Association of COVID-19 preventive behavior and job-related stress with the sleep quality of healthcare workers one year into the COVID-19 outbreak: a Japanese cross-sectional survey

BACKGROUND

This study aimed to evaluate the association of COVID-19 preventive behavior and job-related stress with sleep quality among healthcare workers (HCWs). We conducted a cross-sectional survey using a questionnaire at the National Center of Neurology and Psychiatry, Tokyo, Japan.

METHODS

A total of 586 participants who completed the questionnaire were eligible for the study. The Pittsburgh Sleep Quality Index was used to evaluate sleep quality. We examined the level of engagement between poor sleep and COVID-19-related infection preventive behaviors, such as avoiding closed spaces, crowded places, and close contact (three Cs), a distance of at least one meter from others, wearing a face mask regularly, washing hands regularly, and working remotely, as well as job-related stress in the work environment, exposure to patients, potential risk of infection, fear of infecting others, need for social confinement, and financial instability. We conducted a hierarchical logistic regression analysis to examine the relationship between poor sleep and COVID-19 preventive behavior, job-related stress, and other covariates, including age, sex, and the Kessler Psychological Distress Scale (K6), which was used to measure non-specific psychological distress.

RESULTS

Poor sleep was observed in 223 (38.1%) participants. Adherence to COVID-19 preventive measures was relatively high: 84.1% of participants answered "always" for wearing a face mask regularly and 83.4% for washing hands regularly. In the multivariate logistic regression analysis, stress in the work environment (odds ratio [OR] = 2.09, 95% confidence interval [CI], 1.37-3.20; p < 0.001), financial instability (OR = 1.73, 95% CI, 1.12-2.67; p < 0.05), and low adherence to working remotely (OR = 1.65, 95% CI, 1.06-2.57; p < 0.05) were independently and significantly associated with poor sleep after controlling for the covariates.

CONCLUSIONS

One year into the COVID-19 pandemic, the poor sleep rates of HCWs remained high. These results emphasize the need to protect HCWs from work environment stress and financial concerns.

Development and validation of the Japanese version of the Bedtime Procrastination Scale (BPS-J)

BACKGROUND

The average sleep duration of Japanese people is shorter than that of people from other countries, and bedtime procrastination is suspected to be one of the factors contributing to this issue. This study aimed to develop and validate the Japanese version of the Bedtime Procrastination Scale (BPS-J).

METHODS

The BPS-J was developed through procedures including the translation and back-translation of the scale, cognitive interviews with 100 participants who reported having experiences of being diagnosed with insufficient sleep syndrome (ISS) or receiving treatment for ISS using open-ended online questionnaires, and expert checking. To investigate the scale's validity and reliability, an online survey was conducted with daytime workers aged 20 - 65 years without a history of sleep disorders other than ISS. Half the participants were retested using the same survey after 14 days. Participants' responses to the Brief Self-Control Scale (BSCS), General Procrastination Scale (GPS), and Munich ChronoType Questionnaire (MCTQ), and data on sleep-related variables such as sleep duration on workdays and the days per week of fatigue or sleep loss, sex, and age, were collected.

RESULTS

We analyzed data from 574 participants to assess scale validity. We then analyzed data from 280 participants to determine test-retest reliability. Confirmatory factor analyses revealed that the two-factor model without Item 2 was most suitable for the BPS-J, unlike other language versions. Regardless of the full-item model or the model with Item 2 eliminated, sufficient reliability and significant correlations with the BSCS, GPS, MCTQ, and sleep-related variables such as sleep duration per night on work days, days per week of feeling fatigued, and days per week of sleep loss were observed. Logistic and linear regressions showed that the relationships between the BPS-J, sleep-related variables, and MCTQ were maintained after adjusting for sex and age.

CONCLUSION

The BPS-J had sufficient validity and reliability. Further, eliminating Item 2 from the original version of the BPS strengthened the ability to survey Japanese daytime workers.

Association between sleep duration and antibody acquisition after mRNA vaccination against SARS-CoV-2

Introduction

Sleep enhances the antibody response to vaccination, but the relationship between sleep and mRNA vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is not fully understood.

Methods

In this prospective observational study, we investigated the influence of sleep habits on immune acquisition induced by mRNA vaccines against SARS-CoV-2 in 48 healthy adults (BNT-162b2, n=34; mRNA-1273, n=14; female, n=30, 62.5%; male, n=18, 37.5%; median age, 39.5 years; interquartile range, 33.0-44.0 years) from June 2021 to January 2022. The study measured sleep duration using actigraphy and sleep diaries, which covered the periods of the initial and booster vaccinations.

Results

Multivariable linear regression analysis showed that actigraphy-measured objective sleep duration 3 and 7 days after the booster vaccination was independently and significantly correlated with higher antibody titers (B=0.003; 95% confidence interval, 0.000-0.005; Beta=0.337; p=0.02), even after controlling for covariates, including age, sex, the type of vaccine, and reactogenicity to the vaccination. Associations between acquired antibody titer and average objective sleep duration before vaccination, and any period of subjective sleep duration measured by sleep diary were negligible.

Discussion

Longer objective, but not subjective, sleep duration after booster vaccination enhances antibody response. Hence, encouraging citizens to sleep longer after mRNA vaccination, especially after a booster dose, may increase protection against SARS-CoV-2.

Study registration

This study is registered at the University Hospital Medical Information Network Center (UMIN: https://www.umin.ac.jp) on July 30, 2021, #UMIN000045009.

Association between health anxiety dimensions and preventive behaviors during the COVID-19 pandemic among Japanese healthcare workers

Objective

Health anxiety (HA), defined as excessive worry about having a serious medical condition, may affect preventive behaviors during the coronavirus disease 2019 (COVID-19) pandemic. We examined the distinct role of two dimensions of HA-perceived likelihood (probability dimension) and awfulness of illness (awfulness dimension)-in self-protection, as reflected in preventive behaviors during the pandemic.

Methods

Participants comprised 657 healthcare workers. Data were collected between February 24 and 26, 2021. The Short Health Anxiety Inventory determined the HA dimensions. Adherence to the government's recommendations for COVID-19 preventive behaviors was self-rated. An independent association between each HA dimension and participants' adherence to the recommendations was examined using multivariable regression.

