[Evidence mapping of clinical studies on 23 commonly used Chinese patent medicines for treating insomnia]

Evidence mapping was performed to systematically search and review the clinical studies about the treatment of insomnia with Chinese patent medicines. The evidence distribution in this field was analyzed and the problems of the studies were summarized. Chinese-and English-language articles of the studies involving the Chinese patent medicines specified in three national drug catalogs for the treatment of insomnia were searched against the databases with the time interval from inception to August 2023. Figures and tables were established to present the results. Finally, 23 Chinese patent medicines were screened out, which were mentioned in 299 articles involving 236 randomized controlled trials(RCTs), 35 non-randomized controlled trials(non-RCTs), 7 retrospective studies, 17 systematic reviews/Meta-analysis, and 4 guidelines/expert recommendations or consensus. Bailemian Capsules, Wuling Capsules, and Yangxue Qingnao Granules were mentioned in a large proportion of articles. The outcome indicators included sleep rating scale, clinical response rate, safety indicators, and anxiety and depression scores. The results showed that the studies about the treatment of insomnia with Chinese patent medicines were growing. However, there was a scarcity of research evidence, and the available studies were single-center with small sample sizes and short periods. These studies spanned broad clinical scopes with inadequately emphasized advantages of TCM and insufficient outcome indicators about quality of life, follow-up, and recurrence rate. RCT exhibited a high risk of bias, and the systematic reviews/Meta-analysis demonstrated low overall quality. The retrospective studies received suboptimal scores, and the non-RCT failed to mention follow-up time, loss rate to follow-up, and sample size estimations, which compromised result reliability. It is recommended that the research protocol for Chinese patent medicines in treating insomnia should adhere to the clinical research standards of TCM. The TCM syndrome score can serves as a crucial outcome measure, and emphasis should be placed on patients' quality of life, follow-up, and recurrence prevention. Measures should be taken to enhance the accessibility and affordability of Chinese patent medicines and strengthen the connection between medical insurance policies and the policies pertaining to Chinese patent medicines. Furthermore, it is advisable to reasonably increase the inclusion of Chinese patent medicines with well-established efficacy and safety evidence in the category A list of medical insurance.