The exploratory power of sleep effort, dysfunctional beliefs and arousal for insomnia severity and polysomnography-determined sleep

The Role of Sleep Effort as a Mediator Between Anxiety and Depression

Depression, anxiety, and insomnia are all conditions that share a complex bidirectional relationship. Sleep effort is a construct with cognitive and behavioral components that perpetuates insomnia. Although many studies have examined the associations between these three variables, no studies have yet examined sleep effort as a mediating variable between anxiety and depression and vice versa. Online versions of the Hospital Anxiety and Depression Scale and the Glasgow Sleep Effort Scale were administered to a sample of 1927 higher education students aged 18-40 years (75.9% women and 76% from 18 to 23 years old). As part of the survey, participants also completed a sociodemographic questionnaire. Mediation analysis indicated that sleep effort mediates the relationship between depression and anxiety, when the former was the predictor and the latter was the criterion. Moreover, sleep effort also mediated the relationship between anxiety and depression when the former was the predictor and the latter was the criterion, albeit in a lesser extent. Sleep effort appears to play a bidirectional mediational role between depression and anxiety, being a potential target for intervention.

Assessing non-dysfunctional attitudes toward sleep: psychometric properties of the Charlotte Attitudes Toward Sleep scale in Portuguese samples

OBJECTIVES

To adapt the Charlotte Attitudes Toward Sleep (CATS) scale, the only self-assessment instrument measuring non-dysfunctional attitudes toward sleep, into Portuguese and to study its psychometric properties in a Portuguese sample.

METHOD

A sample of 1858 participants, recruited through non-probabilistic methods, was randomly split in two subsamples; one was used to develop the CATS model, the other for testing model invariance. We used structural equation models to assess factorial validity, measurement invariance, and relationships with other variables (e.g., the Karolinska Sleep Questionnaire) through confirmatory factorial analysis and causal models using a robust maximum likelihood method with Satorra-Bentler correction.

RESULTS

The CATS factorial model showed excellent evidence of factorial validity (robust CFI = 0.987, TLI = 0.979, SRMR = 0.026, RMSEA = 0.043), good reliability indicators (α and ώ1 > 0.75), and strict invariance of measurement (|∆CFI|< 0.01). CATS factors were weak-to-moderate predictors of sleep behaviors (β < 0.4). The scale showed evidence of divergent validity with the Karolinska Sleep Questionnaire. Some items had significant sensitivity problems and/or did not have adequate factorial weights and had to be dropped from the model.

CONCLUSIONS

The CATS is a new and promising scale with solid evidence of validity in terms of internal structure, but with sensitivity issues at item level. Further work should be carried out at item level to increase sensitivity and predictive validity, and further research with other samples, such as clinical sleep medicine patients, should be conducted.

Predicting response to stepped-care cognitive behavioral therapy for insomnia using pre-treatment heart rate variability in cancer patients

OBJECTIVE

This study examined whether high frequency heart-rate variability (HF-HRV) and HF-HRV reactivity to worry moderate response to cognitive behavioural therapy for insomnia (CBT-I) within both a standard and stepped-care framework among cancer patients with comorbid insomnia. Biomarkers such as HF-HRV may predict response to CBT-I, a finding which could potentially inform patient allocation to different treatment intensities within a stepped-care framework.

METHODS

177 participants (86.3 % female; Mage = 55.3, SD = 10.4) were randomized to receive either stepped-care or standard CBT-I. 145 participants had their HRV assessed at pre-treatment during a rest and worry period. Insomnia symptoms were assessed using the Insomnia Severity Index (ISI) and daily sleep diary across five timepoints from pre-treatment to a 12-month post-treatment follow-up.

RESULTS

Resting HF-HRV was significantly associated with pre-treatment sleep efficiency and sleep onset latency but not ISI score. However, resting HF-HRV did not predict overall changes in insomnia across treatment and follow-up. Similarly, resting HF-HRV did not differentially predict changes in sleep diary parameters across standard or stepped-care groups. HRV reactivity was not related to any of the assessed outcome measures in both cross-sectional and longitudinal analyses.

CONCLUSION

Although resting HF-HRV was related to initial daily sleep parameters, HF-HRV measures did not significantly predict longitudinal responses to CBT-I. These findings suggest that HF-HRV does not predict treatment responsiveness to CBT-I interventions of different intensity in cancer patients.

Chronic insomnia, REM sleep instability and emotional dysregulation: A pathway to anxiety and depression?

The world-wide prevalence of insomnia disorder reaches up to 10% of the adult population. Women are more often afflicted than men, and insomnia disorder is a risk factor for somatic and mental illness, especially depression and anxiety disorders. Persistent hyperarousals at the cognitive, emotional, cortical and/or physiological levels are central to most theories regarding the pathophysiology of insomnia. Of the defining features of insomnia disorder, the discrepancy between minor objective polysomnographic alterations of sleep continuity and substantive subjective impairment in insomnia disorder remains enigmatic. Microstructural alterations, especially in rapid eye movement sleep ("rapid eye movement sleep instability"), might explain this mismatch between subjective and objective findings. As rapid eye movement sleep represents the most highly aroused brain state during sleep, it might be particularly prone to fragmentation in individuals with persistent hyperarousal. In consequence, mentation during rapid eye movement sleep may be toned more as conscious-like wake experience, reflecting pre-sleep concerns. It is suggested that this instability of rapid eye movement sleep is involved in the mismatch between subjective and objective measures of sleep in insomnia disorder. Furthermore, as rapid eye movement sleep has been linked in previous works to emotional processing, rapid eye movement sleep instability could play a central role in the close association between insomnia and depressive and anxiety disorders.