Results

Within the analyzed sample of 560 subjects, severe HA was observed in 9.1 %. The more the participants felt awful, the less frequently they engaged in the recommended preventive behaviors (adjusted odds ratio = 0.993, 95 % confidence interval: 0.989, 0.998, p = 0.003) regardless of their profession, working position, psychological distress, sleep disturbance, and current physical diseases. However, the probability dimension was not associated with their preventive behaviors.

Conclusion

The awfulness dimension of HA could be a more sensitive marker of preventive behaviors than the probability dimension. Paying particular attention to the awfulness dimension may help optimize self-protection strategies during the COVID-19 pandemic. A two-dimensional understanding of HA may be useful for the maintenance of the healthcare system and public health as well as healthcare workers' own health.

A prospective study of the association of weekend catch-up sleep and sleep duration with mortality in middle-aged adults

Health effects of weekend catch-up sleep (CUS) could differ depending on both the ability to obtain sufficient sleep during weekdays and amount of weekend CUS required to compensate for sleep lost during the week. Using data from 3128 middle-aged (40-64 years) participants of the Sleep Heart Health Study, we examined the longitudinal association of these two aspects of sleep with all-cause mortality. CUS was calculated as the difference in self-reported habitual sleep duration between weekends and weekdays, and classified into no, short (1 h), and long (2 h or more) CUS. Polysomnography-measured total sleep time, representing the ability to obtain sufficient sleep, was classified into short (< 360 min) or normal (≥ 360 min) sleep durations. We estimated multivariable-adjusted mortality hazard ratios (HRs) and 95% confidence intervals (CIs) for six groups divided by the extent of CUS and sleep duration. Participants were followed up for a median (interquartile range) of 12.3 (11.3-13.5) years. Short weekend CUS with normal sleep duration was associated with lower mortality compared to no CUS with normal sleep duration (HR, 0.48; 95% CI 0.27-0.83). When stricter cutoffs were applied for sleep durations, while the protective effect of short CUS with normal sleep duration (≥ 390 min) was strengthened (HR, 0.36; 95% CI 0.17-0.78), the harmful effect of short CUS with short sleep duration (< 330 min) emerged (HR, 1.84; 95% CI 1.08-3.14). Results highlight the importance of balancing sleep ability and CUS. Sufficient sleep may reduce weekday sleep debt and only a short CUS would be required on weekends, improving mortality in middle-aged adults.

Supplementary Information

The online version contains supplementary material available at 10.1007/s41105-023-00460-6.

The effect of nonrestorative sleep on incident hypertension 1-2 years later among middle-aged Hispanics/Latinos

BACKGROUND

Insomnia is known to be a major risk factor for incident hypertension. Nonrestorative sleep (NRS), which refers to insufficiently rested sleep, has reported to associate with various diseases. This study aimed to investigate the longitudinal association between insomnia-related symptoms including NRS and incident hypertension 1-2 years later by age group (young, 18-39 years and middle-age, 40-64 years) using existing cohort data involving Hispanics/Latinos.

METHODS

This study included 1100 subjects who had participated in both the Hispanic Community Health Study/Study of Latinos and its follow-up study, the Sueño Ancillary Study, and met additional eligibility criteria. Incident hypertension was assessed by self-reported history and/or the use of antihypertensives. The Women's Health Initiative Insomnia Rating Scale (WHIIRS) was used to evaluate insomnia-related symptoms (difficulty initiating sleep, difficulty maintaining sleep, early morning awakening, difficulty returning to sleep, and NRS). Logistic regression analyses were conducted to assess the degree to which insomnia-related symptoms at baseline predicted incident hypertension.

RESULTS

Among the participants (64% middle-aged, 36% young adults), 140 (12.7%) developed hypertension during the follow-up period. Among the sleep-related symptoms, only NRS predicted incident hypertension after adjusting for sociodemographic factors and physical condition (odds ratio: 1.88, 95% confidence interval: 1.10-3.21, p = 0.022) in middle-aged adults. None of the insomnia-related symptoms were associated with incident hypertension in the young adults. No association was found between WHIIRS-defined insomnia (total score ≥ 9) and incident hypertension in middle-aged adults or young adults.

CONCLUSION

The present findings suggest the importance of focusing on NRS to help prevent the development of hypertension in middle-aged adults.

Corrigendum: Decrease in social zeitgebers is associated with worsened delayed sleep-wake phase disorder: findings during the pandemic in Japan

[This corrects the article DOI: 10.3389/fpsyt.2022.898600.].

Exploring the role of empathy in prolonged grief reactions to bereavement

Grief reactions to the bereavement of a close individual could involve empathy for pain, which is fundamental to social interaction. To explore whether grief symptoms interact with social relatedness to a person to whom one directs empathy to modulate the expression of empathy, we administered an empathy task to 28 bereaved adults during functional magnetic resonance imaging, in which participants were subliminally primed with facial stimuli (e.g., faces of their deceased or living relative, or a stranger), each immediately followed by a visual pain stimulus. Individuals' grief severity promoted empathy for the pain stimulus primed with the deceased's face, while it diminished the neural response to the pain stimulus primed with the face of either their living relative or a stranger in the medial frontal cortex (e.g., the right dorsal anterior cingulate cortex). Moreover, preliminary analyses showed that while the behavioral empathic response was promoted by the component of "longing" in the deceased priming condition, the neural empathic response was diminished by the component of "avoidance" in the stranger priming condition. Our results suggest an association between grief reactions to bereavement and empathy, in which grief symptoms interact with interpersonal factors to promote or diminish empathic responses to others' pain.

Treatment strategy for insomnia disorder: Japanese expert consensus

Purpose

There is a lack of evidence regarding answers for clinical questions about treating insomnia disorder. This study aimed to answer the following clinical questions: (1) how to use each hypnotic and non-pharmacological treatment differently depending on clinical situations and (2) how to reduce or stop benzodiazepine hypnotics using alternative pharmacological and non-pharmacological treatments.

Methods

Experts were asked to evaluate treatment choices based on 10 clinical questions about insomnia disorder using a nine-point Likert scale (1 = "disagree" to 9 = "agree"). The responses of 196 experts were collected, and the answers were categorized into first-, second-, and third-line recommendations.

