Differentiating nonrestorative sleep from nocturnal insomnia symptoms: demographic, clinical, inflammatory, and functional correlates

Nonrestorative sleep and its associated factors in Chinese adolescents and the moderation effects of coffee or tea consumption

BACKGROUND

Nonrestorative sleep (NRS) is related to numerous adverse outcomes. There is rare evidence of its associated factors, especially in Chinese adolescents. This study aimed to explore the factors associated with NRS in Chinese adolescents and the potential moderation effects of coffee or tea consumption.

METHODS

This cross-sectional study invited adolescents attending Grades 7-11 in Nanjing, China, to complete a self-administered questionnaire, including their NRS, stress, anxiety, physical symptoms, depression, sociodemographics, and lifestyles. Linear regressions were applied to investigate the associated factors of their NRS, with the moderation effects of coffee or tea consumption and other characteristics being tested by additionally including their interactions.

RESULTS

Totally 481 adolescents (49% male, age 15.5 ± 1.5 years) were enrolled, with the average global NRS score of 42.16 ± 7.57. Higher family income (β = 2.01, P = 0.007), longer sleep duration (β = 2.33, P = 0.011), and moderate after-class activity (β = 1.50, P = 0.044) contributed less NRS, while higher educational level (β = -2.60, P = 0.033), more coffee or tea consumption (β = -1.68, P = 0.013), physical symptoms (β = -3.85, P < 0.001), stress (β = -0.23, P = 0.005), anxiety (β = -1.54, P = 0.045), and depression (β = -0.13, P = 0.014) contributed more NRS. Females (β = 0.82, P = 0.005), older age (β = -0.46, P = 0.029), and higher education level (β = -1.68, P < 0.001) contributed less refreshment from sleep, more physical/medical symptoms of NRS, and less daytime function, respectively. Coffee or tea consumption moderated the associations of somatic symptoms (β = 0.25, P = 0.021), stress (β = 0.29, P = 0.022), anxiety (β = 0.27, P = 0.005), and depression (β = 0.17, P = 0.021) with NRS.

CONCLUSIONS

Longer sleep duration, moderate after-class activity, reduced coffee or tea consumption, and promotion of physical and mental health may help reduce adolescents' NRS. Coffee or tea consumption may help buffer the negative associations of somatic symptoms, stress, anxiety, and depression with NRS.

Quantifying the interrelationships between physical, social, and cognitive-emotional components of mental fitness using digital technology

Mental fitness is a construct that goes beyond a simple focus on subjective emotional wellbeing to encompass more broadly our ability to think, feel, and act to achieve what we want in our daily lives. The measurement and monitoring of multiple (often interacting) domains is crucial to gain a holistic and complete insight into an individual's mental fitness. We aimed to demonstrate the capability of a new mobile app to characterise the mental fitness of a general population of Australians and to quantify the interrelationships among different domains of mental fitness. Cross-sectional data were collected from 4901 adults from the general population of Australians engaged in work or education who used a mobile app (Innowell) between September 2021 and November 2022. Individuals completed a baseline questionnaire comprised of 26 questions across seven domains of mental fitness (i.e., physical activity, sleep and circadian rhythms, nutrition, substance use, daily activities, social connection, psychological distress). Network analysis was applied at both a domain-level (e.g., 7 nodes representing each cluster of items) and an individual item-level (i.e., 26 nodes representing all questionnaire items). Only 612 people (12%) were functioning well across all domains. One quarter (n = 1204, 25%) had only one problem domain and most (n = 3085, 63%) had multiple problem domains. The two most problematic domains were physical activity (n = 2631, 54%) and social connection (n = 2151, 44%), followed closely by daily activity (n = 1914, 39%). At the domain-level, the strongest association emerged between psychological distress and daily activity (r = 0.301). Psychological distress was the most central node in the network (as measured by strength and expected influence), followed closely by daily activity, sleep and circadian rhythms and then social connection. The item-level network revealed that the nodes with the highest centrality in the network were: hopelessness, depression, functional impairment, effortfulness, subjective energy, worthlessness, and social connectedness. Social connection, sleep and circadian rhythms, and daily activities may be critical targets for intervention due to their widespread associations in the overall network. While psychological distress was not among the most common problems, its centrality may indicate its importance for indicated prevention and early intervention. We showcase the capability of a new mobile app to monitor mental fitness and identify the interrelationships among multiple domains, which may help people develop more personalised insights and approaches.

Overtime work is related to nonrestorative sleep independently of short sleep time among a Japanese occupational population

OBJECTIVE

The symptoms of insomnia are defined as difficulty falling asleep, difficulty staying asleep, and early awakening. Although also a symptom of insomnia, nonrestorative sleep (NRS) is clearly more associated with objective indices than other insomnia symptoms. However, the link between NRS and overtime work duration is poorly understood.

METHODS

The results of a single year's medical examinations were investigated for 26,144 Japanese office workers who were 30 to 59 years old. NRS status and lifestyle were collected through a computer-assisted medical interview. The subjects were asked about the presence or absence of NRS and their lifestyles in the most recent two to three months. The subjects were asked about their sleep times and average overtime durations per month (< 20 h/month, ≥ 20 but < 40 h/month, ≥ 40 but < 60 h/month, and ≥ 60 h/month). The relationships between NRS and overtime work duration adjusted for sleep time were also analyzed.

RESULTS

The proportion of subjects with NRS showed a stepwise increase as overtime work hours increased. A logistic regression analysis was performed using NRS as an objective variable. The multivariate analysis demonstrated that overtime work duration (OR, 1.13; 95% CI 1.10-1.17; P < 0.001; per one-category increase) was an independent determinant of NRS.

CONCLUSION

For office workers, long hours of overtime work increased the NRS prevalence at any sleep duration.

Relationship between nonrestorative sleep and heartburn among a Japanese occupational population

BACKGROUND

Nonrestorative sleep (NRS) is a symptom of insomnia and is clearly more associated with objective indices than other insomnia symptoms. Gastroesophageal reflux disease (GERD) and insomnia are known to be strongly related. However, the link between NRS and heartburn, a main symptom of GERD, is poorly understood. Therefore, the relationships between them were investigated in addition to sleep duration.

METHODS

The results of a single year's medical examinations were investigated for 29,475 Japanese active office workers who were 20 to 59 years old. NRS and heartburn were investigated in a medical interview using a personal computer. The relationships between NRS and heartburn in addition to sleep duration were also analyzed.

