The effectiveness of aromatic extract on insomnia: a meta-analysis

Insomnia is a global health issue that imposes social and economic burdens. Aromatherapy is regarded as a promising alternative medicine for improving sleep quality. This meta-analysis was conducted to explore the potential of aromatherapy for addressing insomnia.

Seven databases were searched for relevant randomized controlled trials (RCTs) from their inception through August 12, 2023. Data were synthesized using random-effect pairwise meta-analysis, with standardized mean difference (SMD) and 95% confidence interval (CI) reported. The risk of bias of each RCT was appraised using the Cochrane risk of bias tool. Subgroup and sensitivity analysis, publication bias diagnosis were also performed.

A total of 14 studies with 1043 participants were included. The meta-analysis revealed a significant difference between the intervention and control groups (SMD: -1.63, 95% CI: -2.20 to -1.04). Sensitivity analysis showed that, whichever study was omitted, the conclusions of the remaining studies did not reverse. Among the 14 RCTs included, 6 were deemed to have a low overall risk of bias, and 8 were found to have some concerns. Subgroup analysis revealed that Iran had a more significant therapeutic effect than other regions. The effects of rose and citrus aurantium are more obvious than those of lavender. The different treatments in the control groups, intervention durations and sleep quality questionnaires had impacts on therapeutic effects, while discrepancies were not significant for different health conditions.

Aromatic essential oil has a significant therapeutic effect on insomnia. Further research on the mechanisms and guidelines for implementing aromatherapy is needed. This meta-analysis has been registered in PROSPERO with the ID CRD42023454070.