Results

The primary pharmacological treatment, lemborexant (7.3 ± 2.0), was categorized as a first-line recommendation for sleep initiation insomnia, and lemborexant (7.3 ± 1.8) and suvorexant (6.8 ± 1.8) were categorized as the first-line recommendations for sleep maintenance insomnia. Regarding non-pharmacological treatments for primary treatment, sleep hygiene education was categorized as the first-line recommendation for both sleep initiation (8.4 ± 1.1) and maintenance insomnia (8.1 ± 1.5), while multicomponent cognitive behavioral therapy for insomnia was categorized as the second-line treatment for both sleep initiation (5.6 ± 2.3) and maintenance insomnia (5.7 ± 2.4). When reducing or discontinuing benzodiazepine hypnotics by switching to other medications, lemborexant (7.5 ± 1.8) and suvorexant (6.9 ± 1.9) were categorized as first-line recommendations.

Conclusion

Expert consensus indicates that orexin receptor antagonists and sleep hygiene education are recommended as first-line treatments in most clinical situations to treat insomnia disorder.

Transdiagnostic association between subjective insomnia and depressive symptoms in major psychiatric disorders

In psychiatric disorders, comorbid depressive symptoms are associated with clinically important issues such as reduced quality of life, a poor prognosis, and increased suicide risk. Previous studies have found a close relationship between insomnia and depressive symptoms in major depressive disorder (MDD), and that actively improving insomnia heightens the improvement of depressive symptoms. This study aimed to investigate whether the association between insomnia and depressive symptoms is also found in other psychiatric disorders besides MDD. The subjects were 144 patients with MDD (n = 71), schizophrenia (n = 25), bipolar disorder (n = 22), or anxiety disorders (n = 26). Sleep status was assessed subjectively and objectively using the Athens Insomnia Scale (AIS) and sleep electroencephalography (EEG), respectively. Sleep EEG was performed using a portable EEG device. Depressive symptoms were assessed using the Beck Depression Inventory. Subjective insomnia, as defined by the AIS, was associated with depressive symptoms in all disorders. Moreover, in schizophrenia, a relation between depressive symptoms and insomnia was also found by objective sleep assessment methods using sleep EEG. Our findings suggest that the association between subjective insomnia and depressive symptoms is a transdiagnostic feature in major psychiatric disorders. Further studies are needed to clarify whether therapeutic interventions for comorbid insomnia can improve depressive symptoms in major psychiatric disorders, similar to MDD.

Nonrestorative sleep is a risk factor for metabolic syndrome in the general Japanese population

BACKGROUND

This longitudinal study aimed to investigate the effects of nonrestorative sleep on developing metabolic syndrome (MetS) and related diseases in a general Japanese middle-aged population.

METHODS

Overall, 83,224 adults without MetS (mean age: 51.5 ± 3.5 years) from the Health Insurance Association in Japan were followed up for a maximum of 8 years between 2011 and 2019. The Cox proportional hazard method was used to determine whether nonrestorative sleep, assessed using a single-item question, was significantly associated with the respective development of MetS, obesity, hypertension, diabetes, and dyslipidemia. The MetS criteria were adopted by the Examination Committee for Criteria of Metabolic Syndrome in Japan.

RESULTS

The mean follow-up duration was 6.0 years. The incidence rate of MetS was 50.1 person-years/1,000 during the study period. Data suggested that nonrestorative sleep was associated with MetS (hazard ratio [HR]: 1.12, 95% confidence interval [CI]: 1.08-1.16) and other disorders, such as obesity (HR: 1.07, 95% CI: 1.02-1.12), hypertension (HR: 1.07, 95% CI: 1.04-1.11), and diabetes (HR: 1.07, 95% CI: 1.01-1.12) but not with dyslipidemia (HR: 1.00, 95% CI: 0.97-1.03).

CONCLUSIONS

Nonrestorative sleep is associated with the development of MetS and many of its core components in the middle-aged Japanese population. Therefore, assessing nonrestorative sleep may help identify individuals at a risk of MetS development.

Longitudinal assessment of lifestyle factors associated with nonrestorative sleep in Japan

OBJECTIVE

Nonrestorative sleep (NRS) is common in the general global population. This study surveyed the incident/remission rate of NRS and identified related lifestyle factors in a general Japanese adult cohort.

METHODS

Data from a Japanese health check-based cohort between the fiscal years 2011 and 2018 were obtained. NRS was assessed through a single item question, and socio-demographic and clinical data were assessed through self-reports. To identify potential correlates of NRS incidence/remission, Cox regression analysis (or survival analysis) was performed.

RESULTS

Among the 135 609 individuals surveyed at baseline, data from 93 548 were considered for analysis. NRS exhibited incidence and remission rates of 11.3% and 15.4%, respectively. New NRS incidence was predicted by eating fast (hazard ratio [HR]: 1.07, 95% confidence interval [CI]: 1.04-1.10), dining close to bedtime (HR: 1.33, 95% CI: 1.27-1.38), midnight snacking (HR: 1.09, 95% CI: 1.04-1.13), skipping breakfast (HR: 1.16, 95% CI: 1.10-1.22), non-regular exercise (HR: 1.12, 95% CI: 1.07-1.17), lower levels of physical activity (HR: 1.19, 95% CI: 1.14-1.24), and slow walking speed (HR: 1.34, 95% CI: 1.29-1.39), while heavy drinking was less predictive of NRS. However, the same factors (except for heavy drinking) were found to predict NRS remission.

CONCLUSIONS

We found that unhealthy lifestyle behaviors, particularly dining close to bedtime and slow walking speed, were positively associated with NRS incidence, while they were negatively associated with NRS remission. These results can be useful in developing more effective health promotion policies to achieve good sleep.

Correction to: Comparison of the usability of an automatic sleep staging program via portable 1-channel electroencephalograph and manual sleep staging with traditional polysomnography

[This corrects the article DOI: 10.1007/s41105-022-00421-5.].