Sleep effort and its measurement: A scoping review

Insomnia disorder is characterized by disruption in sleep continuity and an overall dissatisfaction with sleep. A relevant feature of insomnia is sleep effort, which refers to both cognitive and behavioural conscious attempts to initiate sleep. The Glasgow Sleep Effort Scale is a self-report tool developed to assess this construct. The objective of the current scoping review was to map how sleep effort has been discussed in the literature and operationalized through its respective measure. Medline/PubMed, Scopus, Web of Science and PsycInfo databases were used to search for potential studies. The search query used in databases was the specific name of the self-reported tool itself (Glasgow Sleep Effort Scale) and "sleep effort" term. This scoping review followed JBI guidelines. To be included, records pertaining to any type of study that mentioned the Glasgow Sleep Effort Scale were considered. No language constraint was used. At the end, 166 initial records were retrieved. From those, 46 records met eligibility criteria and were analysed. Among the main findings, it was observed that the Glasgow Sleep Effort Scale has been increasingly used in recent years, with a notable observed upward trend, especially in the last 2 years. In addition to the original measure, only three published adapted versions of the instrument were identified. This suggests that there is limited research on adapting the scale for different populations or contexts. Sleep effort has been increasingly studied in the last few years. Nonetheless, more research on the Glasgow Sleep Effort Scale tool is recommended, including cross-cultural adaptations.

Changes in sleep effort mediate insomnia severity in older adults following online cognitive behavioural therapy

BACKGROUND

To examine treatment mechanisms of digitally delivered cognitive behavioural therapy for insomnia (CBT-I), this study assessed the mediating effects of dysfunctional beliefs, hyperarousal, locus of control, self-efficacy, sleep effort, and safety behaviours on self-reported insomnia severity in older adults before and following the completion of a self-guided, online CBT-I program.

METHODS

The baseline and follow-up measurements were completed by 62 older adults (55 female, 89%). This was a two-condition within-participant design. Mediation analysis using a parallel mediation model was conducted using the MEMORE macro for repeated measure designs.

RESULTS

Out of all the included mediator variables, only a reduction in sleep effort scores (0.88; SE 0.51; 95% CI 0.001-2.00) significantly mediated changes in insomnia severity scores following the intervention. Insomnia severity scores significantly reduced following the intervention (Mpre  = 9.84, SD = 5.89, Mpost  = 6.87, SD = 4.90); t(61) = 5.19, P = <0.001; d = 0.55 95% CI 0.38-0.93.

CONCLUSIONS

Sleep in older adults improved following digitally delivered CBT-I, and these changes were influenced by a reduction in sleep control efforts exerted by participants. These findings highlight possible treatment pathways of CBT-I. Further investigation of CBT-I as a strategy to prevent sleep problems is warranted.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry (ANZCTR), ACTRN 12619001509156; http://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=378451.

Neurophysiological Parameters Influencing Sleep-Wake Discrepancy in Insomnia Disorder: A Preliminary Analysis on Alpha Rhythm during Sleep Onset

Sleep state misperception (SSM) is a common issue in insomnia disorder (ID), causing a discrepancy between objective and subjective sleep/wake time estimation and increased daytime impairments. In this context, the hyperarousal theory assumes that sustained central nervous system activation contributes to the SSM. This study investigates factors influencing SSM during sleep latency (SL) and total sleep time (TST). Objective polysomnographic sleep variables (the alpha density index, latency-to-sleep stages and the first K-complex, and Rapid Eye Movement (REM) arousal density) and subjective sleep indices, taken from sleep diaries, were analyzed in 16 ID patients. Correlation analyses revealed a positive association between the degree of SL misperception (SLm) and the percentage of epochs that contained a visually scored stereotyped alpha rhythm during objective SL. A regression analysis showed that the REM arousal density and alpha density index significantly predicted TST misperception (TSTm). Furthermore, the degree of SLm was associated with an increased probability of transitioning from stage 1 of non-REM sleep to wakefulness during subjective SL. These findings support the role of hyperarousal in SSM and highlight the importance of alpha activity in unravelling the heterogeneous underpinnings of SSM.

