Lavender essential oil on postmenopausal women with insomnia: Double-blind randomized trial

Lavender improves sleep through olfactory perception and GABAergic neurons of the central amygdala

ETHNOPHARMACOLOGICAL RELEVANCE

The use of lavender as sleep aid or hypnotic agent can be traced back as early as ancient Romans and Greeks. Yet, objective experimental data on whether and how lavender enhances sleep duration or/and sleep quality remain lacking.

AIM OF THE STUDY

We aimed to characterize the sleep-wake regulating effects of lavender in the mouse and to demonstrate the brain targets and neural circuits involved.

MATERIALS AND METHODS

A self-made precise odor delivery system combined with chronic polysomnographic recordings was employed to assess the sleep-wake effects of inhalation with lavender essential oil (LEO, extracted from lavender) and its different constituents during the light and dark phases in free-moving C57BL/6J mice. Neuroviral labeling, in situ hybridization and pharmacogenetics were combined to identify the neural circuits and targets involved. Finally, an insomniac model of DL-4-Chlorophenylalanine (PCPA)-treated mice was established to examine the sleep-inducing potential of LEO.

RESULTS

We found that inhalation of LEO with a concentration at 25.0% during the light (inactive) phase significantly shortened the latency to non-rapid eye movement (NREM) sleep, increased the total amount of NREM sleep at the expense of wakefulness (W), and enhanced cortical EEG slow wave activities, notably delta power spectra density. We further identified linalool, d-limonene, 1,8-cineole, linalyl acetate and terpinene-4-ol as the major effective sleep-promoting monomer components. Importantly, we found that LEO no longer produced any of the above sleep-promoting effect following either nasal injection of zinc sulfate which interrupts the olfactory pathway, or pharmacogenetics silencing of central amygdala GABAergic neurons. Finally, LEO reestablished NREM sleep with short latency in PCPA-treated insomniac mice, effects comparable with those induced by a potent sedative diazepam.

CONCLUSIONS

We have characterized the quantitative and qualitative sleep-promoting effects of LEO and its effective components via the olfactory pathway and central amygdala GABA neuronal targets. The hypnotic property of LEO is reinforced by its ability to restore sleep in insomnia. Our study thus establishes a neurobiological basis for aromatherapy of sleep disorders using lavender.

The moderating effect of alternate Mediterranean diet on the association between sedentary behavior and insomnia in postmenopausal women

Aim

The study aimed to explore the moderating role of the alternate Mediterranean diet (aMED) adherence on the association between sedentary behavior and insomnia symptoms in postmenopausal women.

Methods

Data regarding postmenopausal women were obtained for this cross-sectional study from the National Health and Nutrition Examination Survey (NHANES) 2005-2008. Sedentary behavior and insomnia symptoms were assessed using the questionnaire. aMED adherence was evaluated according to 24-h dietary recalls. Weighted univariate logistic regression models were utilized to screen potential covariates. The relationship between sedentary behavior, aMED adherence, and insomnia symptoms was explored using weighted univariate and multivariate logistic regression models. All results were expressed as odds ratios (ORs) and 95% confidence intervals (CIs).

Results

A total of 1,793 postmenopausal women were included in the final analysis. Of them, 643 (37.56%) reported experiencing insomnia symptoms. Among the postmenopausal women, sedentary time of >8 h was associated with insomnia symptoms (OR = 1.41, 95% CI = 1.01-1.96), prolonged nocturnal awakening (OR = 1.38, 95% CI = 1.06-1.79), and undesired early morning awakening (OR = 1.59, 95% CI = 1.09-2.30). No association was observed between adherence to the aMED and insomnia symptoms (OR = 1.05, 95% CI: 0.77-1.44). Among the postmenopausal women with lower adherence to the aMED, the odds of insomnia symptoms were higher in those with sedentary time ≥8 h (OR = 1.63, 95% CI: 1.02-2.62). Similarly, in the participants with low aMED adherence, sedentary time ≥8 h was also associated with prolonged nocturnal awakening (OR = 1.90, 95% CI = 1.27-2.83) and undesired early morning awakening (OR = 1.85, 95% CI = 1.09-3.16).

Conclusion

Adherence to the aMED modulates the association between sedentary behavior and insomnia symptoms in postmenopausal women. Interventions targeting sedentary behavior and dietary patterns may improve sleep quality and overall health in postmenopausal women.

