The Different Faces of Insomnia

Sleep disturbance associated with the menopause

IMPORTANCE AND OBJECTIVES

Sleep disturbance is one of the most common and debilitating symptoms experienced by women during the menopause transition. However, there are currently no therapies specifically approved for sleep disturbance associated with the menopause. Here, we consider how to characterize sleep disturbance associated with the menopause and discuss its etiology, including the latest advances in our understanding of the neuronal circuits that regulate reproduction, body temperature, sleep, and mood; and reflect on its impact on women's health and well-being. We also examine the current treatment landscape and look to the future of treatment for this condition.

METHODS

We conducted a review of the literature and combined this with discussion with experts in the fields of sleep and menopause as well as experiences from our own clinical practices.

DISCUSSION AND CONCLUSIONS

Sleep disturbance associated with the menopause is characterized by frequent night-time awakenings and increased awake time after sleep onset. Its impacts are wide-ranging, negatively affecting health as well as personal and social relationships, productivity, and work performance. There is currently an unmet need for effective, safe, and well-tolerated treatments to address this important symptom, and wider recognition of the association between sleep disturbances and the menopause is needed. Sleep disturbances associated with the menopause can result from hormone changes as well as vasomotor and mood symptoms. Growing research has contributed to our knowledge of the role of hypothalamic estrogen-sensitive kisspeptin/neurokinin B/dynorphin neurons. These neurons are thought to integrate the gonadotropin-releasing hormone pathway and the pathways responsible for the homeostatic control of body temperature and the circadian regulation of sleep-wake cycles. Understanding these neurons offers the potential to create treatments that target a key cause of sleep disturbance associated with the menopause. Further research to understand their etiology and characterize the neuronal circuits responsible could benefit the development of these targeted treatment approaches.

Cannabidiol for moderate-severe insomnia: a randomized controlled pilot trial of 150 mg of nightly dosing

STUDY OBJECTIVES

Low-dose cannabidiol (CBD) has become readily available in numerous countries; however, little consensus exists on its efficacy as a sleep aid. This trial explored the efficacy of 150 mg of CBD (n = 15) compared with placebo (n = 15) as a sleep aid in primary insomnia. CBD supplementation was hypothesized to decrease insomnia symptoms and improve aspects of psychological health, relative to placebo.

METHODS

Using a randomized, placebo-controlled, parallel design featuring a single-blind placebo run-in week followed by a 2-week double-blind randomized dosing phase, participants consumed the assigned treatment sublingually 60 minutes before bed nightly. Wrist-actigraphy and sleep diaries measured daily sleep. Sleep quality, sleep effort, and well-being were measured weekly over 4 in-laboratory visits. Insomnia severity and trait anxiety were measured at screening and study conclusion.

RESULTS

Insomnia severity, self-reported sleep-onset latency, sleep efficiency, and wake after sleep onset did not differ between treatments throughout the trial (all P > .05). Compared with placebo, the CBD group reported greater well-being scores throughout the trial (trial end mean difference = 2.60; standard error: 1.20), transient elevated behavior following wakefulness scores after 1 week of treatment (mean difference = 3.93; standard error: 1.53), and had superior objective sleep efficiency after 2 weeks of treatment (mean difference = 6.85; standard error: 2.95) (all P < .05). No other significant treatment effects were observed.

CONCLUSIONS

Nightly supplementation of 150 mg CBD was similar to placebo regarding most sleep outcomes while sustaining greater well-being, suggesting more prominent psychological effects. Additional controlled trials examining varying treatment periods and doses are crucial.

CLINICAL TRIAL REGISTRATION

Registry: Australian New Zealand Clinical Trials Registry; Name: Cannabidiol (CBD) treatment for insomnia; URL: https://anzctr.org.au/Trial/Registration/TrialReview.aspx?ACTRN=12620000070932; Identifier: ACTRN12620000070932.

CITATION

Narayan AJ, Downey LA, Rose S, Di Natale L, Hayley AC. Cannabidiol for moderate-severe insomnia: a randomized controlled pilot trial of 150 mg of nightly dosing. J Clin Sleep Med. 2024;20(5):753-763.