RESULTS

The subjects were 46.6 ± 8.7 years old (mean ± SD) and 27% and 13% of them had NRS and heartburn, respectively. The presence of NRS together with a sleep duration of ≤ 5, 6, 7 or ≥ 8 hours was an independent comorbid factor for heartburn compared with the absence of NRS together with a sleep duration of seven hours (reference; odds ratio [OR], 2.38; 95% confidence interval [CI], 2.11-2.69, OR, 2.44; 95% CI, 2.16-2.76, OR, 2.33; 95% CI, 1.94-2.79; and OR, 1.72; 95% CI, 1.14-2.52). The absence of NRS together with a sleep duration of ≤ 5 hours was also an independent comorbid factor for heartburn compared with the reference (OR, 1.20; 95% CI, 1.05-1.37).

CONCLUSIONS

NRS in active workers may contribute to heartburn comorbidity despite the sleep duration as in other workers without NRS.

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.

Relationship between nonrestorative sleep with short sleep duration and diabetes mellitus comorbid among a Japanese occupational population

Objective

Nonrestorative sleep (NRS) is one of the symptoms of insomnia and is clearly more associated with objective indices, such as sleep stability, sleep fragmentation, and inflammatory responses, than other insomnia symptoms. However, the link between NRS and diabetes mellitus is poorly understood. Therefore, the prevalence of NRS in workers and the relationships between NRS and diabetes were investigated.

Methods

The results of a single year's medical examinations were investigated for 26,144 Japanese active office workers who were 30 to 59 years old. NRS was investigated using a personal computer in a medical interview. Furthermore, the relationships between NRS and diabetes comorbidity in addition to sleep duration were also analyzed.

Results

The mean age of the subjects was 47.9 ± 7.3 years old, and the proportion of subjects with NRS was 26%. The presence of NRS together with a sleep duration ≤ 5 h or a sleep duration of 6 h was an independent comorbid factor for diabetes compared with the absence of NRS together with a sleep duration of 7 h (odds ratio [OR] 1.34; 95% confidence interval [CI] 1.14-1.58; P < 0.001; and OR 1.25; 95% CI 1.04-1.48; P = 0.015).

Conclusion

NRS in active workers may contribute to the development of diabetes even if the workers have the same short sleep durations as other workers without NRS.

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.

Fear of Cancer Recurrence and Sleep in Couples Coping With Early-Stage Breast Cancer

BACKGROUND

Fear of cancer recurrence (FCR) and sleep disturbance are common in cancer survivors. Yet, little research has examined their relationship, and even less is known about what links may exist between these variables among the intimate partners of cancer survivors.

PURPOSE

This study examines the relationship between FCR and sleep disturbance in breast cancer survivors and their partners. Using daily sleep data collected at two distinct periods early in survivorship-the completion of adjuvant treatment and the first post-treatment mammogram-higher survivor and partner FCR was hypothesized to predict greater sleep disturbance.

METHODS

Breast cancer survivors and intimate partners (N = 76 couples; 152 individuals) each reported sleep duration, sleep quality, sleep onset latency, and wake after sleep onset each morning of two 21-day sleep diary bursts during the first year post-diagnosis. Three validated measures formed latent FCR factors for survivors and partners, which were used to predict average daily sleep.

RESULTS

Across both sleep diary bursts, survivor FCR was associated with their own reduced sleep duration, reduced sleep quality, and greater sleep onset latency. Survivor FCR was also associated with their partners' reduced sleep quality and greater sleep onset latency. Partner FCR was associated with their own reduced sleep duration, reduced sleep quality, and greater sleep onset latency. Partner FCR was also associated with survivors' reduced sleep quality.

CONCLUSIONS

Findings revealed intrapersonal and interpersonal associations between FCR and sleep disturbance, addressing gaps in knowledge on FCR and an outcome with known short- and long-term implications for health and mortality.

Mortality associated with nonrestorative short sleep or nonrestorative long time-in-bed in middle-aged and older adults

Associations of sleep duration with human health could differ depending on whether sleep is restorative. Using data from 5804 participants of the Sleep Heart Health Study, we examined the longitudinal association of sleep restfulness combined with polysomnography-measured total sleep time (TST) or time in bed (TIB), representing different sleeping behaviors, with all-cause mortality. Among middle-aged adults, compared with restful intermediate TST quartile, the lowest TST quartile with feeling unrested was associated with higher mortality (hazard ratio [HR], 1.54; 95% confidence interval [CI] 1.01–2.33); the highest TST quartile with feeling rested was associated with lower mortality (HR, 0.55; 95% CI 0.32–0.97). Among older adults, the highest TIB quartile with feeling unrested was associated with higher mortality, compared with restful intermediate TIB quartile (HR, 1.57; 95% CI 1.23–2.01). Results suggest a role of restorative sleep in differentiating the effects of sleep duration on health outcomes in midlife and beyond.

Effects of subjective-objective sleep discrepancy on the response to cognitive behavior therapy for insomnia

OBJECTIVE

This study aimed to evaluate the clinical correlates of sleep discrepancy and how subjective-objective sleep discrepancy (SD) affects the results of cognitive behavioral therapy for insomnia (CBT-I) in patients with insomnia disorder.

METHODS

A total of 33 patients aged >55 years with insomnia disorders participated in this prospective cohort study. Sleep discrepancy (SD) was defined as the difference between the sleep duration derived from the PSG and self-report questionnaires. SD > 2 h was classified as high SD. Self-report questionnaires, and polysomnography (PSG) were performed before 4 weeks of group CBT-I. Statistical analyses were performed to investigate the association of SD with baseline characteristics and CBT-I results, and compare intergroup difference of pre and post-treatment of high SD and low SD.

RESULTS

Patients in the high SD group reported poor subjective sleep, such as lower sleep quality, shorter sleep duration, longer sleep latency, and lower sleep efficiency. However, they had longer sleep duration, higher sleep efficiency in the PSG. There were 35% males in low SD group, but no males in high SD group. After 4 weeks of group CBT-I, SD was positively associated with the effect of CBT-I on subjective total sleep time (r = 0.499, p < 0.006) and sleep efficiency (r = 0.463, p = 0.01) after adjusting age, sex and apnea-hypopnea index.

CONCLUSION

The results of this study suggest that patients in the high SD group may respond better to CBT-I than those in lower SD group. Evaluation of SD may help clinicians to decide tailored treatment strategies for treating insomnia disorders.

Leisure-Time Physical Activity and General Health Mitigate Effects of Job Demands on Nonrestorative Sleep: CDC National Healthy Worksite Project

OBJECTIVE

We sought to determine if leisure-time physical activity (LTPA) modified the adverse relationship between high job demands and nonrestorative sleep (NRS).

METHODS

We conducted a multivariate logistic regression analysis among workers from the cross-sectional National Healthy Worksite Project (n = 4683) using self-report Likert-Scale data on psychological and physical demands of jobs, LTPA and general health in relation to NRS.