Revisiting the Psychobiological Inhibition Model: a conceptual framework for understanding and treating insomnia using cognitive and behavioural therapeutics (CBTx)

Sleep is a biological imperative, so one might wonder "what has psychology got to do with it?" A person's behaviours, thoughts, emotions and interactions with the environment inevitably serve for good, or for ill, as the "setting conditions" for the expression of sleep. Put simply, although sleep is not a psychological phenomenon, sleep has crucial behavioural dependencies. Consequently, the Psychobiological Inhibition Model can embrace numerous, potentially interacting, pathways to the persistence of this ubiquitous disorder, providing an overarching conceptual framework for why and how insomnia develops. The clinical guideline treatment for chronic insomnia is cognitive behavioural therapy. Although typically delivered as "talking therapy", cognitive behavioural therapy is not some form of "psychobabble". Rather, the Psychobiological Inhibition Model framework for insomnia articulates how specific techniques can correct the various ways in which the expression of normal sleep and circadian brain-behaviour relationships have become disrupted. Indeed, cognitive behavioural therapy is best conceived of as an approach to treatment rather than being one specific agent. A shift in emphasis towards a cognitive and behavioural therapeutics formulary would provide improved impetus to understanding of how insomnia develops, and of how it may best be treated in any given patient.

Hyperarousal in insomnia disorder: Current evidence and potential mechanisms

Insomnia disorder is among the most frequent mental disorders, making research on its aetiology and pathophysiology particularly important. A unifying element of many aetiological and pathophysiological models is that they support or even centre on the role of some form of hyperarousal. In this theoretical review, we aim to summarise the current evidence on hyperarousal in insomnia. Hyperarousal is discussed as a state of relatively increased arousal in physiological, cortical and cognitive-emotional domains. Regarding physiological hyperarousal, there is no conclusive evidence for the involvement of autonomous variables such as heart rate and heart rate variability, whereas recent evidence points to a pathophysiological role of neuroendocrine variables. In addition, current literature supports a central involvement of cortical arousal, that is, high-frequency electroencephalographic activity. An increasingly important focus in the literature is on the role of other microstructural sleep parameters, especially the existence of microarousals during sleep. Beyond that, a broad range of evidence exists supporting the role of cognitive-emotional hyperarousal in the form of insomnia-related thought and worries, and their concomitant emotional symptoms. Besides being a state marker of insomnia, hyperarousal is considered crucial for the predisposition to insomnia and for the development of comorbid mental disorders. Thus, beyond presenting evidence from cross-sectional studies on markers of hyperarousal in insomnia, hypotheses about the mechanisms of hyperarousal are presented. Nevertheless, longitudinal studies are needed to further elucidate the mechanism of hyperarousal throughout the course of the disorder, and future studies should also focus on similarities and differences in hyperarousal across different diagnostic entities.

The potential of biomarkers for diagnosing insomnia: Consensus statement of the WFSBP Task Force on Sleep Disorders

OBJECTIVES

Thus far, the diagnosis of insomnia is based on purely clinical criteria. Although a broad range of altered physiological parameters has been identified in insomniacs, the evidence to establish their diagnostic usefulness is very limited. Purpose of this WFSBP Task Force consensus paper is to systematically evaluate a series of biomarkers as potential diagnostic tools for insomnia.

METHODS

A newly created grading system was used for assessing the validity of various measurements in establishing the diagnosis of insomnia; these measurements originated from relevant studies selected and reviewed by experts.

RESULTS

The measurements with the highest diagnostic performance were those derived from psychometric instruments. Biological measurements which emerged as potentially useful diagnostic instruments were polysomnography-derived cyclic alternating pattern, actigraphy, and BDNF levels, followed by heart rate around sleep onset, deficient melatonin rhythm, and certain neuroimaging patterns (mainly for the activity of frontal and pre-frontal cortex, hippocampus and basal ganglia); yet, these findings need replication, as well as establishment of commonly accepted methodology and diagnostic cut-off points. Routine polysomnography, EEG spectral analysis, heart rate variability, skin conductance, thermoregulation, oxygen consumption, HPA axis, and inflammation indices were not shown to be of satisfactory diagnostic value.

CONCLUSIONS

Apart from psychometric instruments which are confirmed to be the gold standard in diagnosing insomnia, six biomarkers emerge as being potentially useful for this purpose.

The Effects of Cognitive Behavioral Therapy for Insomnia on Multidimensional Perfectionism

Perfectionism is related to insomnia and objective markers of disturbed sleep. This study examined whether multidimensional perfectionism is related to dysfunctional beliefs about sleep, sleep-effort, pre-sleep arousal, and polysomnography-determined markers of sleep among individuals with insomnia. The effects of cognitive behavioral therapy for insomnia (CBT-I) on perfectionism was also examined. This was a secondary analysis of a randomized controlled trial on CBT-I. Forty-three insomnia patients were randomized to treatment (receiving CBT-I) or waitlist control groups. Sleep was recorded using polysomnography at baseline. Participants completed measures of perfectionism, dysfunctional beliefs about sleep, sleep-effort and pre-sleep arousal at baseline and posttreatment. Total perfectionism scores and doubts about action, concern over mistakes and personal standards were each significantly related to increased sleep effort, pre-sleep arousal and dysfunctional beliefs about sleep at baseline. Patients receiving treatment displayed increased total perfectionism scores posttreatment d = .49. In those receiving treatment, levels of organization d = .49 and parental expectations d = .47 were significantly increased posttreatment, relative to baseline. In line with the literature, our results confirm that perfectionism is related to insomnia. Here, insomnia was related to increased sleep effort, pre-sleep arousal and dysfunctional beliefs about sleep. The propensity to maintain a high standard of order and organization may be elevated following CBT-I, considering the treatment protocol expects patients to strictly adhere to a set of clearly defined rules. Levels of parental expectations may be increased following CBT-I since the patient-therapist-relationship may trigger implicit expectations in patients which are reminiscent of their relationship to their parents.