Fine tuned personalized machine learning models to detect insomnia risk based on data from a smart bed platform

Introduction

Insomnia causes serious adverse health effects and is estimated to affect 10-30% of the worldwide population. This study leverages personalized fine-tuned machine learning algorithms to detect insomnia risk based on questionnaire and longitudinal objective sleep data collected by a smart bed platform.

Methods

Users of the Sleep Number smart bed were invited to participate in an IRB approved study which required them to respond to four questionnaires (which included the Insomnia Severity Index; ISI) administered 6 weeks apart from each other in the period from November 2021 to March 2022. For 1,489 participants who completed at least 3 questionnaires, objective data (which includes sleep/wake and cardio-respiratory metrics) collected by the platform were queried for analysis. An incremental, passive-aggressive machine learning model was used to detect insomnia risk which was defined by the ISI exceeding a given threshold. Three ISI thresholds (8, 10, and 15) were considered. The incremental model is advantageous because it allows personalized fine-tuning by adding individual training data to a generic model.

Results

The generic model, without personalizing, resulted in an area under the receiving-operating curve (AUC) of about 0.5 for each ISI threshold. The personalized fine-tuning with the data of just five sleep sessions from the individual for whom the model is being personalized resulted in AUCs exceeding 0.8 for all ISI thresholds. Interestingly, no further AUC enhancements resulted by adding personalized data exceeding ten sessions.

Discussion

These are encouraging results motivating further investigation into the application of personalized fine tuning machine learning to detect insomnia risk based on longitudinal sleep data and the extension of this paradigm to sleep medicine.

Nocturnal positive pressure ventilation improves relationship satisfaction of patients with OSA and their partners

OBJECTIVE

Continuous positive airway pressure (CPAP) ventilation is considered the therapeutic standard for obstructed sleep apnea (OSA). Therapy success may also be affected by the patient's bed partner. A questionnaire was developed and tested that measures the attitude of the bed partner towards CPAP therapy and relationship effects.

METHODS

A new questionnaire to capture bed partners' attitude towards CPAP mask therapy was used with an anonymous sample of 508 bed partners. Possible constructs underlying the attitude of the bed partner towards mask appearance have been investigated by means of a Principal Components Analysis.

RESULTS

The survey revealed bed partners' positive attitude towards their partner's CPAP therapy (over 90% of bed partners were happy with the therapy, over 75% would recommend the therapy). Importantly, the bed partners' satisfaction with the relationship increased significantly during CPAP therapy (before therapy: 49% were satisfied, after therapy initiation: 70%; p<.001). There was a strong correlation between support for CPAP therapy and improved sleep quality of bed partners (r = 0.352, p>.001). Furthermore, the validation of the questionnaire through principal components analysis revealed three major factors: Attitude (of the bed partner towards CPAP therapy), Looks (of the mask perceived by the bed partner), Intimacy (effect of CPAP therapy on relationship and intimacy).

CONCLUSION

Both, the OSA patient and the bed partner benefit from CPAP therapy. This is the first bed partner questionnaire - interviewing the bed partner alone and anonymously - that showed that CPAP therapy also positively influences the relationship. We recommend that the bed partner be involved in the CPAP treatment from the start of therapy.

Impact of Gender on Insomnia

There is a distinct preponderance of female insomniacs when compared to male insomniacs. The aim of this study was to examine possible gender differences in the causes for insomnia, and the phenotypes of insomnia, and to investigate whether gender-specific insomnia diagnosis and treatment could be relevant in clinical practice. Data were collected from 121 insomniac patients by a medical specialist in the framework of normal clinical practice in Germany. The data consist of the patient’s medical history and various sleep-related patient questionnaires. Data from both genders were tested for independence using chi-square tests and Mann–Whitney U tests. We found a correlation between the gender of the patient and insomnia phenotypes in several aspects: concomitant lipometabolic disorders, diabetes mellitus, and high BMIs are more common in male insomniacs (p < 0.05). Frequency of insomnia occurrence in certain age groups, insomnia severity, distribution of SOI (sleep onset insomnia), SMI (sleep maintenance insomnia) and combined SOI + SMI, sleep duration, the time needed to seek medical consultation, trying out sleep-inducing drugs/techniques and the trigger, etiology and familial predisposition of the insomniac disorder were independent of the patient’s gender. We would like to re-evaluate the results with a larger number of patients in a further study.