Comparison of the usability of an automatic sleep staging program via portable 1-channel electroencephalograph and manual sleep staging with traditional polysomnography

Automatic algorithms are a proposed alternative to manual assessment of polysomnography data for analyzing sleep structure; however, none are acceptably accurate for clinical use. We investigated the feasibility of an automated sleep stage scoring system called Sleep Scope, which is intended for use with portable 1-channel electroencephalograph, and compared it with the traditional polysomnography scoring method. Twenty-six outpatients and fourteen healthy volunteers underwent Sleep Scope and polysomnography assessments simultaneously. Polysomnography records were manually scored by three sleep experts. Sleep Scope records were scored using a dedicated auto-staging algorithm. Sleep parameters, including total sleep time, sleep latency, wake after sleep onset, and sleep efficiency, were calculated. The epoch-by-epoch pairwise concordance based on the classification of sleep into five stages (i.e., wake, rapid eye movement, N1, N2, and N3) was also evaluated after validating homogeneity and bias between Sleep Scope and polysomnography. Compared with polysomnography, Sleep Scope seemed to overestimate sleep latency by approximately 3 min, but there was no consistent tendency in bias in other sleep parameters. The Κ values ranged from 0.66 to 0.75 for experts' inter-rater polysomnography scores and from 0.62 to 0.67 for Sleep Scope versus polysomnography scores, which indicated sufficient agreement in the determination of sleep stages based on the Landis and Koch criteria. We observed sufficient concordance between Sleep Scope and polysomnography despite lower concordance in sleep disorder patients. Thus, this auto-staging system might serve as a novel clinical tool for reducing the time and expenses required of medical staff and patients.

Supplementary Information

The online version contains supplementary material available at 10.1007/s41105-022-00421-5.

Effect of discontinuation of lemborexant following long-term treatment of insomnia disorder: Secondary analysis of a randomized clinical trial

Discontinuing long-term pharmacotherapy for insomnia can result in rebound insomnia or withdrawal symptoms and suboptimal treatment. Post hoc analyses evaluated rebound insomnia and withdrawal symptoms among the subset of subjects from a phase III, 12-month, global, multicenter, randomized, double-blind, parallel-group study who completed 12 or 6 months of active treatment and follow-up period. Study E2006-G000-303 (Study 303) included adults (N = 655) with subjective sleep-onset latency ≥30 min and/or subjective wake-after-sleep onset ≥60 min at least three times weekly during the 4 weeks before enrollment. Subjects were randomized 1:1:1 to lemborexant 5 mg (LEM5) or 10 mg (LEM10) or placebo for 6 months. Thereafter, for an additional 6 months, LEM5- and LEM10-treated subjects continued lemborexant and the placebo group was rerandomized 1:1 to LEM5 or LEM10. Month 12 was followed by abrupt discontinuation and a 2-week end-of-study follow-up. Using daily electronic sleep diaries, patients reported (subjective) sleep end points (sleep-onset latency, wake-after-sleep onset, sleep efficiency, and total sleep time). Withdrawal symptoms were assessed using the Tyrer Benzodiazepine Withdrawal Symptoms Questionnaire (T-BWSQ). Sleep outcome improvements with lemborexant at month 12 were generally maintained throughout the 2-week off-treatment period wherein <20% of subjects experienced significant worsening of insomnia symptoms versus screening. There was no evidence of withdrawal symptoms by T-BWSQ following lemborexant discontinuation. This analysis demonstrates rebound insomnia is unlikely to occur with lemborexant, and its effectiveness is maintained after abrupt discontinuation without placebo replacement following 6-12 months of treatment.

Toe grip force of the dominant foot is associated with fall risk in community-dwelling older adults: a cross-sectional study

Background

It is unclear whether the toe grip force (TGF) of the dominant foot (DF) and the lower limb function asymmetry (LLFA) in older adults are associated with fall risk. Therefore, this study aimed to investigate the effect of lower limb properties (such as TGF, muscle strength, and plantar sensation) on the risk of falls in older adults, while considering the foot dominance and asymmetry of lower limb function.

Methods

This study was a cross-sectional study. We determined whether the lower limb function of the DF and non-dominant foot (non-DF) and LLFA had any effect on the fall risk in 54 older adults (mean ± standard deviation: 72.2 ± 6.0, range: 60–87 years). We examined the participants’ fall history, Mini-Mental State Examination (MMSE) score, lower limb function, and LLFA. To determine fall risk factors, we performed logistic regression analysis, with presence or absence of falls as the dependent variable.

Results

The independent variables were age, sex, MMSE score, two-point discrimination of the heel (non-DF) as plantar sensation index, and the TGF of both feet. Only the TGF of the DF was identified as a risk factor for falls (p < 0.05).

Conclusions

In older adults, clinicians should focus on the TGF of the DF as a risk factor for falls.

Trial registration

This study was retrospectively registered. https://center6.umin.ac.jp/cgi-bin/ctr/ctr_up_rec_f1.cgi.

Associations of nonrestorative sleep and insomnia symptoms with incident depressive symptoms over 1-2 years: Longitudinal results from the Hispanic Community Health Study/Study of Latinos and Sueño Ancillary Study

BACKGROUND

Nonrestorative sleep (NRS), defined as insufficiently rested or refreshed sleep, is considered to play an important role in the development of depression. The aim of this study is to investigate the predictive ability of insomnia-related symptoms, including NRS, for incident depressive symptoms (DEPs) in a longitudinal manner.

METHODS

We used data of 1196 samples aged 18-64 years who participated in both the Hispanic Community Health Study/Study of Latinos conducted in 2008-2010 and the follow-up study (Sueño Ancillary Study) conducted in 2010-2013. DEPs and insomnia-related symptoms (difficulty initiating sleep [DIS], difficulty maintaining sleep [DMS], early morning awakening [EMA], difficulty returning to sleep [DRS], and NRS) were evaluated by the 10-item Center for Epidemiologic Studies Depression Scale and the Women's Health Initiative Insomnia Rating Scale, respectively. A logistic regression analysis was used to evaluate the predictive ability of each insomnia-related symptom at baseline for incident DEPs in couple-years.

RESULTS

In the univariate logistic regression analysis, all insomnia-related symptoms had significant associations with incident DEPs (DIS, odds ratio [OR] = 1.6; DMS, OR = 1.6; EMA, OR = 1.5; DRS, OR = 1.9; NRS, OR = 2.5). After adjusting for sociodemographic factors and the confounding effects of other insomnia-related symptoms, only NRS (OR = 2.2, 95% confidence interval = 1.4-3.5, p = .001) was significantly associated with incident DEPs.