On the relationship between EEG spectral analysis and pre-sleep cognitive arousal in insomnia disorder: towards an integrated model of cognitive and cortical arousal

According to the hyperarousal model, insomnia is characterised by increased arousal in the cortical, cognitive, and physiological domains. However, the interaction between these arousal domains is poorly understood. The present observational case-control study aimed to investigate cortical arousal during the night, pre-sleep cognitive arousal and the relationship between these two domains. A total of 109 patients with insomnia disorder (ID) and 109 age-and gender matched healthy controls were investigated on two sleep laboratory nights. Electroencephalographic (EEG) spectral power during non-rapid eye movement (NREM) and REM sleep was analysed as a measure of cortical arousal. In addition, patients completed the Pre-Sleep Arousal Scale (PSAS), which consists of two subscales, one for cognitive arousal (PSAS-CA) and one for self-reported somatic arousal (PSAS-SA). The relationship between the subscale scores and EEG spectral power was calculated by multi- and univariate analyses of variance. During NREM and REM sleep, patients with ID showed significantly increased spectral power in the EEG gamma band. In addition, patients with ID showed significantly increased scores on both subscales of the PSAS. The PSAS-CA score was significantly associated with increased NREM and REM gamma power, whereas PSAS-SA was associated with decreases in NREM and REM gamma power. Consistent with our hypothesis, patients with ID showed increased cortical and cognitive arousal. Moreover, there was an association between these two arousal domains, which may indicate that cortical arousal during the night is (at least in part) elicited by pre-sleep worry and rumination.

The Role of Dysfunctional Sleep Beliefs in Mediating the Outcomes of Web-Based Cognitive Behavioral Therapy for Insomnia in Community-Dwelling Older Adults: Protocol for a Single-Group, Nonrandomized Trial

BACKGROUND

Sleeping well is an essential part of good health. Older adult populations report a high rate of sleep problems, with recent studies suggesting that cognitive processes as well as behavioral and hyperarousal-related mechanisms could be important factors in the development and maintenance of insomnia. Individuals who have an asynchronous or uncoupled sleep pattern and sleep appraisal-those who complain about their sleep but do not have poor sleep quality, and vice versa-might show differences in subjective sleep and sleep perceptions and other characteristics that could impact their treatment outcomes following cognitive behavioral therapy for insomnia (CBT-I).

OBJECTIVE

The purpose of this protocol is to describe the rationale and methods for a nonrandomized, single-arm trial assessing objective and subjective sleep quality in community-dwelling older adults aged 60-80 years with synchronous sleep patterns and sleep appraisal compared to those in older adults with asynchronous sleep patterns and sleep appraisal. The trial will further examine the role of cognitive, behavioral, and hyperarousal processes in mediating the treatment outcomes of web-based CBT-I.

METHODS

This trial aims to recruit a sample of 60 participants, who will be assigned to 1 of 4 sleep groups based on their sleep pattern and sleep appraisal status: complaining good sleepers, complaining poor sleepers, noncomplaining good sleepers, and noncomplaining poor sleepers, respectively. The trial will be completed in 2 phases: phase 1 will assess objective sleep (measured via wrist actigraphy) and subjective (self-reported) sleep. Phase 2 will investigate the impact of a web-based CBT-I program on the sleep outcomes of individuals with uncoupled sleep compared to that of individuals without uncoupled sleep, as well as the mediators of CBT-I.

RESULTS

Recruitment began in March 2020, and the last participants were recruited by March 2021. A total of 65 participants completed phases 1 and 2. Data analysis for phase 1 was finished in December 2021, and data analysis for phase 2 was finalized in July 2022. The results for phase 1 were submitted for publication in March 2022, and those for phase 2 will be submitted by the end of December 2022.

CONCLUSIONS

This trial will provide guidance on factors that contribute to the variability of sleep in older adults and their sleep outcomes following CBT-I. The outcomes of this study could be valuable for future research attempting to tailor CBT-I to individual needs.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry ACTRN12619001509156; https://tinyurl.com/69hhdu2w.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/32705.

A randomized, double-blind, placebo-controlled trial investigating the effects of an Ocimum tenuiflorum (Holy Basil) extract (HolixerTM) on stress, mood, and sleep in adults experiencing stress

Background

In Ayurveda, Ocimum tenuiflorum (Holy Basil) is referred to as “the elixir of life” and is believed to promote longevity and general wellbeing. Although limited, there are clinical trials to suggest Ocimum tenuiflorum has anti-stress effects.