RESULTS

Not engaging in LTPA was associated with NRS for workers with jobs at the lowest or highest levels of the physical demand scale (OR 1.64, 95% CI: 0.96-2.81, OR 2.06, 95% CI: 0.95-4.45; respectively) in comparison to those who met LTPA recommendations. When assessing psychological demands, poor general health was associated with NRS at all levels of the scale independent of LTPA.

CONCLUSIONS

LTPA may reduce NRS for workers with jobs at either extreme of physical demands.

Bi-directional relationships between co-morbid insomnia and sleep apnea (COMISA)

Insomnia and obstructive sleep apnea (OSA) commonly co-occur. Approximately 30-50% of patients with OSA report clinically significant insomnia symptoms, and 30-40% of patients with chronic insomnia fulfil diagnostic criteria for OSA. Compared to either insomnia or OSA alone, co-morbid insomnia and sleep apnea (COMISA) is associated with greater morbidity for patients, complex diagnostic decisions for clinicians, and reduced response to otherwise effective treatment approaches. Potential bi-directional causal relationships between the mechanisms and manifestations of insomnia and OSA could play an integral role in the development and management of COMISA. A greater understanding of these relationships is required to guide personalized diagnostic and treatment approaches for COMISA. This review summarizes the available evidence of bi-directional relationships between COMISA, including epidemiological research, case studies, single-arm treatment studies, randomized controlled treatment trials, and objective sleep study data. This evidence is integrated into a conceptual model of COMISA to help refine the understanding of potential bi-directional causal relationships between the two disorders. This theoretical framework is essential to help guide future research, improve diagnostic tools, determine novel therapeutic targets, and guide tailored sequenced and multi-faceted treatment approaches for this common, complex, and debilitating condition.

Fluctuations in Self-Reported Symptoms Predict Objective Physical Activity in Adults With Type 2 Diabetes

PURPOSE

The purpose of this study was to examine the association between self-reported symptoms including fatigue and sleep disturbance with moderate-intensity physical activity among adults with type 2 diabetes.

METHODS

This report was a secondary analysis of a cross-sectional study. Data from 53 participants with at least 6 days of repeated measures were used. Daytime physical activity and energy expenditure were assessed using a wrist-worn accelerometer at the free-living setting. Fatigue upon awakening was measured using a 0 to 10 scale. Sleep (eg, restorative sleep, sleep duration, and sleep efficiency) was measured using the Consensus Sleep Diary for Morning. Data were analyzed using linear mixed models by including within- and between-person effects.

RESULTS

Participants were predominantly females (54.7%) with a mean age of 60.3 years. Controlling for the covariates, at the individual level (within-person), fluctuations in restorative sleep and fatigue upon awakening predicted moderate-intensity PA. Similarly, at the individual level, fluctuations in restorative sleep and fatigue upon awakening predicted average hourly energy expenditure. However, at the group level (between-person), no significant associations were found between fatigue and restorative sleep with moderate-intensity physical activity.

CONCLUSIONS

The study findings suggest that within-person fluctuations in fatigue and restorative sleep upon awakening predict daytime moderate-intensity physical activity. At the individual level, reducing fluctuations in fatigue and restorative sleep might encourage participation in physical activity. More research is warranted to uncover the underlying causes of fluctuations in fatigue and restorative sleep. Meanwhile, diabetes care and education specialists should pay attention to the within-person fluctuations of fatigue and sleep.

Noise sensitivity associated with nonrestorative sleep in Chinese adults: a cross-sectional study

Background

Nonrestorative sleep is a common sleep disorder with a prevalence ranging from 1.4 to 35%, and is associated with various psychological and physical health issues. Noise exposure and noise sensitivity have been proposed to contribute to nonrestorative sleep. This study aimed to examine the relationships among noise, noise sensitivity, nonrestorative sleep, and physiological sleep parameters in Chinese adults.

Methods

A cross-sectional household survey was conducted with randomly selected Chinese adults based on a frame stratified by geographical districts and types of quarters in Hong Kong. We administered a battery of questionnaires, including the Nonrestorative Sleep Scale, the Weinstein Noise Sensitivity Scale, the ENRICHD Social Support Instrument, the Patient Health Questionnaire, and the Perceived Stress Scale to assess nonrestorative sleep, noise sensitivity, social support, somatic symptoms and stress, respectively. Anxiety and depression were evaluated by the Hospital Anxiety and Depression Scale while sociodemographic and lifestyle characteristics were assessed with an investigator-developed sheet. Nocturnal noise level and physiological sleep parameters were measured during nighttime for a week by noise dosimetry and actigraphy, respectively. A structured multiphase linear regression was conducted to estimate associations.

Results

A total of 500 adults (66.4% female) with an average age of 39 years completed this study. Bivariate regressions showed that age, marital status, occupation, family income, season, exercise, cola and soda consumption, social support, somatic symptoms, stress, depression, noise sensitivity, total sleep time, and awakenings were associated with nonrestorative sleep. In the multivariable analysis, family income, season, exercise, social support, somatic symptoms, stress, and depression remained associated with nonrestorative sleep. Specifically, a one-unit increase of noise sensitivity was associated with 0.08 increase in nonrestorative sleep (95% confidence interval [CI]: 0.01, 0.15, p = 0.023). Nocturnal noise was negatively associated with time in bed (b = − 1.65, 95% CI: − 2.77, − 0.52, p = 0.004), total sleep time (b = − 1.61, 95% CI: − 2.59, − 0.62, p = 0.001), and awakenings (b = − 0.16, 95% CI: − 0.30, − 0.03, p = 0.018), but was not associated with nonrestorative sleep.

Conclusions

Nonrestorative sleep was predicted by noise sensitivity in addition to family income, season, exercise, social support, somatic symptoms, stress, and depression.

Longitudinal effects of nocturnal insomnia symptom subtypes and nonrestorative sleep on the incidence of depression among community-dwelling older adults: results from the Health and Retirement Study

OBJECTIVE

The relationships between different insomnia symptom subtypes and the onset of depression among older adults are inconsistent. It may be that each subtype has a distinct temporal effect on depression not easily captured by the different follow-up intervals used in past studies. We systemically investigated the temporal effects by examining the links between subtypes and the onset of depression at different follow-up intervals among community-dwelling older adults.

METHODS

We used the 2006 wave of the Health and Retirement Study as baseline (n = 9151). The outcome was the onset of depression at 2-year (2008 wave), 4-year (2010 wave), and 6-year (2012 wave) follow-ups. The independent variables were difficulty with falling asleep (initial insomnia), waking up during the night (middle insomnia), waking up too early and being unable to fall asleep again (late insomnia), and nonrestorative sleep at baseline. Factors known to be related to depression among older adults were included as covariates.

