The effect of chinese herbal medicine Banxia Baizhu Tianma Decoction for the treatment of vertebrobasilar insufficiency vertigo: A systematic review and meta-analysis of randomized controlled trials.

OBJECTIVES: Banxia Baizhu Tianma Decoction (BBTD) is widely used to treat vertebrobasilar insufficiency vertigo (VBIV) in China, but its efficacy remains largely unexplored. We systemically summarized relevant evidence from randomized controlled trials (RCTs) to assess the therapeutic effect of BBTD.

METHODS: Seven electronic databases were searched for relevant electronic studies published before July 2016. We evaluated RCTs that compared BBTD, anti-vertigo drugs and a combination of BBTD and anti-vertigo drugs. We performed a meta-analysis in accordance with the Cochrane Collaboration criteria. The outcomes were clinical efficacy (CE), blood flow velocity of the vertebrobasilar artery by transcranial Doppler (TCD), and adverse effects.

RESULTS: Twenty-seven studies with a total of 2796 patients were identified. Compared with anti-vertigo drugs, BBTD showed slight effects on CE (n=350; RR, 1.09; 95% CI, 1.01-1.18; p=0.03; I(2)=0%); however, BBTD plus anti-vertigo drugs (BPAD) significantly improved the clinical efficacy (n=2446; RR, 1.20; 95% CI, 1.16-1.24; p<0.00001; I(2)=0%) and accelerated the blood flow velocity of the left vertebral artery (LVA) (n=1444; WMD, 5.21cm/s; 95% CI, 3.72-6.70cm/s; p<0.00001; I(2)=91%), the blood flow velocity of the right vertebral artery (RVA) (n=1444; WMD, 5.45cm/s; 95% CI, 4.02-6.88cm/s; p<0.00001; I(2)=89%), and the blood flow velocity of the basilar artery (BA) (n=1872; WMD, 5.20cm/s; 95% CI, 3.86-6.54cm/s; p<0.00001; I(2)=90%). Adverse effects were mentioned in six studies.

CONCLUSIONS: The current evidence indicates that BPAD is effective for the treatment of VBIV, but the efficacy and safety of BBTD is uncertain because of the limited number of trials and low methodological quality. Hence, high-quality and adequately powered RCTs are warranted.