The Role of Essential Oils on Sleep Quality and Other Sleep-related Issues: Evidence from Clinical Trials

Essential oils (EOs) are a volatile mixture of bioactive compounds extracted from aromatic plants. The composition of EOs varies, which majorly depends on the extraction methods and plant parts. Aromatherapy using EOs has been reported for its several beneficial effects in humans. Aromatherapy is considered a complementary and/ or adjuvant therapeutic approach for treating several illnesses, especially to improve mental health and well-being. The incidence of sleep disorders, specifically insomnia, is nowadays increased, possibly due to urbanization and lifestyle. The studies showed that EOs-based treatments using lavender EO, bergamot EO, cinnamon EO, and rosemary EO (alone or in combinations) could improve sleep quality, duration, and deprivation in healthy subjects and patients, those who suffer from sleep-related issues. The current manuscript details the outcomes of EO-based treatments on the sleep quality of humans and the possible mechanisms associated with the health-promoting properties of EOs. Also, the toxicity and adverse effects of EOs have been discussed. The study indicated that EOs are potent adjuvant therapeutic candidates to manage mood-associated complications in humans. Moreover, the aromatherapeutic field requires detailed studies on toxicity and dose determination, which could provide safe and effective therapeutic results.

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

PURPOSE

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.

METHODS

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.

RESULTS

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.

CONCLUSION

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.

Lavender essential oil alleviates depressive-like behavior in alcohol-withdrawn rats: Insights from gut metabolites and hippocampal transcriptome analysis

Lavender, an aromatic plant with a history dating back to ancient Egypt and Greece, is consumed because of its diverse pharmacological properties, including sedation, sleep aid, and antidepressant effects. However, the mechanisms underlying these antidepressant properties remain unclear. In this study, we explored the impact of lavender essential oil (LEO) inhalation on the diversity of gut microbiota, metabolites, and differential gene expression in the hippocampus of alcohol-withdrawn depressive rats. Additionally, we examined alterations in the hippocampal transient receptor potential (TRP) channel-mediated inflammatory regulation within the brain-gut axis of depressive rats. The results demonstrated a significant decrease in sucrose preference, diminished activity in the central zone of the open field test, and prolonged immobility time in the forced swim test in alcohol-withdrawn depressive rats, indicating the amelioration of depressive states following lavender essential oil inhalation. 16 S rDNA sequencing analysis revealed a significant reduction in Bacteroidota and Muribaculaceae in the gut of alcohol-withdrawn depressive rats, whereas lavender essential oil significantly increased the relative abundance of Muribaculaceae and other bacterial species. Metabolomic analysis identified 646 distinct metabolites as highly correlated biomarkers between the model and lavender essential oil groups. Furthermore, lavender essential oil inhalation significantly attenuated hippocampal inflammatory factors IL-2, IL-6, IL-1β, and TNF-α. This study identified elevated expression of Trpv4 and Calml4 in the hippocampal region of alcohol-withdrawn depressed rats and showed that lavender essential oil inhalation regulated aberrantly expressed genes. Our research suggests that lavender essential oil downregulates Trpv4, modulates inflammatory factors, and alleviates depressive-like behavior in alcohol withdrawal rats.

Sleep During Menopause

Postmenopause is defined retrospectively after 12 consecutive months of amenorrhea. It represents the end of the reproductive period and ovarian failure. A decrease in estrogen leads to several changes in the short and long term. Among the early changes, vasomotor symptoms (hot flashes) are particularly common, occurring in about 70% of women. In addition, there are changes in mood, anxiety, depression, and insomnia. Insomnia occurs in almost 60% of postmenopausal women. Psychosocial aspects may also affect sleep. Proper diagnosis may lead to adequate treatment of sleep disturbances during menopause. Hormonal or other complementary therapies can improve sleep quality.