RESULTS

Our findings showed that each insomnia symptom subtype had distinct temporal effects on the onset of depression. It appeared that the effects of initial insomnia may take longer to emerge than indicated in previous studies. Middle insomnia and late insomnia had weak relationships with depression. Nonrestorative sleep predicted the onset of depression at every follow-up period.

CONCLUSIONS

We found that documenting the temporal effects of insomnia symptom subtypes helps both to classify individuals' insomnia symptoms and predict the onset of depression. We recommend taking temporal effects of insomnia symptom subtypes into account in future investigations and clinical practice.

Association between Non-Restorative Sleep and Quality of Life in Chinese Adolescents

To examine non-restorative sleep and its impact on quality of life (QOL) in Chinese adolescents, this cross-sectional study included 2827 students aged 12–20 who were selected from 15 secondary schools in Hong Kong, China. Non-restorative sleep was assessed by a single item, rated on a 0–10 scale: “To what extent did you feel refreshed upon awakening over the past month?”. QOL was evaluated by the World Health Organization Quality of Life Measure—Abbreviated Version Hong Kong Chinese Version. Univariable and multivariable linear mixed-effects regressions were conducted to examine the influence of non-restorative sleep (NRS) on QOL. In the present sample, the mean overall QOL was 13.83, and the extent of feeling refreshed upon awakening was 4.75 on average. In multivariable linear mixed-effects regression, one unit feeling less refreshed upon awakening was associated with 0.37 units of poorer overall QOL after adjusting for age, gender, medical conditions, parental education and occupation, weekly hours of aerobic exercises, smoking and drinking habits. Additionally, adolescents with a significantly poorer overall QOL were more likely to be older, have medical problems, have parents with an educational level of primary school or below, have an unemployed father, engage in less weekly aerobic exercise, and be current smokers or former drinkers. Adolescents who experienced non-restorative sleep had a poorer QOL. Future studies are needed to alleviate non-restorative sleep to improve health outcomes in adolescents.

Reciprocal relations between work stress and insomnia symptoms: A prospective study

Work stress and poor sleep are closely related in cross-sectional data, but evidence from prospective data is limited. We analysed how perceived stress and work stressors (work demands, decision authority and workplace social support) are related to key dimensions of insomnia over time, using structural equation modelling. Biennial measurements from a large sample of the working population in Sweden enabled us to analyse both the relationship from stress to sleep as well as that from sleep to stress. Overall, we found reciprocal relations between insomnia and all four stress measures. However, looking at the relation between each dimension of insomnia and each stress measure, there were some differences in direction of effects. In the direction from stress to sleep, all work stressors as well as perceived stress predicted both difficulties initiating sleep and difficulties maintaining sleep. The same was found for non-restorative sleep, with the exception for decision authority. In the opposite direction, difficulties maintaining sleep predicted increased levels of work demands and perceived stress. Difficulties initiating sleep stood out among the insomnia symptoms as not predicting any of the stress measures, while non-restorative sleep was the only symptom predicting all stress measures. The results advance the understanding of the stress-sleep relationship and indicate a potential vicious circle between insomnia and perceived stress as well as work stressors, suggesting that the workplace could be an arena for interventions to alleviate insomnia.

Insomnia symptoms and risk of cardiovascular diseases among 0.5 million adults: A 10-year cohort

OBJECTIVE

To examine the associations of individual insomnia symptoms with risks of incident cardio-cerebral vascular diseases (CVD) and possible moderating factors among Chinese adults.

METHODS

The China Kadoorie Biobank is a prospective cohort study that recruited participants from 10 areas across China. Data from 487,200 adults 30 to 79 years of age who were free of stroke, coronary heart disease, and cancer at baseline were analyzed. Three insomnia symptoms were assessed with self-reported difficulties in initiating or maintaining sleep, early morning awakening, and daytime dysfunction for at least 3 d/wk at baseline. Incidences of CVD were followed up through disease registries and national health insurance databases until 2016.

RESULTS

During a median of 9.6 years of follow-up, 130,032 cases of CVD were documented. Cox regressions showed that 3 insomnia symptoms were associated with increased risk of total CVD, with respective adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) of 1.09 (95% CI 1.07-1.11), 1.07 (95% CI 1.05-1.09), and 1.13 (95% CI 1.09-1.18). Participants with individual symptoms also had higher risks of ischemic heart disease (IHD; HR 1.13, 1.09, and 1.17) and ischemic stroke but not hemorrhagic stroke. Participants with all 3 symptoms were at an 18%, 22%, or 10% higher risk of CVD, IHD, or ischemic stroke compared to nonsymptomatic adults. Associations between 3 symptoms and CVD incidence were consistently stronger in younger adults or those without baseline hypertension (p for interaction <0.05).

CONCLUSIONS

Individual and coexisting insomnia symptoms are independent risk factors for CVD incidence, especially among young adults or adults who have not developed hypertension.

Insomnia and risk of mortality from all-cause, cardiovascular disease, and cancer: Systematic review and meta-analysis of prospective cohort studies

Growing evidence indicates that insomnia may be associated with mortality. However, these findings have been inconsistent. We systematically searched MEDLINE and EMBASE to identify prospective cohort studies that assessed the association between insomnia disorder/individual insomnia symptoms and the risk of mortality among adults aged ≥18 yrs. We addressed this association using summary hazard ratios (HRs) and 95% confidence intervals (CIs) calculated using random-effects meta-analysis, and the GRADE approach to rate the certainty of evidence. Twenty-nine cohorts including 1,598,628 individuals (55.3% men; mean age 63.7 yrs old) with a median follow-up duration of 10.5 yrs proved eligible. Difficulty falling asleep (DFA) and non-restorative sleep (NRS) were associated with an increased risk of all-cause mortality (DFA: HR = 1.13, 95%CI 1.03 to 1.23, p = 0.009, moderate certainty; NRS: HR = 1.23, 95%CI 1.07 to 1.42, p = 0.003, high certainty) and cardiovascular disease mortality (DFA: 1.20, 95%CI: 1.01, 1.43; p = 0.04, moderate certainty; NRS: HR = 1.48, 95%CI 1.06 to 2.06, p = 0.02, moderate certainty). Convincing associations between DFA and all-cause mortality were restricted to the mid to older-aged population (moderate credibility). Insomnia disorder, difficulty maintaining sleep, and early morning awakening proved to be unassociated with all-cause and cardiovascular disease mortality. No insomnia symptoms proved to be associated with cancer-related mortality.