Purpose

Examine the effects of a standardized Ocimum tenuiflorum extract (Holixer^TM) on subjective and objective measures of stress and sleep quality in adults experiencing stress.

Study design

Two-arm, parallel-group, 8-week, randomized, double-blind, placebo-controlled trial. Australian and New Zealand Clinical Trials Registry trial registration number ACTRN12621000609853.

Methods

One hundred volunteers aged 18–65 years received either 125 mg of Ocimum tenuiflorum twice daily or a placebo. Outcome measures included the Perceived Stress Scale (PSS) (primary outcome measure), Profile of Mood States, Athens Insomnia Scale (AIS), Restorative Sleep Questionnaire, and the Patient-Reported Outcomes Measurement Information System-29. Sleep quality was also assessed using a wrist-worn sleep tracker (Fitbit), and stress changes were examined by measuring between-group differences in hair cortisol and stress responses after exposure to an experiment stress procedure known as the Maastricht Acute Stress Test (MAST).

Results

Compared to the placebo, Ocimum tenuiflorum supplementation was associated with greater improvements in PSS (p = 0.003) and AIS (p = 0.025) scores; and at week 8, concentrations in hair cortisol were also lower (p = 0.025). Moreover, Ocimum tenuiflorum supplementation was associated with a buffered stress responses after exposure to the MAST as demonstrated by significantly lower concentrations in salivary cortisol (p = 0.001), salivary amylase (p = 0.001), systolic (p = 0.010) and diastolic (p = 0.025) blood pressure, and subjective stress ratings (p < 0.001). Ocimum tenuiflorum supplementation was well-tolerated with no reports of major adverse effects.

Conclusion

The results from this trial suggest that 8 weeks of supplementation with an Ocimum tenuiflorum extract (Holixer^TM) may reduce objective and subjective measures of stress, and improve subjective measures of sleep quality. However, further research using gold-standard objective sleep measures will be required to substantiate the sleep-related findings.

Clinical trial registration

https://www.anzctr.org.au/ACTRN12621000609853p.aspx, identifier: ACTRN12621000609853p.

Validity and reliability of the Turkish version of the Glasgow Sleep Effort Scale

OBJECTIVE

We aimed to assess the validity and reliability of a Turkish adaptation of the Glasgow Sleep Effort Scale (GSES).

METHODS

We randomly divided the data into two: one set (n = 374) was used for exploratory factor analysis (EFA) and the other (n = 373) for confirmatory factor analysis (CFA). The psychometric properties were assessed using the item response theory approach. Reliability analyses were assessed. Convergent validity of the GSES with the Dysfunctional Beliefs and Attitudes About Sleep Scale-16 (DBAS-16), Pittsburgh Sleep Quality Index (PSQI), Insomnia Severity Index (ISI), and Depression Anxiety Stress Scale-21 (DASS-21) were explored. For the predictive validity, we used an independent-samples t-test for comparing the total score of the GSES between poor sleepers and good sleepers following the PSQI, and between clinical insomnia and non-clinical insomnia groups according to the ISI. The cut-off score of the GSES was examined.

RESULTS

A single factor structure explaining 49.2% of the total variance was detected using the EFA. The CFA also found single-factor good fit indices. Cronbach's alpha and omega values were 0.82 and 0.83, respectively. There were statistically significant correlations between the GSES and DBAS-16, ISI, PSQI, and DASS-21 in convergent validity. In the Graded Response Model, the GSES was more efficient and provided reasonable information at the -0.75 to 2.25 theta level. The GSES cut-off score was 6 points for clinical insomnia and 3 points for poor sleepers.

CONCLUSIONS

The GSES is valid and reliable for measuring sleep effort among Turkish university students.

Pre-sleep arousal and sleep quality during the COVID-19 lockdown in Italy

Objective

The COVID-19 pandemic has strongly affected daily habits and psychological wellbeing, and many studies point to large modifications in several sleep and sleep-related domains. Nevertheless, pre-sleep arousal during the pandemic has been substantially overlooked. Since hyperarousal represents one of the main factors for the development and the perpetuation of chronic insomnia disorder, the assessment of variables associated with high levels of pre-sleep arousal during the pandemic is clinically relevant. The study aimed to assess the prevalence and predictors of perceived sleep quality and pre-sleep arousal in an Italian sample during the COVID-19 lockdown.

Methods

We used an online survey to collect self-reported sociodemographic, environmental, clinical, sleep, and sleep-related data. Our final sample included 761 participants.

Results

Beyond a high frequency of poor sleep quality, depressive and stress symptoms, our results show that almost half of the sample suffered from clinically relevant levels of at least one component (ie, cognitive, somatic) of pre-sleep arousal. Subjects with greater pre-sleep arousal exhibited poorer sleep quality. Also, sleep quality was strongly associated with somatic and cognitive pre-sleep arousal. Regarding the predictors of sleep and sleep-related measures, depressive and event-related stress symptoms were the main factors associated with both poor sleep quality and pre-sleep arousal components. Moreover, specific sociodemographic and environmental variables were uniquely related to sleep quality, cognitive or somatic pre-sleep arousal.

