Comparative efficacy of hypnotics in young and middle-aged adults with insomnia: a systematic review and network meta-analysis

Objective/background: Insomnia is highly prevalent in modern society. However, the hierarchical selection of hypnotics in young and middle-aged adults with insomnia remains unclear. We aimed to compare the efficacy and daytime drowsiness associated with different hypnotics for treating insomnia in young and middle-aged adults. Methods: We searched Embase, PubMed, Cochrane Library, and ProQuest Dissertations and Theses A&I databases from inception until December 15, 2021. We also manually searched reference lists and relevant publications. The literature search, data collection, and risk of bias evaluation were all carried out separately by pairs of reviewers. We included randomized control trials (RCTs) that compared hypnotics approved by the Food and Drug Administration. The R and Stata software were both used to perform the meta-analysis. Results: In total, 117 RCTs comprising 22,508 participants with the age of 18 to 65 years were included. Assessment of the efficacy of the hypnotics and adverse events (drowsiness) revealed that zolpidem improved all objective sleep parameters (oTST, oSOL, oWASO, and oSE), zopiclone increased oTST and oSE and reduced oSOL, and daridorexant increased oTST and reduced oWASO. Regarding subjective sleep outcomes, zolpidem exhibited beneficial effects on sTST, sSOL, and sWASO. Zaleplon reduced sSOL, and zopiclone was the recommended hypnotic for improving SQ. Zolpidem was associated with drowsiness effect (odds ratio = 1.82; 95% confidence interval = 1.25 to 2.65). The results of sensitivity analysis remained unchanged after the exclusion of studies reporting long-term effects. Conclusion: Zolpidem is recommended for managing sleep-onset insomnia and sleep maintenance insomnia but should be used with caution because of daytime drowsiness effects. Daridorexant is recommended as a promising agent for managing sleep maintenance insomnia.