The Sleep-Immune Crosstalk in Health and Disease

Sleep and immunity are bidirectionally linked. Immune system activation alters sleep, and sleep in turn affects the innate and adaptive arm of our body's defense system. Stimulation of the immune system by microbial challenges triggers an inflammatory response, which, depending on its magnitude and time course, can induce an increase in sleep duration and intensity, but also a disruption of sleep. Enhancement of sleep during an infection is assumed to feedback to the immune system to promote host defense. Indeed, sleep affects various immune parameters, is associated with a reduced infection risk, and can improve infection outcome and vaccination responses. The induction of a hormonal constellation that supports immune functions is one likely mechanism underlying the immune-supporting effects of sleep. In the absence of an infectious challenge, sleep appears to promote inflammatory homeostasis through effects on several inflammatory mediators, such as cytokines. This notion is supported by findings that prolonged sleep deficiency (e.g., short sleep duration, sleep disturbance) can lead to chronic, systemic low-grade inflammation and is associated with various diseases that have an inflammatory component, like diabetes, atherosclerosis, and neurodegeneration. Here, we review available data on this regulatory sleep-immune crosstalk, point out methodological challenges, and suggest questions open for future research.

Association of functioning and quality of life with objective and subjective measures of sleep and biological rhythms in major depressive and bipolar disorder

OBJECTIVE

Disruptions in biological rhythms and sleep are a core aspect of mood disorders, with sleep and rhythm changes frequently occurring prior to and during mood episodes. Wrist-worn actigraphs are increasingly utilized to measure ambulatory activity rhythm and sleep patterns.

METHODS

A comprehensive study using subjective and objective measures of sleep and biological rhythms was conducted in 111 participants (40 healthy volunteers [HC], 38 with major depressive disorder [MDD] and 33 with bipolar disorder [BD]). Participants completed 15-day actigraphy and first-morning urine samples to measure 6-sulfatoxymelatonin levels. Sleep and biological rhythm questionnaires were administered: Biological Rhythms Interview of Assessment in Neuropsychiatry (BRIAN), Munich Chronotype Questionnaire (MCTQ), Pittsburgh Sleep Quality Index (PSQI) and Epworth Sleepiness Scale (ESS). Actigraph data were analyzed for sleep and daily activity rhythms, light exposure and likelihood of transitioning between rest and activity states.

RESULTS

Mood groups had worse subjective sleep quality (PSQI) and biological rhythm disruption (BRIAN) and higher objective mean nighttime activity than controls. Participants with BD had longer total sleep time, higher circadian quotient and lower 6-sulfatoxymelatonin levels than HC group. The MDD group had longer sleep onset latency and higher daytime probability of transitioning from rest to activity than HCs. Mood groups displayed later mean timing of light exposure. Multiple linear regression analysis with BRIAN scores, circadian quotient, mean nighttime activity during rest and daytime probability of transitioning from activity to rest explained 43% of variance in quality-of-life scores. BRIAN scores, total sleep time and probability of transitioning from activity to rest explained 52% of variance in functioning (all p < 0.05).

CONCLUSIONS

Disruption in biological rhythms is associated with poorer functioning and quality of life in bipolar and MDD. Investigating biological rhythms and sleep using actigraphy variables, urinary 6-sulfatoxymelatonin and subjective measures provide evidence of widespread sleep and circadian system disruptions in mood disorders.

Associations of presence or absence of exercise and/or physical activity with non-restorative sleep by gender and age: a cross-sectional study

OBJECTIVES

Non-restorative sleep (NRS) is related to qualitative aspects of sleep. The associations of NRS with exercise (EX; a planned and purposeful activity) and physical activity (PA; daily bodily movement) by gender and age have not yet been clarified. We investigated the associations of EX and/or PA with NRS by gender and age.

DESIGN

A cross-sectional study.

SETTING

The data on gender, age, presence of NRS and engagement in EX and/or PA were obtained from database and questionnaire of specified medical check-ups in FY 2013 in Japan. The analysis was conducted in 2017.

PARTICIPANTS

The subjects comprised 90 122 residents (38 603 males and 51 519 females), aged 40-74 years, who had completed the specified medical check-ups.

OUTCOME MEASURE

The presence of NRS was assessed using a question asking whether or not the subjects usually got enough sleep. NRS was considered to be present when the subjects answered 'No'. Binary logistic regression analysis was used to assess the associations of presence or absence of EX and/or PA with NRS. The OR and 95% CI of NRS prevalence were calculated and compared between those engaged in both EX and PA and the others.

RESULTS

Except for 40s and 70s among males and 40s and 50s among females, the absence of EX or PA was associated with higher ORs of NRS than referent. ORs were more than twice compared with the referents in males in their 50s (OR 2.030(95% CI 1.675 to 2.459)) and 60s (OR 2.148(95% CI 1.970 to 2.343)) and females in their 60s (OR 2.142(95% CI 1.994 to 2.302)) when they engaged in neither EX nor PA.

CONCLUSIONS

Healthcare providers must take into account the similarities and differences in the associations of EX and/or PA with NRS by gender and age when they support people with NRS.

Sleep: A Pathway Linking Personality to Mortality Risk

Personality and sleep predict longevity; however, no investigation has tested whether sleep mediates this association. Thus, we tested this effect across a 20-year follow-up (N = 3,759) in the Midlife Development in the United States cohort (baseline M _age = 47.15) using proportional hazards in a structural equation modeling framework. Lower conscientiousness predicted increased death risk via the direct, indirect, and total effect of quadratic sleep duration. Although there were no other direct personality-mortality effects, higher neuroticism and agreeableness and lower conscientiousness predicted increased death risk via the joint indirect effects of quadratic sleep duration and higher daytime dysfunction. Lower extraversion predicted increased mortality risk via the indirect effect of daytime dysfunction. Our findings have implications for personality-based health interventions.

Sleep Disturbances and Inflammatory Biomarkers in Schizophrenia: Focus on Sex Differences

OBJECTIVES

Persons with schizophrenia, and women in particular, are at high risk for sleep disturbances and inflammatory activation. The sleep-inflammation link has been reported to be stronger in women within the general population. This study sought to examine the sleep-inflammation link in persons with schizophrenia and its relationship with demographic, clinical and cognitive variables.

DESIGN

Cross-sectional case-control study.

PARTICIPANTS

Community-dwelling outpatients with schizophrenia (N=144, 46% women) and non-psychiatric comparison (NC) participants (N=134, 52% women), age 26-65 years.