CONCLUSIONS

NRS was a risk factor for incident DEPs, which includes a predictive ability for other insomnia-related symptoms. Our results suggest that focusing on NRS is an effective strategy for preventing depression in public health promotions.

Sleep disturbance and health-related quality of life in Parkinson's disease: A clear correlation between health-related quality of life and subjective sleep quality

INTRODUCTION

Comorbid insomnia and poor sleep quality in Parkinson's disease (PD) are associated with a poor health-related quality of life (HRQoL). However, the relationship between HRQoL and sleep measures obtained using polysomnography (PSG) remains unclear. We aimed to examine the association between various sleep measures and HRQoL in PD patients.

METHODS

We retrospectively included patients with PD who underwent PSG and responded to self-administered questionnaires including the Pittsburgh Sleep Quality Index (PSQI) and Medical Outcomes Study 36-Item Short-Form Health Survey.

RESULTS

The patients' (n = 120) mean age was 67.06 (SD = 8.77) years, and their mean Hoehn and Yahr stage was 2.25 (SD = 0.78). A higher PSQI score (worse subjective sleep quality) was correlated in PSG with shorter sleep latency, less N1 sleep, and more N2 sleep. Multiple regression analysis showed that the total PSQI score correlated with both physical and mental HRQoL (p < 0.001 in both cases). However, neither type of HRQoL studied correlated with objective sleep measures, including indicators of sleep architecture, sleep-disordered breathing, and sleep related movement disorders.

CONCLUSION

Despite the association between subjective sleep quality and HRQoL, the associations between objective measures and HRQoL were negligible. Objective sleep fragmentation may not be perceived as a sleep disturbance in patients with PD, and therefore may not adversely affect their subjective health, given the paradoxical correlation between PSQI score and sleep architecture.

Periocular Skin Warming Promotes Sleep Onset Through Heat Dissipation From Distal Skin in Patients With Insomnia Disorder

STUDY OBJECTIVES

Periocular skin warming before bedtime has been demonstrated to improve subjective sleep initiation in healthy adults with sleep difficulties scored six or higher in the Pittsburgh Sleep Questionnaire Index. This study aimed to investigate the effects of periocular skin warming on sleep initiation and thermoregulation processes in patients with insomnia disorder.

METHODS

Participants included those with sleep difficulty (n = 22) and those with insomnia disorder (n = 16). Individuals from both groups were assessed at baseline (habitual sleep-wake schedule) and after two intervention conditions (use of a warming eye mask or a sham eye mask before habitual bedtime). The subjective and electroencephalographic sleep onset latency, along with proximal and distal skin temperature after periocular skin warming, were evaluated.

RESULTS

Periocular skin warming reduced objective sleep onset latency in independently of the group. Foot temperature and foot-proximal temperature gradient after getting into bed increased with periocular skin warming in independently of the group. However, the increase in hand temperature was observed only in the insomnia disorder group. Periocular skin warming also increased the normalized high frequency component of heart rate variability in independently of the group. The reduction of objective sleep onset latency was strongly associated with heat dissipation from the foot skin region.

CONCLUSION

These results suggest that periocular skin warming promotes sleep initiation by enhancing heat dissipation from the distal skin regions in individuals with sleep difficulty and insomnia disorder. Periocular skin warming could thus be a novel non-pharmacological therapy for insomnia disorder.

Decrease in Social Zeitgebers Is Associated With Worsened Delayed Sleep-Wake Phase Disorder: Findings During the Pandemic in Japan

BACKGROUND

Delay in sleep-wake rhythms was observed in the general population during the coronavirus disease 2019 (COVID-19) pandemic. Patients with delayed sleep-wake phase disorder (DSWPD) may have also experienced exacerbation of symptoms, but no studies have investigated this topic. In this study, we aimed to retrospectively examine the changes in symptoms of outpatients with DSWPD both before and during the pandemic and to identify the factors associated with the exacerbation of sleep-wake rhythms.

METHODS

We included outpatients with DSWPD aged 16 years or older who visited the outpatient clinic due to sleep disorders between January and September 2020. Decreased social zeitgebers was defined as a reduction of 50% or more in the frequency of commuting to school or work during the COVID-19 pandemic. The severity of DSWPD was assessed using the clinical global impressions - severity of illness (CGI-S) at two points: before and during the pandemic. We defined the worsened, unchanged, and improved groups as those whose CGI-S scores worsened by at least one point, remained unchanged, and improved by at least one point, respectively. Multivariate logistic regression analysis was performed to determine the factors associated with worsened DSWPD symptoms.

RESULTS

Sixty patients with DSWPD were eligible for this study. Even before the pandemic, patients who were unemployed or did not attend school tended to show more severe DSWPD symptoms. During the pandemic, 27 patients belonged to the worsened group; 28 patients, unchanged group; and 5 patients, improved group. Decreased social zeitgebers (odds ratio [OR] = 6.668, 95% confidence interval [CI]: 1.653-26.891, p < 0.05) and comorbid mood disorders (OR = 8.876, 95% CI: 1.714-45.974, p < 0.05) showed independent significant associations with the worsening of DSWPD symptoms.

CONCLUSIONS

During the pandemic, the symptoms of DSWPD tended to worsen. The obtained findings emphasize the importance of social zeitgebers, suggesting the need for external motivation in DSWPD treatment.

Association of Subjective Quality and Quantity of Sleep with Quality of Life among a General Population

This study aimed to determine whether both subjective sleep quality and sleep duration are directly associated with quality of life (QOL), as well as indirectly associated with QOL through insomnia symptoms. Individuals aged 20–69 years without mental illness (n = 9305) were enrolled in this web-based cross-sectional survey. The Short Form-8 was used to assess physical and mental QOL. We used the Pittsburgh Sleep Quality Index (PSQI) and extracted items related to subjective sleep quality and sleep duration. Insomnia symptoms were also extracted from the PSQI. The hypothesized models were tested using structural equation modeling. Worse sleep quality, but not shorter sleep duration, was related to worse physical QOL. Both worse sleep quality and shorter sleep duration were related to worse mental QOL. Insomnia symptoms mediated these relationships. Subgroup analyses revealed a U-shaped relationship between sleep duration and physical/mental QOL. However, the relationship between sleep quality and physical/mental QOL was consistent regardless of sleep duration. The results suggest that subjective sleep quality has a more coherent association with QOL than subjective sleep duration. Because of its high feasibility, a questionnaire on overall sleep quality could be a useful indicator in future epidemiological studies of strategies for improving QOL.

