Abstract
Background. Yangxue Qingnao granule (YQG) combined with antihypertensive drugs, a new integrative medicine therapy, has been widely used for essential hypertension (EH) in China. This study aims to assess the current clinical evidence of YQG combined with antihypertensive drugs for EH. Methods. Randomized controlled trials(RCTs) published between 1996 and 2012 on YQG combined with antihypertensive drugs versus antihypertensive drugs in treating EH were retrieved from six major electronic databases, including The Cochrane Library, PubMed, Chinese National Knowledge Infrastructure, Chinese Scientific Journal Database, Chinese Biomedical Literature Database, and Wanfang Data. Meta-analysis was performed on the overall effects on blood pressure. Results. Twelve randomized trials were included. Methodological quality of the trials was evaluated as generally low. Meta-analysis showed that YQG combined with antihypertensive drugs demonstrated potential effect for lowing either SBP (MD: -7.31 [-11.75, -2.87]; P = 0.001) or DBP (MD: -5.21 [-8.19, -2.24]; P = 0.0006) compared to antihypertensive drugs alone. Conclusions. It indicated that YQG combined with antihypertensive drugs is more effective than antihypertensive drugs alone in treating EH. However, more RCTs of larger scale, multicentre/country, longer follow-up periods, and higher quality are required to verify the efficacy of integrative medicine therapy over all antihypertensive therapies.