Herbal medicine (Gan Mai Da Zao decoction) for depression: A systematic review and meta-analysis of randomized controlled trials

• Gan Mai Da Zao (GMDZ) decoction is one of the most famous Chinese herbal medicine for depression.
• One recent systematic review of GMDZ decoction suggested that GMDZ might be beneficial as anti-depressants. However, this review analysis inappropriate and the information was not complete.
• Thirteen RCTs met our inclusion criteria. All of the included RCTs had a high risk of bias across their domains.
• Our systematic review and meta-analysis failed to provide suggestive evidence of the superiority of GMDZ decoction over anti-depressant therapies for major depression, post-surgical depression, and elderly depression except stroke depression.

The objective of this review was to analyze the trial data on the efficacy and safety of Gan Mai Da Zao (GMDZ) decoction for depression. PubMed, the Cochrane Library, and EMBASE, AMED, Korea Med, DBPIA, OASIS, RISS, KISS, CNKI, Wan Fang Database, and VIP were searched through to May 2014. Randomized controlled trials (RCTs) testing GMDZ decoction for any type of depression were considered. All RCTs of GMDZ decoction or modified GMDZ decoction were included. Data were extracted by 2 independent reviewers. Meta-analysis was used for the pooled data. A total of 298 potentially relevant studies were identified, and 13 RCTs met our inclusion criteria. All of the included RCTs had a high risk of bias across their domains. Three RCTs failed to show favorable effects of GMDZ decoction on response rate or HAMD score in major depression. One RCT showed a beneficial effect of GMDZ decoction on response rate in post-surgical depression, while another failed to do so. Two studies showed favorable effects on response rate in post-stroke depression, while another two failed to do so. A meta-analysis, however, showed that GMDZ decoction produced better response rates than anti-depressants in post-stroke depression (RR: 1.17, I2 = 15%). One trial failed to show any beneficial effects of GMDZ decoction on response rate or HAMD score in depression in an elderly sample. Two trials tested GMDZ decoction in combination with anti-depressants but failed to show effects on response rate in major depression, while another did show beneficial effects on response rate in post-stroke depression. In summary, our systematic review and meta-analysis failed to provide evidence of the superiority of GMDZ decoction over anti-depressant therapies for major depression, post-surgical depression, or depression in the elderly, although there was evidence of an effect in post-stroke depression. The quality of evidence for this finding was low, however, because of a high risk of bias.