The Effects of Inhalational Lavender Essential Oil Aromatherapy on Sleep Quality in Hemodialysis Patients: A Before-and-After-Intervention Trial

One of the most essential physical prerequisites for human survival is sleep. Patients undergoing hemodialysis often experience a lack of sleep, and it is one of the decisive variables in dialysis patients' quality of life. The objective of this study was to assess the effects of inhaling lavender essential oil on sleep quality in hemodialysis patients. A total of 30 patients were enrolled in the before-and-after intervention trial, which took place in a tertiary care hospital's dialysis unit. The study participants were selected using the purposive sampling technique and they received lavender oil inhalation therapy. The sleep quality was measured using the Pittsburgh Sleep Quality Index. The mean age of the participants was 55.11 (SD = 8.45) years. The mean posttherapy Pittsburgh Global Sleep Quality Index score was 8.8 ± 1.89 compared with the pretherapy score of 14.73 ± 1.53. Patients undergoing hemodialysis experienced a substantial improvement in sleep quality ( P < .05). Aromatherapy using lavender oil is effective in enhancing sleep quality in hemodialysis patients.

Relieving psychological stress and improving sleep quality by bergamot essential oil use before bedtime and upon awakening: A randomized crossover trial

OBJECTIVES

The COVID-19 pandemic increased psychological stress and decreased sleep quality, especially among young people. Aromatherapy alleviates psychological stress, and bergamot essential oil helps improve depression. This study aimed to verify whether bergamot essential oil use alleviates psychological stress due to the COVID-19 pandemic and improves sleep quality and morning wakefulness.

DESIGN

A placebo-controlled, randomized, open-label, two-arm, two-period crossover trial.

INTERVENTIONS

Each intervention period was 1 week, with a 1-week washout period between the two periods. Participants used a bergamot or placebo spray before bedtime and upon awakening in each period.

MAIN OUTCOME MEASURES

The primary outcome measures were sleep quality and morning wakefulness, assessed using the Ogri-Shirakawa-Azumi sleep inventory MA version (OSA-MA). The secondary outcome measures were depression, anxiety, and stress, assessed using the Depression Anxiety Stress Scales-21 (DASS-21).

RESULTS

A total of 48 university students participated in the study. A significant improvement was observed in "sleepiness on rising," "refreshing on rising," and "sleep length" in the bergamot group. Additionally, a significant improvement was observed in depression, anxiety, and stress.

CONCLUSION

Using bergamot essential oil before bedtime helps relax the mind and body and provides sound sleep. It also improves mood and wakefulness when used upon awakening. Using aromatic essential oils is expected to relieve psychological stress and improve sleep quality and morning wakefulness.

The immediate effects of lavender-based essential oil inhalation on subsequent polysomnography in people with poor sleep quality

BACKGROUND

Although aromatherapy is considered an adjuvant therapy to promote sleep quality, few objective sleep testing instruments can confirm the effects of aromatherapy on sleep physiology. The purpose of this study was to confirm and compare the immediate effects of a single lavender essential oil (SLEO) group to a complex lavender essential oil (CLEO) group by objective polysomnography (PSG) recordings.

METHODS

Participants were randomly divided into the SLEO group and CLEO group in this single-blind trial to explore the sleep effect of essential oil aroma. All the participants completed the sleep-related questionnaires and underwent two consecutive nights of PSG recordings, who had one night without aromatherapy and one night with one of the two aromas randomly assigned to them.

RESULTS

Total of 53 participants were recruited for this study, 25 participants were in the SLEO group, and 28 were in the CLEO group. Baseline characteristics and sleep-related questionnaires were similar in both groups. Both SLEO and CLEO extended the total sleep time (TST) (Δ = 43.42 and 23.75 minutes, respectively) and sleep period time (SPT) (Δ = 38.86 and 24.07 minutes, respectively). The SLEO group further improved sleep efficiency and increased the amounts of non-rapid eye movement (NREM) and rapid eye movement (REM) sleep and decreased spontaneous arousals. However, there was no significant difference in PSG parameters between the SLEO and CLEO groups.

CONCLUSION

Both SLEO and CLEO extended TST and SPT, with no significant differences between these two groups. These results warrant practical applications and merit future studies (Clinical trial registration: ClinicalTrials.gov : NCT03933553).