Association between exposure to light at night (LAN) and sleep problems: A systematic review and meta-analysis of observational studies

BACKGROUND

Accumulating evidence have investigated the effects of nighttime light exposure on sleep problems. Nevertheless, the evidence of the relationship between light at night (LAN) and sleep problems remains scarce and inconsistent.

OBJECTIVE

Conducted a systematic review and meta-analysis based on observational studies to examine the association between LAN exposure and sleep problems among human subjects.

METHODS

We systematically searched three databases (PubMed, Web of Science, and Embase) to identify potentially eligible studies through May 25, 2022. The risk of bias and the quality of the generated evidence were assessed by two authors using the National Toxicology Program's Office of Health Assessment and Translation (OHAT) risk of bias rating tool and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) guideline. Random-effects model was applied to synthesize the risk estimates across eligible studies. The heterogeneity of included studies was quantified by the statistics of I².

RESULTS

A total of 7 cross-sectional studies comprising 577,932 participants were included. Individuals with higher levels of LAN exposure were associated with a 22 % (Summary Odds Ratio, SOR: 1.22, 95 %CI: 1.13-1.33) increased prevalence of sleep problems. The pooled effect size of indoor LAN exposure (SOR: 1.74, 95%CI: 1.27-2.37) associated with sleep problems was significantly higher than outdoor LAN exposure (SOR: 1.19, 95%CI: 1.11-1.29; P = 0.022). Additionally, dose-response analysis demonstrated that LAN intensity threshold exceeding 5.8 nW/cm²/sr (SOR: 1.04, 95%CI: 1.01-1.07) had a significant effect on sleep problems and the prevalence of sleep problems was increasing with increase in LAN intensity.

CONCLUSIONS

Overall, our findings support the detrimental effects of LAN exposure on sleep. Maintaining bedroom darkness at night may be a feasible measure to reduce the prevalence of sleep problems. Future longitudinal studies with more advanced LAN assessment methods are required to move the field forward.

Sleep Continuity, Stability and Cyclic Organization Are Impaired in Insomniacs: A Case-Control Study

The possibility of distinguishing insomniacs from good sleepers based on polysomnography (PSG) remains an open question. While these groups show modest differences in traditional PSG parameters, some studies suggest that finer measures may be more useful. Here we assess differences between good sleepers (GS), poor sleepers (PS) and insomniacs (IN) in classical PSG measures as well as in sleep continuity, stability and cyclic organization. PSG-monitored sleep (two nights) of 17 IN (diagnosed through a standard clinical interview; Pittsburgh Sleep Quality Index (PSQI) ≥ 5, Insomnia Severity Index (ISI) > 14) was compared to that of 33 GS (PSQI < 5) and 20 PS (PSQI ≥ 5, ISI ≤ 14). Compared to GS, IN were impaired in sleep macrostructure (sleep latency, sleep efficiency, WASO%) and in continuity, stability and organization, whereas PS only showed disrupted continuity and stability. Spindle parameters were comparable between IN and GS, but the former displayed enhanced power in fast frequency bands. Our findings support the hypothesis of a continuum between individuals with self-reported poor sleep and insomniacs. Further, they add to extant data on impaired sleep continuity, stability and organization in poor sleepers and elderly individuals, underlining the utility of including these measures in standard sleep assessments.

Night shifts, insomnia, anxiety, and depression among Chinese nurses during the COVID-19 pandemic remission period: A network approach

Background

The outbreak of the COVID-19 pandemic imposed a heavy workload on nurses with more frequent night shifts, which led to higher levels of insomnia, depression, and anxiety among nurses. The study aimed to describe the symptom-symptom interaction of depression, anxiety, and insomnia among nurses and to evaluate the impact of night shifts on mental distress via a network model.

