[Systematic review and Meta-analysis of efficacy and safety of gastrodin in treatment of tension-type headache].

The efficacy of gastrodin as a Chinese herbal medicine extract in the treatment of tension-type headache has been confirmed. This paper systematically reviewed the efficacy and safety of gastrodin in the treatment of tension-type headache, aiming to provide a new choice for the treatment of this disease. In this study, four Chinese databases, four English databases and two trial registries were searched from the date of establishment to September 2020. The related randomized controlled trials(RCTs) were screened out according to the predetermined criteria. The bias risk assessment tool developed by Cochrane collaboration was used to evaluate the quality of the reports. RevMan 5.4.1 was used for Meta-analysis, and GRADE system for the evidence-based evaluation on the quality of outcome indicators. A total of 177 articles were retrieved and 8 articles were finally included for analysis, with a total sample size of 1 091 cases, which included 565 cases in the treatment group and 526 cases in the control group. The overall quality of included stu-dies was not high. The results of Meta-analysis are as follows:(1)In terms of headache frequency, gastrodin group was better than wes-tern medicine group(MD=-2.90, 95%CI[-3.76,-2.03], P<0.000 01).(2)In terms of number of abnormal blood vessels in TCD, gastrodin group was better than western medicine group(MD=-88.96, 95%CI[-102.36,-75.55], P<0.000 01).(3)In terms of effective rate, gastrodin group was better than western medicine group(RR=1.47, 95%CI[1.29, 1.68], P<0.000 01). The results of subgroup analysis are as follows:(1)Effective rate based on age, for the patients upper age limit 40-46 years old, gastro-din group was better than western medicine group(RR=1.69, 95%CI[1.50, 1.90], P<0.000 01); for the patients upper age limit 55-60 years old, gastrodin group was better than western medicine group(RR=1.27, 95%CI[1.16, 1.38], P<0.000 01).(2)Effective rate based on dosage form, both the gastrodin capsules and injection groups were better than western medicine group(RR_(capsules)=1.42, 95%CI[1.08, 1.88], P=0.01; RR_(injection)=1.50, 95%CI[1.26, 1.77], P<0.000 01). GRADE evaluation showed that the above outcomes had low quality of evidence. Only one article detailed the occurrence of adverse reactions and thus the present study cannot make a positive conclusion on the safety of gastrodin in the treatment of tension-type headache. The small number and low quality of the included reports affected the reliability of the results. In the future, more high-quality randomized controlled trails are needed to improve the evaluation on the efficacy and safety of gastrodin in the treatment of tension-type headache.