Natural essential oils derived from herbal medicines: A promising therapy strategy for treating cognitive impairment

Cognitive impairment (CI), mainly Alzheimer’s disease (AD), continues to increase in prevalence and is emerging as one of the major health problems in society. However, until now, there are no first-line therapeutic agents for the allopathic treatment or reversal of the disease course. Therefore, the development of therapeutic modalities or drugs that are effective, easy to use, and suitable for long-term administration is important for the treatment of CI such as AD. Essential oils (EOs) extracted from natural herbs have a wide range of pharmacological components, low toxicity, and wide sources, In this review, we list the history of using volatile oils against cognitive disorders in several countries, summarize EOs and monomeric components with cognitive improvement effects, and find that they mainly act by attenuating the neurotoxicity of amyloid beta, anti-oxidative stress, modulating the central cholinergic system, and improving microglia-mediated neuroinflammation. And combined with aromatherapy, the unique advantages and potential of natural EOs in the treatment of AD and other disorders were discussed. This review hopes to provide scientific basis and new ideas for the development and application of natural medicine EOs in the treatment of CI.

Common herbs for stress: The science and strategy of a botanical medicine approach to self-care

Frontline healthcare workers have reported elevated levels of stress and increase prevalence of burnout symptoms since the onset of the COVID-19 pandemic. With these heightened levels of stress and burnout comes a need for more evidence-based interventions to address these symptoms earlier, in both a safe and effective way. Some common botanical medicines have a measurable effect on perceived stress, neurotransmitter levels, and circulating cortisol levels indicating their ability to modify the stress response. Botanical medicines are often relatively low cost, increasingly available in retail stores and online marketplaces, and show relatively low reports of adverse effects, making these medicinal herbs an important option for addressing work-related stress for healthcare workers.

Association between night pain and quality of life in women: A general population sleep study

BACKGROUND

Women with pain present decreased sleep duration and quality of life, but little is known about the consequences of nighttime pain on overall health. Our goal was to compare levels of anxiety, depression and fatigue in women with pain during the night with those without pain. We hypothesized that pain perception is associated with the worsening of fatigue and mood.

METHODS

In total, 244 women aged 20-80 years who took part in the Epidemiologic Sleep Study (EPISONO) met the inclusion criteria, 85 in the self-reported pain group and 171 in the control group. Participants were assigned to the pain group if they both responded (i) they generally had pain, according to Pre-Sleep Questionnaire (PSQ) and (ii) their pain generally interfered with their sleep 3 or more times a week, according to Pittsburg Sleep Quality Index (PSQI). Those who answered negatively to both questions were allocated to the control group. All participants underwent a full night laboratory polysomnography, and completed questionnaires related to fatigue, depression, anxiety and quality of life.

RESULTS

Pain group participants had a significantly lower perception of quality of life, and significantly higher levels of fatigue (5.4 times), anxiety and depression. Pain perception was also correlated to levels of anxiety and depression in the psychological (r_s  = -0.463, -0.607, respectively) and social (r_s  = -0.423, -0.438, respectively) quality of life domains.

CONCLUSIONS

Nighttime pain in women was associated with decreased quality of life, worsening mood and fatigue. Our data shows the importance of investigating pain and its deleterious effects on women's health.

SIGNIFICANCE

Our study highlights that women experiencing nighttime pain also reported worse mood outcomes and decreased quality of life, regardless of the level and type of pain. Our data, based on association analysis and not investigating causality, suggest it is important to consider nighttime pain in clinical care to improve quality of life and general health.

Phytotherapeutic alternatives for neurodegenerative dementias: Scientific review, discussion and therapeutic proposal

The incidence and prevalence of age-related neurodegenerative dementias have been increasing. There is no curative therapy and conventional drug treatment can cause problems for patients. Medicinal plants traditionally used for problems associated with ageing are emerging as a therapeutic resource. The main aim is to give a proposal for use and future research based on scientific knowledge and tradition. A literature search was conducted in several searchable databases. The keywords used were related to neurodegenerative dementias, ageing and medicinal plants. Boolean operators and filters were used to focus the search. As a result, there is current clinical and preclinical scientific information on 49 species used in traditional medicine for ageing-related problems, including neurodegenerative dementias. There are preclinical and clinical scientific evidences on their properties against protein aggregates in the central nervous system and their effects on neuroinflammation, apoptosis dysregulation, mitochondrial dysfunction, gabaergic, glutamatergic and dopaminergic systems alterations, monoamine oxidase alterations, serotonin depletion and oestrogenic protection. In conclusion, the potential therapeutic effect of the different medicinal plants depends on the type of neurodegenerative dementia and its stage of development, but more clinical and preclinical research is needed to find better, safer and more effective treatments.