Conclusions

These findings suggest that the assessment of specific sleep-related factors (ie, pre-sleep arousal), together with more global measures of sleep quality, may be crucial to depict the complex impact of the pandemic on sleep, and to help prevent and counteract the spread of insomnia symptoms.

Attitudes Towards Sleep as a Time Commitment are Associated with Sleep Regularity

Objective: Irregular sleep-wake patterns are associated with poor health outcomes. However, factors that lead individuals to adopt more regular sleep-wake patterns are not well understood. This study aimed to (i) examine the relationship between sleep regularity and attitudes toward sleep in undergraduates; (ii) test an intervention to improve sleep regularity based on personalized feedback; and (iii) investigate whether changes in attitudes toward sleep associate with improved sleep regularity.Methods: Sleep-wake timing of 45 students (19.7 ± 1.8 years) was monitored daily over two weeks using an app-based diary. The least regular sleepers, calculated using the Sleep Regularity Index (SRI ≤ 81.4; N = 22), completed a four-week randomized control intervention (RCI) designed to improve sleep regularity. The Charlotte Attitudes Toward Sleep (CATS) scale was administered at baseline and post-RCI, with subscales measuring attitudes toward sleep as a time commitment (Time), and as a beneficial/enjoyable behavior (Benefits).Results: CATS Time was positively associated with SRI at baseline (r² = 0.16, p =.006) and during the four-week RCI (r² = 0.29, p =.01). CATS Benefits was not associated with SRI but was associated with sleep quality. There was no significant improvement in SRI during the intervention. The relationship between change in CATS Time and change in SRI (baseline vs. RCI) differed between intervention and control groups (r² = 0.27, p =.03).Conclusions: Attitudes toward sleep as a time commitment are associated with sleep regularity and should be considered as a target in future interventions aiming to improve sleep regularity.

The Hypersomnia Severity Index: reliability, construct and criterion validity in a clinical sample with sleep disorders

STUDY OBJECTIVES

The Hypersomnia Severity Index (HSI) was designed to assess severity and impairment of hypersomnolence and validated in persons with psychiatric disorders. Little is known about its psychometric properties in clinical samples with sleep disorders.

METHODS

158 patients (44.1±16.4 years old, 29.1% male, 19.6% racial/ethnic minority) evaluated at the Behavioral Sleep Medicine program of Penn State Health Sleep Research & Treatment Center completed the HSI and other patient-reported outcomes. We examined the HSI's reliability and factorial, construct and criterion validity.

RESULTS

The HSI showed satisfactory internal consistency (α=0.79). A two-factor structure, reflecting symptoms (HSI-S) and impairment (HSI-I), explained 56.2% of the variance. Convergent validity with Epworth Sleepiness Scale (ESS) was optimal (r=0.65) but greater for HSI-S (r=0.69) than HSI-I (r=0.39). Divergent validity was optimal for HSI-S against unrelated measures of sleep effort, reactivity and incompatible behaviors (r≤0.02). Construct validity showed higher scores in subjects with central disorders of hypersomnolence (CDH) and lower scores in subjects with chronic insomnia disorder (CID) compared to those with other sleep disorders; however, these divergent scores were primarily driven by the HSI-S rather than the HSI-I. Criterion validity showed that a HSI-S cut-off score ≥8 provided the best balance in sensitivity/specificity (0.82/0.78) to identify CDH (AUC=0.85).

CONCLUSIONS

The HSI shows satisfactory indices of reliability and validity in a clinical sample. Its construct and criterion validity are supported by its divergent association with other patient-reported outcomes and CDH vs. CID diagnoses as well as the adequate sensitivity/specificity of its HSI-S cut-off score to reliably identify CDH.

Change in Dysfunctional Sleep-Related Beliefs is Associated with Changes in Sleep and Other Health Outcomes Among Older Veterans With Insomnia: Findings From a Randomized Controlled Trial

BACKGROUND

Cognitive behavioral therapy for insomnia (CBTI) targets changing dysfunctional sleep-related beliefs. The impact of these changes on daytime functioning in older adults is unknown.

PURPOSE

We examined whether changes in sleep-related beliefs from pre- to post-CBTI predicted changes in sleep and other outcomes in older adults.

METHOD

Data included 144 older veterans with insomnia from a randomized controlled trial testing CBTI. Sleep-related beliefs were assessed with the Dysfunctional Beliefs and Attitudes about Sleep-16 (DBAS-16, subscales: Consequences, Worry/Helplessness, Sleep Expectations, Medication). Outcomes included sleep diary variables, actigraphy-measured sleep efficiency, Pittsburgh Sleep Quality Index (PSQI), Insomnia Severity Index (ISI), Epworth Sleepiness Scale (ESS), Flinders Fatigue Scale (FFS), Patient Health Questionnaire-9, and health-related quality of life. Analyses compared slope of change in DBAS subscales from baseline to posttreatment between CBTI and control, and assessed the relationship between DBAS change and the slope of change in outcomes from baseline to 6 months.