Development and acceptability of a decision aid for chronic insomnia considering discontinuation of benzodiazepine hypnotics

Aim

To describe the development and acceptability of a decision aid (DA) for chronic insomnia considering discontinuation of benzodiazepine (BZD) and benzodiazepine receptor agonist (BZRA) hypnotics, and if discontinuing, tapering with or without cognitive behavioral therapy for insomnia (CBT‐I).

Methods

We reviewed relevant literature describing chronic insomnia to identify options. We used the results of the systematic review and meta‐analysis conducted previously to determine the related outcomes of two options: discontinuation of BZD/BZRA hypnotics by gradual tapering alone and discontinuation of BZD/BZRA hypnotics by gradual tapering with CBT‐I. We then developed a prototype of DA following the International Patient Decision Aid Standards. A mixed methods survey was conducted to assess the acceptability among patients and healthcare providers.

Results

The prototype consisted of a description of insomnia, options of continuing or discontinuing BZD/BRZA hypnotics (if discontinuing, the options of tapering hypnotics with or without CBT‐I), pros and cons of each option, and a value clarification exercise. Patients (n = 24) reported that the DA had acceptable language (79%), adequate information (71%), and well‐balanced presentation (91%). Healthcare providers (n = 20) also provided favorable feedback.

Conclusion

We developed a DA for chronic insomnia considering discontinuation of BZD/BRZA hypnotics, which was acceptable for stakeholders. The developed DA was designed to support patients and healthcare providers to make a decision about whether to discontinue BZD/BRZA hypnotics.

A Cross-Sectional Study of Evening Hyperphagia and Nocturnal Ingestion: Core Constituents of Night Eating Syndrome with Different Background Factors

This web-based cross-sectional survey aimed to elucidate the differences between the two core symptoms of night eating syndrome (NES): evening hyperphagia and nocturnal ingestion in the general Japanese population aged 16–79 years. Participants who consumed at least 25% of daily calories after dinner were defined as having evening hyperphagia. Those who consumed food after sleep initiation at least twice a week were determined to have nocturnal ingestion. Of the 8348 participants, 119 (1.5%) were categorized in the evening hyperphagia group, 208 (2.6%) in the nocturnal ingestion group, and 8024 in the non-NES group. Participants with evening hyperphagia and nocturnal ingestion had significantly higher anxiety scores (p < 0.05 and p < 0.001, respectively) and depression (p < 0.001 for both) than those without NES. Multiple logistic regression analysis revealed that evening hyperphagia was significantly and independently associated with higher body mass index, shorter sleep duration, later sleep-wake schedule, and higher insomnia score, while nocturnal ingestion was significantly and independently associated with younger age, smoking habit, living alone, earlier sleep-wake schedule, and higher insomnia score. Sleep duration and sleep-wake schedule characteristics in the two groups were opposite, suggesting differences in the sleep pathophysiology mechanisms.

Psychological burden of attention-deficit/hyperactivity disorder traits on medical workers under the COVID-19 outbreak: a cross-sectional web-based questionnaire survey

OBJECTIVES

There are numerous reports on the psychological burden of medical workers after the COVID-19 outbreak; however, no study has examined the influence of developmental characteristics on the mental health of medical workers. The objective of this study was to examine whether the developmental characteristics of medical workers are associated with anxiety and depression after the COVID-19 outbreak.

DESIGN

We conducted an online cross-sectional questionnaire survey in October 2020.

PARTICIPANTS AND SETTING

The data of 640 medical workers were analysed. The questionnaire included items on sociodemographic data, changes in their life after the COVID-19 outbreak and symptoms of depression, anxiety, attention-deficit/hyperactivity disorder (ADHD) traits and autism spectrum disorder traits.

MAIN OUTCOMES

Depression symptoms were assessed by the Patient Health Questionnaire-9 and anxiety symptoms were assessed by the Generalised Anxiety Disorder-7. A series of hierarchical multiple regression analyses were performed to test the effects of developmental characteristics on depression and anxiety symptoms after controlling for sociodemographic factors and changes in participants' lives after the COVID-19 outbreak.

RESULTS

Increases in physical and psychological burden were observed in 49.1% and 78.3% of the subjects, respectively. The results of a multiple regression analysis showed that ADHD traits were significantly associated with both depression (β=0.390, p<0.001) and anxiety (β=0.426, p<0.001). Autistic traits were significantly associated with depression (β=0.069, p<0.05) but not anxiety. Increased physical and psychological burden, being female, medical workers other than physicians and nurses, fear of COVID-19 and experience of discrimination were also significantly associated with both depression and anxiety.

CONCLUSION

Globally, the burden on medical workers increased. This study suggested that medical workers with higher ADHD traits may need special attention during the COVID-19 pandemic.

Factors causing a relapse of major depressive disorders following successful electroconvulsive therapy: A retrospective cohort study

BACKGROUND

Electroconvulsive therapy (ECT) is used to treat major depressive disorder (MDD). Relapse is often observed even after successful ECT, followed by adequate pharmaceutical treatment for MDD.

AIM

To investigate the diagnostic factors and treatment strategies associated with depression relapse.

METHODS

We analyzed the relationships between relapse, the diagnostic change from MDD to bipolar disorder (BP), and treatment after the initial ECT. We performed a 3-year retrospective study of the prognoses of 85 patients of the Shiga University of Medical Science Hospital. The relative risk of relapse of depressive symptoms was calculated based on the diagnostic change from MDD to BP. A receiver operating characteristic (ROC) curve was generated to evaluate the predictive accuracy of diagnostic changes from MDD to BP based on the duration between the first course of ECT and the relapse of depressive symptoms.

