Essential oil and herbal sachet linked to improved sleep and lower anxiety in dialysis patients
An 88-patient randomized trial found that a combined olfactory intervention using lavender and bergamot essential oils plus a traditional Chinese herbal sachet was associated with significantly improved sleep quality and reduced anxiety symptoms in maintenance hemodialysis patients over 3 months.
Sleep disturbance and anxiety are widespread among patients undergoing maintenance hemodialysis, yet non-pharmacological options integrated into routine care remain limited. Researchers at Yongkang Hospital of Traditional Chinese Medicine conducted a single-center, open-label randomized trial of 88 hemodialysis patients with baseline sleep disturbance (Pittsburgh Sleep Quality Index scores >7) between January 2022 and December 2023.
Participants were randomly assigned to usual care alone (n=44) or usual care plus a combined intervention: a blend of lavender, bergamot, and coconut oil applied during dialysis sessions and before bed, plus a monthly-replaced herbal sachet placed near the pillow. At 3 months, the intervention group had significantly lower sleep quality scores (7.8 vs. 13.8; adjusted difference −5.37, 95% CI −6.29 to −4.45, p<0.001) and anxiety scores (9.2 vs. 11.8 on the Hospital Anxiety and Depression Scale; adjusted difference −2.61, 95% CI −3.26 to −1.96, p<0.001). Seventy-seven percent of the intervention group showed sleep improvement compared with 32% of controls; 68% showed anxiety improvement versus 30% of controls. Mean adherence was high (87% for bedtime, 83% for dialysis-session use). Adverse events were reported in 16% of the intervention group and 7% of controls, with no serious events. However, the trial was not prospectively registered and lacked blinding, which limits confidence in the findings.
The study's effect sizes are substantial: a 6-point difference in the sleep quality index (where lower is better) and a 2.6-point difference in anxiety represent clinically meaningful reductions. The mechanism likely involves olfactory pathways—lavender and bergamot have been used traditionally for calming effects and may influence sleep-wake regulation through limbic system stimulation. Subgroup analysis and mechanistic specificity were not reported, so it remains unclear which components (essential oil vs. herbal sachet, or the combination) drove the benefit, or whether effects were similar across age, sex, or dialysis vintage. The lack of prospective registration and open-label design (participants and providers knew who received the intervention) raises the possibility of placebo or expectancy effects, which may inflate perceived benefit for subjective outcomes like sleep quality and anxiety. The comparator was usual care, not an active control (e.g., an inert sachet), making it impossible to separate the olfactory effect from ritual or attention. Adherence was notably high despite the effort required, suggesting patients found the intervention tolerable and possibly valued it.
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Open in Cadence →References
- Essential Oil-herbal Sachet Intervention for Sleep Quality and Anxiety in Maintenance Hemodialysis: A Single-center Randomized Trial. — Journal of visualized experiments : JoVE (Read the original)