MEASUREMENTS

Reported sleep disturbances (sleep quality and duration), and mental and physical health were assessed. Cognitive assessments included executive functioning (Delis-Kaplan Executive Function System) and global cognitive functioning (Telephone Interview for Cognitive Status - modified.) Inflammatory biomarkers included pro-inflammatory cytokines [high sensitivity C-Reactive Protein (hs-CRP), Interleukin (IL)-6, Tumor Necrosis Factor-α (TNF-α)] and an anti-inflammatory cytokine (IL-10).

RESULTS

The schizophrenia group had longer sleep duration, worse sleep quality, and increased levels of hs-CRP, IL-6, and TNF-α compared to NCs. Women with schizophrenia were less likely to have good sleep quality and had elevated levels of hs-CRP and IL-6 compared to men with schizophrenia. In the schizophrenia group, worse sleep quality and global cognitive functioning were associated with higher hs-CRP and IL-6 levels. Female sex and younger age were also associated with higher hs-CRP levels.

CONCLUSIONS

Sleep disturbances and increased inflammation, which were common in schizophrenia, were associated in persons with schizophrenia. Moreover, women with schizophrenia had worse sleep quality and inflammation than men. Further examination of the sleep-inflammation links, their contribution to clinical outcomes, and sex-specific factors is warranted.

Study protocol and rationale for a prospective, randomized, double-blind, placebo-controlled study to evaluate the effects of Ashwagandha (Withania somnifera) extract on nonrestorative sleep

Nonrestorative sleep (NRS) is one of the cardinal symptoms of insomnia and can occur independent of other components of insomnia. Among the sleep disturbances, NRS has been little studied in the general population, even though this symptom plays an important role in several medical conditions associated with chronic inflammation such as heart disease, fibromyalgia, and chronic fatigue syndrome, as well as various sleep disorders. There is paucity in the literature about effective treatments for NRS. Ashwagandha (Withania somnifera) has been demonstrated to reduce anxiety and stress, allowing the body to settle down and prepare for sleep. This study will be a double-blind, randomized, placebo-controlled interventional study in NRS population.The NRS participants are identified using Restorative Sleep Questionnaire-weekly version (RSQ-W) questionnaire. Actigraphy and polysomnography are used for the objective assessment of sleep. The other assessments used are Hamilton Anxiety Depression Scale (HADS), World Health Organization Quality of Life (WHOQOL) scales, and C-reactive protein. Routine blood and urine analyses will be conducted to assess the safety of treatment. Duration of study for each participant will be 50 days with "day one" for screening followed by randomization for the treatment. The duration for medicine/placebo intake shall be 42 days.Primary outcome will be to evaluate effect of daily supplement of ashwagandha extract compared with placebo in subjects with NRS at 6 weeks from baseline, as assessed by the total score of RSQ-W.

CTRI REGISTRATION NUMBER

CTRI/2017/02/007801.

Psychiatric Symptoms in Patients Receiving Dolutegravir

INTRODUCTION

Psychiatric symptoms (PSs) are reported to occur frequently in people living with HIV and may be associated with specific antiretrovirals. We analyzed PSs observed with dolutegravir (DTG) and other frequently prescribed anchor drugs.

METHODS

Selected PSs (insomnia, anxiety, depression, and suicidality) occurring in HIV-positive patients during DTG treatment across 5 randomized clinical trials (3 double-blind), in the Observational Pharmaco-Epidemiology Research & Analysis (OPERA) cohort, and among cases spontaneously reported to ViiV Healthcare were analyzed.

RESULTS

In clinical trials, PSs were reported at low and similar rates in patients receiving DTG or comparators [atazanavir, darunavir, efavirenz, or raltegravir (RAL)]. Insomnia was most commonly reported. The highest rates were observed in SINGLE (DTG 17%, efavirenz 12%), with consistently lower rates in the other trials (DTG: 3%-8% versus comparator: 3%-7%). More efavirenz-treated patients withdrew because of PSs than patients treated with other anchor drugs. In OPERA, history of PSs at baseline was lowest in efavirenz-treated patients compared with patients treated with DTG, RAL, or darunavir. Despite baseline differences, prevalence and incidence during treatment were similar across the 4 anchor drugs. Withdrawal rates for PSs were lowest for DTG (0%-0.6%) and highest for RAL (0%-2.5%). Spontaneously reported events were similar in nature to clinical trial data.

CONCLUSIONS

Analysis of 3 different data sources shows that, similar to other frequently prescribed anchor drugs to treat HIV infection, PSs are also reported in DTG-treated patients. These events are reported with low frequency and rarely necessitate DTG discontinuation.

Sex and age differences in the associations between sleep behaviors and all-cause mortality in older adults: results from the National Health and Nutrition Examination Surveys

OBJECTIVE

Our aim was to examine sex- and age-specific relationships of sleep behaviors with all-cause mortality rates.

METHODS

A retrospective cohort study was conducted among 5288 adults (≥50 years) from the 2005-2008 National Health and Nutrition Examination Surveys who were followed-up for 54.9 ± 1.2 months. Sleep duration was categorized as < 7 h, 7-8 h and >8 h. Two sleep quality indices were generated through factor analyses. 'Help-seeking behavior for sleep problems' and 'diagnosis with sleep disorders' were defined as yes/no questions. Sociodemographic covariates-adjusted Cox regression models were applied to estimate hazard ratios (HRs) and 95% confidence intervals (CIs).

RESULTS

A positive relationship was observed between long sleep and all-cause mortality rate in the overall sample (HR = 1.90, 95% CI: 1.38, 2.60), among males (HR = 1.48, 95% CI: 1.05, 2.09), females (HR = 2.32, 95% CI: 1.48, 3.61) and elderly (≥65 years) people (HR = 1.80, 95% CI: 1.30, 2.50). 'Sleepiness/sleep disturbance' (Factor I) and all-cause mortality rate were positively associated among males (HR = 1.22, 95% CI: 1.03, 1.45), whereas 'poor sleep-related daytime dysfunction' (Factor II) and all-cause mortality (HR = 0.75, 95% CI: 0.62, 0.91) were negatively associated among elderly people.

CONCLUSIONS

Sex- and age-specific relationships were observed between all-cause mortality rate and specific sleep behaviors among older adults.