Effects of Nonpharmacological Interventions on Sleep Quality and Insomnia in Perimenopausal and Postmenopausal Women: A Meta-Analysis

This study aimed to analyze the effects of nonpharmacological interventions on perimenopausal and postmenopausal women with sleep problems. Eight databases (MEDLINE/PubMed, Cochrane Library, EMBASE, CINAHL, and four Korean databases) were searched, from their inception through to 30 November 2021, for randomized controlled trials (RCTs) evaluating the effects of nonpharmacological interventions versus control conditions on sleep quality and insomnia in perimenopausal and postmenopausal women. Sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI), and the severity of insomnia was assessed using the Insomnia Severity Index (ISI). In the meta-analysis, corrected standardized mean differences (SMDs; Hedges' g) and 95% confidence intervals (CIs) were calculated as effect measures by applying the random effects model and inverse variant method. Fifteen trials met our inclusion criteria. Nonpharmacological interventions were found to have positive effects on sleep quality, measured with the PSQI (SMD = -1.32; 95% CI = -1.78 to -0.86; p < 0.001), and on the severity of insomnia, measured using the ISI (SMD = -1.11; 95% CI = -1.82 to -0.41; p = 0.002), compared with the control groups. Among perimenopausal and postmenopausal women with sleep problems, nonpharmacological interventions improved sleep quality and reduced the severity of insomnia.

Aromatherapy with single essential oils can significantly improve the sleep quality of cancer patients: a meta-analysis

Objective

To investigate the effect of aromatherapy on sleep quality in cancer patients.

Methods

Published literature on the effect of aromatherapy in cancer patients with sleep disorders in the form of randomized controlled trials (RCTs) were systematically retrieved and screened from PubMed, Cochrane Library, Embase, CBM, CNKI, VIP, and Wanfang databases from inception to November 2021. The methodological quality of the included studies was critically and independently evaluated by two reviewers using the Cochrane Risk of Bias Assessment Tool for RCTs. The correlated data were extracted using the pre-designed form, and all analyses were performed using Reviewer Manager version 5.4. Due to the difference in sleep quality instruments, the data extracted in this study were in the form of standard mean difference (SMD).

Results

Ten RCTs included 933 patients (experimental group: 474, control group: 459), and the risk of bias in the included studies was moderate. Aromatherapy could significantly improve the sleep quality of cancer patients [SMD = − 0.79, 95% CI (− 0.93, − 0.66), p < 0.01], especially those with breast cancer [SMD = − 0.98, 95% CI (− 1.57, − 0.40), p < 0.01]. Aromatherapy with single essential oil had a better effect on sleep quality [SMD = -0.94, 95%CI (− 1.25, − 0.62), p < 0.01], of which lavender essential oil had the best effect [SMD = -1.06,95%CI (− 1.49, − 0.63), p < 0.01] while compound essential oils had no effect on sleep quality improvement in cancer patients [SMD = -0.21, 95%CI (− 0.57, 0.14), p = 0.23]. Four of the ten RCTs reported the occurrence of adverse events, of which only one RCT indicated that patients had headache and sneezing while the remaining six did not.

Conclusions

This meta-analysis of 10 RCTs reveals that aromatherapy with single essential oil had a substantial effect on the sleep quality of cancer patients and should be recommended as a beneficial complementary therapy to promote sleep quality in cancer patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12906-022-03668-0.

A critical review on clinical evidence of the efficacy of lavender in sleep disorders

Sleep disorders are one of the most prevalent psychiatric diseases. Insomnia is the most common sleep disorder amongst the general population. It is also one of the most frequent complaints in primary healthcare centers. Lavender is called "the broom of the brain" in different oriental traditional medicines. It is one of the most used plants for patients with sleep disorders. This study reviews what is currently known about the use of lavender for sleep disorders in patients with different diseases, from cancers and end-stage renal disease to neurological-psychiatric diseases (e.g., depression, dementia, and autism), respiratory, cardiac, and metabolic diseases. Additionally, its most used administration route is the inhalation of its essential oil (i.e., aromatherapy) alone or in combination by massage. Some limitations of the reviewed literature were discussed briefly. Overall, this critical review provides promising evidence of the lavender efficacy for sleep disorders in a wide variety of populations and diseases. However, further clinical studies with robust design and longer durations of intervention are necessary for more evidence-based judgment on its effect on sleep problems and to investigate its mechanism of action.