RESULTS

Eighty-five patients initially diagnosed with MDD and successfully treated with ECT were enrolled in the study. Compared with the MDD participants, more BP patients experienced relapses and required continuation and/or maintenance ECT to maintain remission (65.6% vs 15.1%, P < 0.001; relative risk = 4.35, 95%CI: 2.19-8.63, P < 0.001). Twenty-nine patients experienced relapses during the three-year follow-up. In 21 (72.4%, 21/29) patients with relapse, the diagnosis was changed from MDD to BP. The duration from the first course of ECT to relapse was shorter for the BP patients than for the MDD patients (9.63 ± 10.4 mo vs 3.38 ± 3.77 mo, P = 0.022); for most patients, the interval was less than one month. The relative risk of depressive symptoms based on diagnostic changes was 4.35 (95% confidence interval: 2.19–8.63, P < 0.001), and the area under the ROC curve for detecting diagnostic changes based on relapse duration was 0.756 (95%CI: 0.562-0.895, P = 0.007).

CONCLUSION

It may be beneficial to suspect BP and change the treatment strategy from MDD to BP for patients experiencing an early relapse.

The efficacy of add-on ramelteon and subsequent dose reduction in benzodiazepine derivatives/Z-drugs for the treatment of sleep-related eating disorder and night eating syndrome: a retrospective analysis of consecutive patients

STUDY OBJECTIVES

The objective of this study was to determine the efficacy of ramelteon in treating abnormal eating behavior in patients with sleep-related eating disorder and/or night eating syndrome.

METHODS

We retrospectively reviewed the medical records of patients with sleep-related eating disorder/night eating syndrome at the Yoyogi Sleep Disorder Center from November 2013 to November 2018. We categorized patients as ramelteon treatment responders when the frequency of nighttime eating per week decreased to less than half of that before treatment.

RESULTS

Forty-nine patients were included in the analysis. The mean frequency of eating behavior (per week) (standard deviation) at baseline and post-ramelteon treatment was significantly different, at 5.3 (2.2) and 3.2 (3.0), respectively (P < .001). Twenty-one patients (42.9%) were classified as responders. Adverse events, all of which were mild daytime somnolence, were observed in 5 patients. There were significantly more individuals using benzodiazepine derivatives and Z-drugs before treatment and those with coexisting delayed sleep-wake phase disorder in the responder group than in the nonresponder group (P < .001 and P < .05, respectively). The mean benzodiazepine derivatives and Z-drugs dose significantly decreased from baseline to post-ramelteon treatment within the responder group (P < .05). This trend was not observed in the nonresponder group. Meanwhile, the sleep midpoint of patients with sleep-related eating disorder/night eating syndrome and delayed sleep-wake phase disorder did not significantly change after treatment.

CONCLUSIONS

Our results indicate that ramelteon is a candidate treatment for sleep-related eating disorder/night eating syndrome. The effects of ramelteon might have occurred primarily through the reduction in benzodiazepine derivatives and Z-drugs rather than through the improvement in sleep-wake rhythm dysregulation.

Prevalence of Circadian Rhythm Sleep-Wake Disorder in Outpatients with Schizophrenia and Its Association with Psychopathological Characteristics and Psychosocial Functioning

The prevalence of circadian rhythm sleep-wake disorder (CRSWD) among patients with schizophrenia is not clear. The effect of comorbid CRSWD on such patients has also not been fully evaluated yet. Outpatients with schizophrenia in the maintenance phase who visited Tokyo Women’s Medical University Hospital between April 2018 and March 2019 participated in this study. The Brief Psychiatric Rating Scale (BPRS), the Clinical Global Impressions–Severity Illness Scale (CGI-S), Global Assessment of Functioning (GAF), World Health Organization Disability Assessment Schedule II, Insomnia Severity Index (ISI), and Morningness–Eveningness Questionnaire (MEQ) were administered, and the patient responses with and without CRSWD were compared. Of the 105 patients with schizophrenia, 19 (18.1%) had CRSWD. There were trends toward higher BPRS and lower GAF scores in the CRSWD group than in the non-CRSWD group, although these did not reach statistical significance following a false discovery rate correction. Among the BPRS subitems, the anxiety scores were significantly higher in the CRSWD group than in the non-CRSWD group (p < 0.01). CRSWD was highly prevalent among patients with schizophrenia in the maintenance phase. Comorbidities of CRSWD may affect psychopathological characteristics and psychosocial functioning.

The effect of short or long sleep duration on quality of life and depression: an internet-based survey in Japan

BACKGROUND

To date, no previous studies have evaluated the relationship between sleep duration and quality of life (QOL) or depression in the general population after controlling for daytime sleepiness and sleep disturbances.

METHODS

A web-based cross-sectional survey was conducted with 8698 subjects aged 20-69 years. We examined the relationships between weekday sleep duration and daytime sleepiness, sleep disturbance, QOL and depression, using the Epworth Sleepiness Scale, Pittsburgh Sleep Quality Index (without the item for sleep duration), 8-item Short Form and Center for Epidemiological Studies Depression Scale (CES-D).

RESULTS

Daytime sleepiness tended to increase in proportion to shorter weekday sleep durations. Sleep disturbances, physical and mental QOL, and CES-D scores were worse in both the shorter and longer sleep groups compared with the group with 7-8 h of sleep. Hierarchical logistic regression analyses revealed that short sleep duration but not long sleep duration was significantly associated with reduction of both physical and mental QOL, even after controlling for the presence of daytime sleepiness and sleep disturbance. Both short and long sleep duration were independently and significantly correlated with depression after controlling for daytime sleepiness; however, there was no statistically significant association after adjusting for the effects of sleep disturbance.

CONCLUSIONS

The results suggested adverse effects of short sleep but not long sleep on both physical and mental QOL. In addition, the negative impact of specific types of sleep disturbance on depression may be greater than the impact of shortening of sleep duration.