RESULTS

Compared to controls, the CBTI group demonstrated stronger associations between improvement in DBAS-Consequences and subsequent improvement in PSQI, ISI, ESS, and FFS. The CBTI group also demonstrated stronger associations between improvement in DBAS-Worry/Helplessness and subsequent improvements in PSQI, ISI, and FFS; improvements in DBAS-Medication and PSQI; and improvements in DBAS-Sleep Expectations and wake after sleep onset (sleep diary) and FFS (all p < .05).

CONCLUSIONS

Significant reduction in dysfunctional sleep-related beliefs following CBTI in older adults predicted improvement in several outcomes of sleep and daytime functioning. This suggests the importance of addressing sleep-related beliefs for sustained improvement with CBTI in older veterans.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT00781963.

Effects of work organization on the occurrence and resolution of sleep disturbances among night shift workers: a longitudinal observational study

This study aimed to investigate the association between work organization and the trajectories of insomnia patterns among night shift workers in a hospital. The health examination data of hospital workers, recorded from January 2014 to December 2018, were collected; 6765 records of 2615 night shift workers were included. Insomnia was defined as a score of ≥ 15 on the Insomnia Severity Index (ISI). Participants were categorized into five groups according to insomnia patterns derived from the analysis of their ISI scores. Work organization and socio-demographic characteristics were also investigated. Generalized estimating equation models and linear mixed models were constructed to analyze the longitudinal data. Of the total participants, 53.0% reported insomnia at least once during the follow-up period. The lack of nap opportunities and work-time control was associated with the occurrence of insomnia, whereas more than 5 years of shift work experience was related to the resolution of insomnia. All work-related factors were significantly related to insomnia risk; however, the effects were not significant in the sustained insomnia group. Although sleep problems are inevitable in night shift workers, well-designed work schedules and better work organization can help reduce the occurrence of insomnia among them.

Dysfunctional beliefs and attitudes about sleep are associated with regional homogeneity of left inferior occidental gyrus in primary insomnia patients: a preliminary resting state functional magnetic resonance imaging study

BACKGROUND

The neural mechanisms of sleep beliefs and attitudes in primary insomnia (PI) patients at resting state remain unclear. The aim of this study was to investigate the features of regional homogeneity (ReHo) in PI using resting-state functional magnetic resonance imaging (rsfMRI).

METHODS

Thirty-two PI patients and 34 normal controls (NC) underwent rsfMRI using a 3 T scanner at Tongde Hospital of Zhejiang Province. Participants were assessed with the Dysfunctional Beliefs and Attitudes about Sleep scale (DBAS-16) and Pittsburgh Sleep Quality Index (PSQI). Statistical analyses were performed to determine the regions in which ReHo differed between the two groups. Correlation analyses were performed between the ReHo index of each of these regions and DBAS-16 in PI patients.

RESULTS

PI patients showed increased ReHo values in the right superior frontal gyrus, and decreased ReHo values in the left cerebellar gyrus, left inferior occipital gyrus (IOG) and left amygdala compared with those of NC. ReHo values in the left IOG were negatively correlated with total DBAS-16 scores, and scores for "consequences of insomnia" and"worry/helplessness about sleep"in PI patients.

CONCLUSIONS

These results suggest that ReHo alterations in the left IOG may play an important role in the dysfunctional beliefs and attitudes about sleep in PI.

Are cognitive variables that maintain insomnia also involved in shift work disorder?

OBJECTIVE

Shift Work Disorder (SWD) is explained mainly by a misalignment between the sleep schedule and the circadian rhythm. However, the possible role of cognitive variables in maintaining SWD remains unknown. Therefore, the objective of this study is to evaluate whether cognitive variables known to maintain insomnia in day workers might also be involved in perpetuating SWD.

DESIGN

Cross-sectional.

SETTING

Sleep laboratory.

PARTICIPANTS

Twenty-five shift workers diagnosed with SWD (84% females; mean age = 35.9) and 22 shift workers who are good sleepers (91% females; mean age = 34.1).

MEASUREMENTS

The participants completed a sleep diary for two weeks, answered questionnaires, and underwent the Harvey's semistructured interview and the catastrophizing procedure. Data from the catastrophizing procedure underwent a content analysis.

RESULTS

Compared with good sleepers, shift workers with SWD reported experiencing more thoughts that keep them awake, more presleep cognitive arousal, more dysfunctional beliefs related to worries and helplessness, and more selective attention toward worries and noises. However, the two groups did not differ on the tendency to catastrophize about difficulties falling asleep. Furthermore, 12 catastrophizing themes were identified in the entire sample, the most frequently endorsed being "sleepiness and energy" and "performance at work."

CONCLUSIONS

The results suggest that cognitive variables may play a role in maintaining SWD. Finally, worries that interfere with sleep in shift workers are related to their work context.

Glasgow Sleep Effort Scale: Translation, Test, and Evaluation of Psychometric Properties of the Persian Version

PURPOSE

The purpose of the current study is to translate, test and evaluate the psychometric properties of the Glasgow Sleep Effort Scale (GSES) in Persian language.

