive and inadequate to support a policy concerning routine use of probiotics in to prevent this condition.
近期关于益生菌预防[具体疾病]相关腹泻疗效的荟萃分析得出结论，认为益生菌有显著疗效。我们重新审视了这一证据，其与一项近期大型随机对照试验的结果相矛盾，该试验发现益生菌对预防[具体疾病]相关腹泻并无益处。
我们对成人使用益生菌预防医院获得性[具体疾病]相关腹泻的疗效进行了系统评价，并使用贝叶斯分层模型进行荟萃分析。我们采用可信度分析和荟萃回归来描述研究之间的异质性。
十项研究符合我们的纳入标准。汇总风险比具有高度统计学意义，为0.25（95%可信区间0.08 - 0.47）。然而，由于研究之间的异质性，未来研究中风险比的95%预测区间为0.02 - 1.34，比可信区间更宽。此外，可信度分析表明，证据强度低于各研究中观察到的[具体疾病]相关腹泻病例数所显示的强度。荟萃回归表明，在对照组中[具体疾病]相关腹泻风险增加的研究中，更有可能报告益生菌的有益效果，尽管这种关联无统计学意义。
考虑到研究间的异质性表明，对于益生菌治疗预防[具体疾病]相关腹泻的明显大疗效估计存在相当大的不确定性。迄今为止，大多数研究是在[具体疾病]相关腹泻风险较低的人群中进行的，因此证据尚无定论，不足以支持关于常规使用益生菌预防这种疾病的政策制定。