Methods

We recruited 4,188 nurses from six hospitals in December 2020. We used the Insomnia Severity Index, Patient Health Questionnaire-9, and Generalized Anxiety Disorder Scale-7 to assess insomnia, depression, and anxiety, respectively. We used the gaussian graphical model to estimate the network. Index expected influence and bridge expected influence was adapted to identify the central and bridge symptoms within the network. We assessed the impact of night shifts on mental distress and compared the network structure based on COVID-19 frontline experience.

Results

The prevalence of depression, anxiety, and insomnia was 59, 46, and 55%, respectively. Nurses with night shifts were at a higher risk for the three mental disorders. "Sleep maintenance" was the central symptom. "Fatigue," "Motor," "Restlessness," and "Feeling afraid" were bridge symptoms. Night shifts were strongly associated with sleep onset trouble. COVID-19 frontline experience did not affect the network structure.

Conclusion

"Sleep maintenance," "Fatigue," "Motor," and "Restlessness" were important in maintaining the symptom network of anxiety, depression, and insomnia in nurses. Further interventions should prioritize these symptoms.

Bidirektionale Aspekte von SARS-CoV-2 und Schlafstörungen

Im vorliegenden Überblick wird der Zusammenhang zwischen der Schlaflänge, der Schlafqualität, dem Immunsystem und einer SARS-CoV-2-Infektion aufgezeigt. Kurzer und/oder schlechter Schlaf kann einen Einfluss auf das Entstehen einer Infektion sowie deren Verlauf haben. Ebenso können eine SARS-CoV-2-Infektion sowie die pandemiebedingten Umstände den Schlaf negativ beeinflussen. Dabei nimmt insbesondere die Schlafqualität ab. Die Pandemie hat somit das Potenzial, Schlafstörungen auszulösen, zu verstärken und/oder aufrechtzuerhalten. Diese Befunde haben insofern Relevanz, als nur ein ausreichender und erholsamer Schlaf das Immunsystem stärkt und protektiv bezüglich einer Infektion und ihres Verlaufs wirken kann. Die Pandemie stellt somit eine weitere Herausforderung für die Schlafmedizin dar und bietet gleichzeitig die Chance, die Bedeutung des Schlafs für die Gesundheit und den Krankheitsverlauf zu vermitteln.

The top 100 most cited papers in insomnia: A bibliometric analysis

OBJECTIVE

The number of citations to a paper represents the weight of that work in a particular area of interest. Several highly cited papers are listed in the bibliometric analysis. This study aimed to identify and analyze the 100 most cited papers in insomnia research that might appeal to researchers and clinicians.

METHODS

We reviewed the Web of Science (WOS) Core Collection database to identify articles from 1985 to 24 March 2022. The R bibliometric package was used to further analyze citation counts, authors, year of publication, source journal, geographical origin, subject, article type, and level of evidence. Word co-occurrence in 100 articles was visualized using VOS viewer software.

RESULTS

A total of 44,654 manuscripts were searched on the Web of Science. Between 2001 and 2021, the top 100 influential manuscripts were published, with a total citation frequency of 38,463. The top countries and institutions contributing to the field were the U.S. and Duke University. Morin C.M. was the most productive author, ranking first in citations. Sleep had the highest number of manuscripts published in the top 100 (n = 31), followed by Sleep Medicine Reviews (n = 9). The most cited manuscript (Bastien et al., Sleep Medicine, 2001; 3,384 citations) reported clinical validation of the Insomnia Severity Index (ISI) as a brief screening indicator for insomnia and as an outcome indicator for treatment studies. Co-occurrence analyses suggest that psychiatric disorders combined with insomnia and cognitive behavioral therapy remain future research trends.

CONCLUSION

This study provides a detailed list of the most cited articles on insomnia. The analysis provides researchers and clinicians with a detailed overview of the most cited papers on insomnia over the past two decades. Notably, COVID-19, anxiety, depression, CBT, and sleep microstructure are potential areas of focus for future research.