Sleep Difficulties and Insomnia Symptoms in Norwegian Musicians Compared to the General Population and Workforce

Sleep problems are reported as common among performing artists and musicians. However, epidemiological research comparing musicians to different groups of the general population is lacking. For this study, 4,168 members of the Norwegian Musician's Union were invited to an online survey regarding work and health. Of the 2,121 (51%) respondents, 1,607 were active performing musicians. We measured prevalence of insomnia symptoms using the Bergen Insomnia Scale (BIS), and compared this sample to a representative sample of the general Norwegian population (n = 2,645). Overall, musicians had higher prevalence of insomnia symptoms compared to the general population (Prevalence Difference 6.9, 95% Confidence Interval 3.9-10.0). Item response analysis showed that this difference was mainly explained by nonrestorative sleep and dissatisfaction with sleep among musicians. An additional analysis, comparing musicians to the general Norwegian workforce (n = 8,518) on sleep difficulties, confirmed this tendency (Prevalence Difference 6.2, 95% Confidence Interval 4.3-8.1). Musicians performing classical, contemporary, rock, and country music reported the highest prevalence of insomnia, and these genres might be of special interest when developing preventative measures, treatment strategies, and further research on sleep difficulties among musicians.

Validation of the Chinese Version of the Functional Outcomes of Sleep Questionnaire-10 in Pregnant Women

We evaluated the psychometric properties of a Mandarin Chinese version of the Functional Outcomes of Sleep Questionnaire-10 (FOSQ-10) in pregnant women. A total of 228 first-trimester pregnant women participated in the study, which was conducted in an outpatient obstetric clinic at a medical center in Taipei, Taiwan. The Chinese version of the FOSQ-10 demonstrated satisfactory internal consistency (Cronbach alpha = .85), adequate corrected item-total correlations (from .40 to .67), and acceptable test-retest reliability over 7 days (ICC = .73). Construct validity was supported by exploratory factor analysis showing a one-factor structure with item loadings between .49 and .77. Significant associations with the Medical Outcomes Study Short-Form Health Survey 12 version 2 and Pittsburgh Sleep Quality Index supported criterion-related and convergent validity. Significant differences in the Chinese version of the FOSQ-10 total scores were found between women with clinically significant daytime sleepiness and those without, suggesting adequate discriminant validity. Ceiling effects were observed for all items, but no floor or ceiling effects were found for total scores. Findings suggest that the Chinese version of the FOSQ-10 is a valid and reliable instrument to identify important effects of sleep-related impairment in Chinese women during pregnancy. Further testing is needed in more diverse pregnant women, such as women with complicated pregnancies and those with sleep disorders. © 2016 Wiley Periodicals, Inc.

Sleep Disturbance, Sleep Duration, and Inflammation: A Systematic Review and Meta-Analysis of Cohort Studies and Experimental Sleep Deprivation

BACKGROUND

Sleep disturbance is associated with inflammatory disease risk and all-cause mortality. Here, we assess global evidence linking sleep disturbance, sleep duration, and inflammation in adult humans.

METHODS

A systematic search of English language publications was performed, with inclusion of primary research articles that characterized sleep disturbance and/or sleep duration or performed experimental sleep deprivation and assessed inflammation by levels of circulating markers. Effect sizes (ES) and 95% confidence intervals (CI) were extracted and pooled using a random effect model.

RESULTS

A total of 72 studies (n > 50,000) were analyzed with assessment of C-reactive protein (CRP), interleukin-6 (IL-6), and tumor necrosis factor α (TNFα). Sleep disturbance was associated with higher levels of CRP (ES .12; 95% CI = .05-.19) and IL-6 (ES .20; 95% CI = .08-.31). Shorter sleep duration, but not the extreme of short sleep, was associated with higher levels of CRP (ES .09; 95% CI = .01-.17) but not IL-6 (ES .03; 95% CI: -.09 to .14). The extreme of long sleep duration was associated with higher levels of CRP (ES .17; 95% CI = .01-.34) and IL-6 (ES .11; 95% CI = .02-20). Neither sleep disturbances nor sleep duration was associated with TNFα. Neither experimental sleep deprivation nor sleep restriction was associated with CRP, IL-6, or TNFα. Some heterogeneity among studies was found, but there was no evidence of publication bias.

CONCLUSIONS

Sleep disturbance and long sleep duration, but not short sleep duration, are associated with increases in markers of systemic inflammation.

The Neurological Sleep Index: A suite of new sleep scales for multiple sclerosis

Objective

The objective of this study was to develop patient-reported outcome measures for sleep dysfunction and sleepiness in multiple sclerosis (MS), since there are currently no MS-specific measurement tools for these clinically important entities.

Methods

Items were generated from semi-structured interviews followed by cognitive debrief. A 42-item pool was administered to patients with MS at three neuroscience centres in the UK. Comparator scales were co-administered. Constructs were validated by Rasch analysis, guided by initial exploratory factor analysis.

Results

There were two supraordinate qualitative themes of diurnal sleepiness and non-restorative nocturnal sleep. Rasch analysis on 722 records produced three scales, which corresponded to diurnal sleepiness, non-restorative nocturnal sleep and fragmented nocturnal sleep. All had excellent fit parameters, were unidimensional and were free from differential item functioning. A summed raw score cut-point of 31/48 in the Diurnal Sleepiness Scale equated to the standard cut-point of 10 on the Epworth Sleepiness Scale (ESS).

Conclusion

Three high-quality measurement scales were developed, and together they compose the Neurological Sleep Index for MS (NSI-MS). The Diurnal Sleepiness Scale might provide an alternative to the ESS. The Non-Restorative Nocturnal Sleep Scale and the Fragmented Nocturnal Sleep Scale appear to be the only such measures for use in MS.

Insomnia and Telomere Length in Older Adults

STUDY OBJECTIVES

Insomnia, particularly in later life, may raise the risk for chronic diseases of aging and mortality through its effect on cellular aging. The current study examines the effects of insomnia on telomere length, a measure of cellular aging, and tests whether insomnia interacts with chronological age to increase cellular aging.

METHODS

A total of 126 males and females (60-88 y) were assessed for insomnia using the Diagnostic and Statistical Manual IV criterion for primary insomnia and the International Classification of Sleep Disorders, Second Edition for general insomnia (45 insomnia cases; 81 controls). Telomere length in peripheral blood mononuclear cells (PBMC) was determined using real-time quantitative polymerase chain reaction (qPCR) methodology.

RESULTS

In the analysis of covariance model adjusting for body mass index and sex, age (60-69 y versus 70-88 y) and insomnia diagnosis interacted to predict shorter PBMC telomere length (P = 0.04). In the oldest age group (70-88 y), PBMC telomere length was significantly shorter in those with insomnia, mean (standard deviation) M(SD) = 0.59(0.2) compared to controls with no insomnia M(SD) = 0.78(0.4), P = 0.04. In the adults aged 60-69 y, PBMC telomere length was not different between insomnia cases and controls, P = 0.44.

CONCLUSIONS

Insomnia is associated with shorter PBMC telomere length in adults aged 70-88 y, but not in those younger than 70 y, suggesting that clinically severe sleep disturbances may increase cellular aging, especially in the later years of life. These findings highlight insomnia as a vulnerability factor in later life, with implications for risk for diseases of aging.

