Essential Oil-Herbal Sachet Intervention for Sleep Quality and Anxiety in Maintenance Hemodialysis: A Single-Center Randomized Trial

Summary

This single-center randomized trial evaluated an olfactory intervention using an essential oil and herbal sachet in maintenance hemodialysis patients. The intervention was associated with improved self-reported sleep quality and anxiety, although larger controlled studies are needed.

Abstract

Sleep disturbance and anxiety are common in maintenance hemodialysis patients, yet sustained non-pharmacological management remains difficult in routine dialysis care. This single-center, open-label, parallel-group randomized trial evaluated whether a combined olfactory intervention using an essential-oil preparation and a traditional Chinese herbal sachet was associated with improved self-reported sleep quality and anxiety. Eighty-eight eligible patients with a baseline Pittsburgh Sleep Quality Index (PSQI) score >7 were recruited from Yongkang Hospital of Traditional Chinese Medicine between January 2022 and December 2023 and randomized 1:1 by random-number table to usual care or usual care plus the combined intervention. The trial was not prospectively registered, and participant and intervention-provider blinding was not feasible because of the odor-based intervention. The essential-oil preparation contained lavender essential oil, bergamot essential oil, and coconut oil in a 5:3:10 ratio and was used during dialysis and before sleep; the herbal sachet was placed near the pillow and replaced monthly. Outcomes were assessed using the PSQI and Hospital Anxiety and Depression Scale-Anxiety subscale (HADS-A) at baseline, day 7, day 15, month 1, and month 3. The primary endpoint was the between-group difference in PSQI global score at month 3. At month 3, the intervention group had lower PSQI scores than the control group (7.8 ± 2.6 vs. 13.8 ± 2.5; adjusted β, -5.37; 95% CI, -6.29 to -4.45; p < 0.001) and lower HADS-A scores (9.2 ± 2.1 vs. 11.8 ± 2.4; adjusted β, -2.61; 95% CI, -3.26 to -1.96; p. < 0.001). Sleep response occurred in 77.3% versus 31.8%, and anxiety response occurred in 68.2% versus 29.5%. Mean adherence was 86.7% for bedtime application and 83.4% for dialysis-session inhalation. Any adverse event was reported in 15.9% versus 6.8%, with no serious intervention-related adverse events. These preliminary findings require confirmation in larger controlled multicenter trials.

Introduction

Sleep disturbance and anxiety are highly prevalent among patients undergoing maintenance hemodialysis and are among the most burdensome non-survival outcomes in long-term renal replacement therapy¹. In this population, poor sleep rarely appears as an isolated complaint. It often develops within a broader symptom burden shaped by uremia-related discomfort, repeated dialysis scheduling, restricted daily activities, chronic disease uncertainty, and persistent emotional stress. Reduced sleep quality can impair daytime functioning, intensify fatigue, weaken coping ability, and compromise overall quality of life². Anxiety furt....

Protocol

This study was conducted in accordance with the Declaration of Helsinki and the institutional requirements of Yongkang Hospital of Traditional Chinese Medicine¹⁰. The study was approved by the Ethics Committee of Yongkang Hospital of Traditional Chinese Medicine in 2021. The approval document did not assign a separate approval number. Written informed consent was obtained from all participants before screening and enrollment. Participants were informed that participation was voluntary, refusal would not affect routine dialysis care, and withdrawal was permitted at any time. The reagents, chemicals, and tools used in the protocol are listed in t....

Results

Participant flow and baseline characteristics
A total of 104 patients undergoing maintenance hemodialysis were assessed for eligibility between January 2022 and December 2023. Sixteen patients were excluded before randomization because they did not meet the eligibility criteria or declined participation. The remaining 88 patients were randomized in a 1:1 ratio, with 44 assigned to the control group and 44 assigned to the intervention group. The participant flow is shown in Figure.......

Discussion

This single-center randomized controlled study evaluated a combined olfactory intervention consisting of dialysis-session essential-oil inhalation, bedtime external application with massage, and overnight exposure to a traditional Chinese herbal sachet in patients undergoing maintenance hemodialysis. Compared with routine care alone, the intervention group showed lower self-reported PSQI global scores at follow-up, with the primary month-3 comparison favoring the intervention group. HADS-A scores also decreased more in t.......

