Xiaoxuming decoction for acute ischemic stroke: a systematic review and meta-analysis.

Xiaoxuming decoction (XXMD) is a well-known traditional Chinese herbal prescription in treatment of patients with stroke. The objective of this study is to assess the efficacy and safety of XXMD for acute ischemic stroke.A systematic literature search was conducted in 6 databases until June 2012 to identify randomized controlled trials (RCTs) of XXMD for acute ischemic stroke compared with western conventional medicine (WCM). The primary outcome measures were National Institutes of Health Stroke Scale (NIHSS) scores and modified Rankin Scale (mRS) scores. The secondary outcome measures were the clinical effective rate and adverse events at the end of treatment course. The methodological quality of RCTs was assessed independently using 12-item criteria according to the Cochrane Back Review Group. All data were analyzed using Review Manager 5.0 software.Eight RCTs with 601 individuals published from 1992 to 2012 were identified. The studies were deemed to have a high risk of bias. Compared with WCM, 1 RCT showed significant effects of XXMD for improving mRS after stroke (p<0.05); 3 RCTs for improving NIHSS scores [n=186, weighted mean difference (WMD): -1.86, 95% CI: -3.25 to -0.48, z=2.63, p<0.01]; 7 RCTs for improving the clinical effective rate [n=531, risk ratio (RR)=1.17, 95% CI, 1.09 to 1.26, z=4.38, p<0.01]. Five trials contained safety assessments and stated that no adverse event was found, whereas the other 3 trials did not provide the information about adverse events.This systematic review showed positive but weak evidence of XXMD for acute ischemic stroke because of the poor methodological quality and the small quantity of the included trials. The difficulties of fitting Chinese herbal medicine (CHM) into the double blinded RCTs have raised as follows: (A) traditional Chinese medicine (TCM) as whole systems of healthcare offers unique methodological and theoretical challenges for RCTs; (B) suspicions against the placebo and unwillingness to stop taking other CHMs make recruitment more difficulty, time-consumption, and cost; (C) the shortcomings of the TCM diagnostic process includes the lack of standardization in terminology, disagreement of pattern differentiation (Bianzheng), and neglect of formula corresponding to syndrome (TCM Zheng); (D) It is difficult to design credible herbal placebos with similar appearance, smells and tastes to the experimental CHM and at the same time is absent of any pharmacological activity; (E) the achieving efficacy of CHM complex interventions is often nonspecific and the outcome measures is subjective using Chinese quantitative instrument.