Prevalence and Associated Factors of Nocturnal Eating Behavior and Sleep-Related Eating Disorder-Like Behavior in Japanese Young Adults: Results of an Internet Survey Using Munich Parasomnia Screening

Nocturnal (night) eating syndrome and sleep-related eating disorder have common characteristics, but are considered to differ in their level of consciousness during eating behavior and recallability. To date, there have been no large population-based studies determining their similarities and differences. We conducted a cross-sectional web-based survey for Japanese young adults aged 19-25 years to identify factors associated with nocturnal eating behavior and sleep-related eating disorder-like behavior using Munich Parasomnia Screening and logistic regression. Of the 3347 participants, 160 (4.8%) reported experiencing nocturnal eating behavior and 73 (2.2%) reported experiencing sleep-related eating disorder-like behavior. Smoking (p < 0.05), use of hypnotic medications (p < 0.01), and previous and/or current sleepwalking (p < 0.001) were associated with both nocturnal eating behavior and sleep-related eating disorder-like behavior. A delayed sleep-wake schedule (p < 0.05) and sleep disturbance (p < 0.01) were associated with nocturnal eating behavior but not with sleep-related eating disorder-like behavior. Both nocturnal eating behavior and sleep-related eating disorder-like behavior had features consistent with eating disorders or parasomnias. Nocturnal eating behavior but not sleep-related eating disorder-like behavior was characterized by a sleep-awake phase delay, perhaps representing an underlying pathophysiology of nocturnal eating syndrome.

Association of circadian properties of temporal processing with rapid antidepressant response to wake and light therapy in bipolar disorder

BACKGROUND

Temporal processing, crucial to guide behavior toward a goal, may have a role in forming a depressive episode, yet it remains unclear which properties of temporal processing are central to antidepressant response. Production of a short duration oscillates in a circadian manner. Altered circadian organization of physiology and behavior are a hallmark of bipolar disorder. We thus tested whether circadian dynamics of time production associate with treatment response in bipolar disorder.

METHODS

Over the three cycles of total sleep deprivation combined with light therapy (chronotherapeutics) in one week, 20 inpatients with a major depressive episode in the course of bipolar disorder produced 10 s and rated their subjective mood and vigilance levels repeatedly.

RESULTS

Eleven patients (58%) among 19 completers achieved remission. Produced time intervals (PTIs) fluctuated more synchronously with mood levels (r = -0.77) than vigilance levels (r = -0.59) during treatment. A higher degree of shortening of PTIs, but not changes in mood or vigilance levels, during the initial 24-h period of treatment predicted better response (LR χ² = 4.58, P = 0.032). Strong opposite daily changes for PTIs and mood levels observed at baseline were both attenuated after treatment only in remitters (F = 7.25, P = 0.015).

LIMITATIONS

Potential external confounders that affect time perception were not controlled.

CONCLUSIONS

The results are the first to demonstrate an association of the circadian properties of time perception with antidepressant effects of chronotherapeutics and suggest the potential utility of time production in predicting clinical outcome of bipolar depression.

Bright light exposure advances consolidation of motor skill accuracy in humans

Light has attracted increasing attention as a critical determinant of memory processing. While sleep selectively consolidates newly encoded memories according to their future relevance, the role of light in human memory consolidation is largely unknown. Here, we report how bright light (BL), provided during encoding, influences online and offline consolidation of motor skill learning. We sought to determine whether relatively slower and faster key-press transitions within individuals were differentially consolidated by BL. Healthy human subjects were briefly exposed to either BL (>8000 lx) or control light (CL; <500 lx) during memory encoding at 13:00 h, when light minimally affects circadian phase-shifting, and were retested 24 h later. The effects of BL on online and offline performance gains were determined by accuracy and speed. BL-exposed subjects showed better overall performance accuracy during training and lower overnight accuracy gains after a subsequent night of sleep than did CL-exposed subjects. BL preferentially improved the initially most difficult individual key-press transitions during practice; these were only improved overnight under CL. By contrast, accuracy during what had been the easiest key-press transitions at the beginning of the experiment was unaffected by light conditions or online/offline learning processes. BL effects were not observed for performance speed, mood, or sleep-wake patterns. Brief BL exposure during training may advance motor memory selection and consolidation that optimally meet individual requirements for potential gains, which would otherwise depend on post-training sleep. This suggests a new way of enhancing brain plasticity to compensate for impaired sleep-dependent memory consolidation in neuropsychiatric conditions.

Effects of bedtime periocular and posterior cervical cutaneous warming on sleep status in adult male subjects: a preliminary study

Appropriate warming of the periocular or posterior cervical skin has been reported to induce autonomic or mental relaxation in humans. To clarify the effects of cutaneous warming on human sleep, eight male subjects with mild sleep difficulties were asked to try three experimental conditions at home, each lasting for 5 days, in a cross-over manner: warming of the periocular skin with a warming device for 10 min before habitual bedtime, warming of the posterior cervical skin with a warming device for 30 min before habitual bedtime, and no treatment as a control. The warming device had a heat- and steam-generating sheet that allowed warming of the skin to 40 °C through a chemical reaction with iron. Electroencephalograms (EEGs) were recorded during nocturnal sleep using an ambulatory EEG device and subjected to spectral analysis. All the participants reported their sleep status using a visual analog scale. We found that warming of the periocular or posterior cervical skin significantly improved subjective sleep status relative to the control. The EEG delta power density in the first 90 min of the sleep episode was significantly increased under both warming of the periocular or posterior cervical skin relative to the control. These results suggest that warming of appropriate skin regions may have favorable effects on subjective and objective sleep quality.

Sleep-independent offline consolidation of response inhibition during the daytime post-training period

Appropriate inhibitory response control is associated with goal-directed behavior. Sleep accelerates the offline consolidation of acquired motor skills that are explicitly predictable; however, the effect of sleep on implicit (unpredictable) motor skills remains controversial. We speculated that a key component of response inhibition skill differentiates between these skill consolidation properties because explicit prediction can minimize the inhibitory efforts in a motor skill. We explored the offline skill learning properties of response inhibition during sleep and wakefulness using auditory Go and Go/Nogo tasks. We attempted to discriminate the possible effects of time elapsed after training (12 or 24 h), post-training sleep/wake state (sleep or wakefulness), and time of day (nighttime or daytime) in 79 healthy human subjects divided into 6 groups that underwent various sleep regimens prior to training and retesting. We found that delayed response inhibition skill improvement was achieved via a simple passage of daytime, regardless of the participants’ alertness level. Our results suggest that sleep-independent neuroplasticity occurs during the daytime and facilitates a delayed learning of response inhibition skill.