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
Acorus tatarinowii rhizome	Hospital pharmacy, Yongkang Hospital of Traditional Chinese Medicine	Not commercially applicable	Herbal sachet component; 6 g per sachet. Supplied as dried medicinal material through the hospital pharmacy.
Adjustable mechanical pipette, 0.5–5 mL	Eppendorf	3123000071	Used to measure lavender essential oil, bergamot essential oil, and coconut oil during batch preparation.
Adverse-event monitoring form	Study-generated document	Not commercially applicable	Used to record onset time, duration, severity, suspected relationship to intervention, management, and outcome of monitored symptoms.
Agastache rugosa herb	Hospital pharmacy, Yongkang Hospital of Traditional Chinese Medicine	Not commercially applicable	Herbal sachet component; 6 g per sachet. Supplied as dried medicinal material through the hospital pharmacy.
Albizia julibrissin flower	Hospital pharmacy, Yongkang Hospital of Traditional Chinese Medicine	Not commercially applicable	Herbal sachet component; 6 g per sachet. Supplied as dried medicinal material through the hospital pharmacy.
Amber glass dropper bottle, 10 mL	Fisher Scientific or equivalent laboratory supplier	03-339-23D or equivalent	Used to dispense the essential-oil preparation to participants. Amber glass was used to reduce light exposure.
Analytical balance, 220 g capacity, 0.001 g readability	OHAUS	PX223/E	Used to weigh dried herbal materials during sachet preparation.
Angelica dahurica root	Hospital pharmacy, Yongkang Hospital of Traditional Chinese Medicine	Not commercially applicable	Herbal sachet component; 6 g per sachet. Supplied as dried medicinal material through the hospital pharmacy.
Artemisia argyi leaf	Hospital pharmacy, Yongkang Hospital of Traditional Chinese Medicine	Not commercially applicable	Herbal sachet component; 30 g per sachet. Supplied as dried medicinal material through the hospital pharmacy.
Bergamot essential oil	Sigma-Aldrich / MilliporeSigma	W215309	Used as the bergamot component of the essential-oil preparation. Stored away from light and heat before use.
Breathable cotton sachet bag, approximately 8 cm × 10 cm	Hospital-prepared study material	Not commercially applicable	Used to package the dried herbal mixture. Each sachet was labeled with preparation and replacement dates and replaced every 30 days.
Case report form	Study-generated document	Not commercially applicable	Used to record eligibility, demographic data, dialysis information, concomitant medications, follow-up status, and withdrawal information.
Clove	Hospital pharmacy, Yongkang Hospital of Traditional Chinese Medicine	Not commercially applicable	Herbal sachet component; 6 g per sachet. Supplied as dried medicinal material through the hospital pharmacy.
Coconut oil	Sigma-Aldrich / MilliporeSigma	C1758	Used as the carrier oil in the essential-oil preparation.
Daily intervention adherence log	Study-generated document	Not commercially applicable	Used to record dialysis-session inhalation, bedtime application and massage, sachet use, sachet replacement, and discomfort.
Hospital Anxiety and Depression Scale-Anxiety subscale	GL Assessment	Licensed HADS record form/manual	Used to assess self-reported anxiety symptoms at baseline and follow-up.
IBM SPSS Statistics	IBM	Version 23.0	Used for descriptive statistics, baseline comparisons, mixed-effects models, responder analyses, sensitivity analyses, and multiple imputation.
Intervention dispensing log	Study-generated document	Not commercially applicable	Used to record essential-oil preparation date, participant study number, dispensing date, and sachet replacement date.
Lavender essential oil	Sigma-Aldrich / MilliporeSigma	W262218	Used as the lavender component of the essential-oil preparation. Mixed with bergamot essential oil and coconut oil at a 5:3:10 volume ratio.
Low-form glass beaker, 50 mL	VWR / Avantor	10754-946	Used for small-batch mixing of the essential-oil preparation.
Mint herb	Hospital pharmacy, Yongkang Hospital of Traditional Chinese Medicine	Not commercially applicable	Herbal sachet component; 6 g per sachet. Supplied as dried medicinal material through the hospital pharmacy.
Pittsburgh Sleep Quality Index	Original instrument source: Buysse et al.	Not commercially applicable	Used to assess self-reported sleep quality at baseline, day 7, day 15, month 1, and month 3. The validated Chinese version was used in questionnaire administration.
Random-number table	Study-generated document	Not commercially applicable	Used to generate the 1:1 allocation sequence before recruitment.
Rose flower	Hospital pharmacy, Yongkang Hospital of Traditional Chinese Medicine	Not commercially applicable	Herbal sachet component; 6 g per sachet. Supplied as dried medicinal material through the hospital pharmacy.
Sequentially numbered opaque sealed envelopes	Study-generated material	Not commercially applicable	Used for allocation concealment. Envelopes were opened only after eligibility confirmation and baseline assessment.
Sterile nonwoven gauze sponge, 2 × 2 in	Fisherbrand / Fisher Scientific	22-028-559	Used as the carrier pad for dialysis-session essential-oil inhalation. Two drops of essential-oil preparation were applied to the pad.
Tube Mill control batch mill	IKA	4180001	Used to process dried herbal materials into coarse powder before sachet packing.