Niuhuang Jiangya Preparation (a traditional Chinese patent medicine) for essential hypertension: A systematic review

Niuhuang Jiangya Preparation (NHJYP) is one of the most commonly used traditional Chinese patent medicines for essential hypertension (EH) in China. Our meta-analysis performed a systematic evaluation on the therapeutic efficacy and safety of NHJYP for EH.Systematic review and meta-analysis.PubMed, Embase, the Cochrane library, CNKI,VIP, Sinomed, and Wanfang Database were searched up to June 2015. Randomized controlled trials (RCTs) comparing NHJYP or combined with western antihypertensive drugs (WAD) versus WAD were included. Quality of each trial was assessed according to the Cochrane Reviewers' Handbook 5. 1.0. Statistical software (RevMan 5.3) was used for data analysis. The primary outcome was categorical or continuous blood pressure, and the secondary outcome was Traditional Chinese Medicine (TCM) syndrome.12 RCTs including 1651 cases were identified. The methodological quality of trials was low. Meta-analysis showed that, firstly, NHJYP used alone compared with WAD had no significant effect on BP reduction; however, subgroup analysis was used based on whether apply TCM diagnostic criteria in recruitment. It was suggested that, for population that applied TCM diagnostic criteria, RR=1.35,95% CI:1.17-1.56，P<0.0001; for population that didn't apply TCM diagnostic criteria, RR=0.96,95% CI：0.70-1.33，P=0.81.Reduction in systolic blood pressure (SBP) levels showed similar results. But there was no significant difference in improving diastolic blood pressure (DBP). Secondly, we found that NHJYP plus WAD probably lower BP (RR=1.13，95% CI:1.03-1.24,P=0.01)and improve TCM symptoms than WAD only. And subgroup analysis suggested significant BP reduction effect for population that applied TCM diagnostic. No serious adverse events were reported.Our review indicated that NHJYP has some beneficial effects in EH patients with liver-yang hyperactivity and abundant phlegm-heat syndrome. However, the evidence is not reliable enough. To produce definite evidence, more rigorously designed trials are needed.