METHODS

Participants consisted of two samples: a clinical sample of 120 patients (58%) with insomnia disorder meeting DSM-5 criteria for insomnia and a non-clinical sample of 110 participants (42%) with normal sleep. Both samples completed the following measures: GSES, Pittsburg Sleep Quality Index, Insomnia Severity Index, Dysfunctional Beliefs and Attitudes about Sleep Scale-10, Pre Sleep Arousal Scale-cognitive subscale, Depression-Anxiety-Stress Scale-21 and sleep diary.

RESULTS

Significant correlations were found between GSES and related measures in both groups. Principal component analysis indicated a single component accounted for 64.77% of total variance in the clinical group. Results of the fit estimates for the one-factor model were consistent with the previously specified fit criteria and adequately fitted the data in the non-clinical group. Statistical analyses showed that the GSES has acceptable internal consistency in terms of Cronbach's Alpha in the clinical (0.75) and non-clinical (0.77) samples. Test-retest reliability for a 4-week interval was significant (r = 0.70). The cut-off point, sensitivity, and specificity of the scale were 6, 85% and 94.5%, respectively.

CONCLUSION

The Persian translated and validated version of the GSES obtained adequate values in psychometric properties in both clinical and non-clinical samples and it can be used for research and clinical purposes in Iran.

A phenomenological inquiry into the experience of sleep: Perspectives of US military veterans with insomnia and serious mental illness

The majority of people with serious mental illness experience insomnia, and insomnia is one of the most frequent reasons for mental health referrals in the Veterans Health Administration. Insomnia also represents a critical obstacle to mental health recovery. Little is known about how military veterans with mental health problems conceptualize their sleep and sleep problems; such information may uncover new avenues for research and treatment. Therefore, the purpose of this study was to explore how veterans with serious mental illness and insomnia experience and understand their sleep, towards the aim of identifying these new avenues. Participants included 20 veterans with insomnia and serious mental illness (i.e. schizophrenia spectrum, bipolar or major depressive disorders, with serious functional impairments). Data were collected via an inductive phenomenological approach using semi-structured interviews. We identified five themes: Sleep to Recharge; Sleep as a Fight; Sleep as Safety or Escape; Sleep as Dangerous; and Military Influence. Participants' relationship with sleep was complex; many associated it with intrusive and troubling hallucinations, paranoia and military experiences, yet at the same time desired sleep for its potential to liberate them from distress. Military mindsets both helped and hindered sleep. These results extend existing models of insomnia development and maintenance, and illuminate phenomena previously unidentified in this underserved veteran population. Clinical and theoretical implications are discussed, as well as new research directions for enhancing therapeutic efficacy.

Comparing the Experience of and Factors Perpetuating Chronic Insomnia Severity Among Young, Middle-Aged, and Older Adults

The prevalence of chronic insomnia is on the rise among young, middle-aged, and older adults. This secondary data analysis examined age-group differences in the experience of and factors perpetuating insomnia severity. Pretest data, obtained from a trial of behavioral interventions, were collected from 742 participants, using psychometrically sound measures of perpetuating factors (sleep habits, unhelpful beliefs, presleep arousal), insomnia experience (symptoms, perceived severity), and consequences or impact on daytime functioning. The age groups reported different insomnia symptoms (difficulty maintaining sleep in older adults) and impact on daytime functioning (poorer in older adults), but the same level of perceived insomnia severity. Unhelpful beliefs about sleep predicted insomnia severity in all age groups, and presleep arousal contributed to insomnia in young adults. The results highlight the importance of adequately managing chronic insomnia to minimize its impact on daytime functioning in all age groups, and of tailoring therapy to their experiences.

Predictors of Nightly Subjective-Objective Sleep Discrepancy in Poor Sleepers over a Seven-Day Period

This study sought to examine predictors of subjective/objective sleep discrepancy in poor sleepers. Forty-two individuals with insomnia symptoms (mean age = 36.2 years, 81% female) were recruited to take part in a prospective study which combined seven days of actigraphy with daily assessment of sleep perceptions, self-reported arousal, sleep effort, and mood upon awakening. A high level of intra-individual variability in measures of sleep discrepancy was observed. Multilevel modelling revealed that higher levels of pre-sleep cognitive activity and lower mood upon awakening were significantly and independently predictive of the underestimation of total sleep time. Greater levels of sleep effort predicted overestimation of sleep onset latency. These results indicate that psychophysiological variables are related to subjective/objective sleep discrepancy and may be important therapeutic targets in the management of insomnia.

Does Consciousness Disappear in Dreamless Sleep?

Consciousness is often said to disappear in deep, dreamless sleep. We argue that this assumption is oversimplified. Unless dreamless sleep is defined as unconscious from the outset there are good empirical and theoretical reasons for saying that a range of different types of sleep experience, some of which are distinct from dreaming, can occur in all stages of sleep. We introduce a novel taxonomy for describing different kinds of dreamless sleep experiences and suggest research methods for their investigation. Future studies should focus on three areas: memory consolidation, sleep disorders, and sleep state (mis)perception. Our proposal suggests new directions for sleep and dream science, as well as for the neuroscience of consciousness, and can also inform the diagnosis and treatment of sleep disorders.