Bisphenol-A and Sleep Adequacy among Adults in the National Health and Nutrition Examination Surveys

STUDY OBJECTIVES

To evaluate bisphenol-A (BPA) level and its relationship to sleep adequacy in a nationally representative sample of U.S. adults.

METHODS

A population-based cross-sectional study was conducted using 2005-2010 National Health and Nutrition Examination Survey whereby data were collected using in-person interviews, physical examination and laboratory testing. BPA level was measured in urine samples and analyzed as loge-transformed variable and in quartiles (< 0.9 ng/mL; 0.9 to < 1.9 ng/mL; 1.9 to < 3.7 ng/mL; 3.7+ ng/mL). Sleep adequacy was operationalized with three questions: "How much sleep do you usually get at night on weekdays or workdays?", "Have you ever told a doctor or other health professionals that you have trouble sleeping?" and "Have you ever been told by a doctor or other health professional that you have a sleep disorder?" Sleep duration was further categorized as (< 6 h, ≥ 6 h); (< 7 h, 7-8 h, > 8 h); (< 5 h, 5-6 h, 7-8 h, ≥ 9 h). Linear, binary, and ordinal logistic regression models were constructed.

RESULTS

Loge-transformed BPA level was inversely related to sleep duration defined, in hours, as a continuous variable, a dichotomous variable (≥ 6, < 6), or an ordinal variable (≥ 9, 7-8, 5-6, < 5), after adjustment for confounders. Help-seeking behavior for sleep problems and diagnosis with sleep disorders were not significantly associated with loge-transformed BPA level in fully adjusted models.

CONCLUSIONS

Loge-transformed BPA level may be associated with fewer hours of sleep among U.S. adults, with implications for prevention. Further research involving diverse populations are needed to confirm these study findings.

Delayed sleep phase: An important circadian subtype of sleep disturbance in bipolar disorders

BACKGROUND

Theoretical models of Bipolar Disorder (BD) highlight that sleep disturbances may be a marker of underlying circadian dysregulation. However, few studies of sleep in BD have reported on the most prevalent circadian sleep abnormality, namely Delayed Sleep Phase (DSP).

METHODS

A cross-sectional study of 404 adults with BD who met published clinical criteria for insomnia, hypersomnia or DSP, and who had previously participated in a study of sleep in BD using a comprehensive structured interview assessment.

RESULTS

About 10% of BD cases with a sleep problem met criteria for a DSP profile. The DSP group was younger and had a higher mean Body Mass Index (BMI) than the other groups. Also, DSP cases were significantly more likely to be prescribed mood stabilizers and antidepressant than insomnia cases. An exploratory analysis of selected symptom item ratings indicated that DSP was significantly more likely to be associated with impaired energy and activity levels.

LIMITATIONS

The cross-sectional design precludes examination of longitudinal changes. DSP is identified by sleep profile, not by diagnostic criteria or objective sleep records such as actigraphy. The study uses data from a previous study to identify and examine the DSP group.

CONCLUSIONS

The DSP group identified in this study can be differentiated from hypersomnia and insomnia groups on the basis of clinical and demographic features. The association of DSP with younger age, higher BMI and impaired energy and activity also suggest that this clinical profile may be a good proxy for underlying circadian dysregulation.

Neural Reward Processing Mediates the Relationship between Insomnia Symptoms and Depression in Adolescence

STUDY OBJECTIVES

Emerging evidence suggests that insomnia may disrupt reward-related brain function-a potentially important factor in the development of depressive disorder. Adolescence may be a period during which such disruption is especially problematic given the rise in the incidence of insomnia and ongoing development of neural systems that support reward processing. The present study uses longitudinal data to test the hypothesis that disruption of neural reward processing is a mechanism by which insomnia symptoms-including nocturnal insomnia symptoms (NIS) and nonrestorative sleep (NRS)-contribute to depressive symptoms in adolescent girls.

METHOD

Participants were 123 adolescent girls and their caregivers from an ongoing longitudinal study of precursors to depression across adolescent development. NIS and NRS were assessed annually from ages 9 to 13 years. Girls completed a monetary reward task during a functional MRI scan at age 16 years. Depressive symptoms were assessed at ages 16 and 17 years. Multivariable regression tested the prospective associations between NIS and NRS, neural response during reward anticipation, and the mean number of depressive symptoms (omitting sleep problems).

RESULTS

NRS, but not NIS, during early adolescence was positively associated with late adolescent dorsal medial prefrontal cortex (dmPFC) response to reward anticipation and depressive symptoms. DMPFC response mediated the relationship between early adolescent NRS and late adolescent depressive symptoms.

CONCLUSIONS

These results suggest that NRS may contribute to depression by disrupting reward processing via altered activity in a region of prefrontal cortex involved in affective control. The results also support the mechanistic differentiation of NIS and NRS.

Development of the National Healthy Sleep Awareness Project Sleep Health Surveillance Questions

OBJECTIVES

For the first time ever, as emphasized by inclusion in the Healthy People 2020 goals, sleep health is an emphasis of national health aims. The National Healthy Sleep Awareness Project (NHSAP) was tasked to propose questions for inclusion in the next Behavioral Risk Factor Surveillance System (BRFSS), a survey that includes a number of questions that target behaviors thought to impact health, as a means to measure community sleep health. The total number of questions could not exceed five, and had to include an assessment of the risk for obstructive sleep apnea (OSA).

METHODS

An appointed workgroup met via teleconference and face-to-face venues to develop an inventory of published survey questions being used to identify sleep health, to develop a framework on which to analyze the strengths and weaknesses of current survey questions concerning sleep, and to develop recommendations for sleep health and disease surveillance questions going forward.

RESULTS

The recommendation was to focus on certain existing BRFSS questions pertaining to sleep duration, quality, satisfaction, daytime alertness, and to add to these other BRFSS existing questions to make a modified STOP-BANG questionnaire (minus the N for neck circumference) to assess for risk of OSA.

CONCLUSIONS

Sleep health is an important dimension of health that has previously received less attention in national health surveys. We believe that 5 questions recommended for the upcoming BRFSS question banks will assist as important measures of sleep health, and may help to evaluate the effectiveness of interventions to improve sleep health in our nation.

Sleep loss activates cellular inflammation and signal transducer and activator of transcription (STAT) family proteins in humans

Sleep disturbance and short sleep duration are associated with inflammation and related disorders including cardiovascular disease, arthritis, diabetes mellitus, and certain cancers. This study was undertaken to test the effects of experimental sleep loss on spontaneous cellular inflammation and activation of signal transducer and activator of transcription (STAT) family proteins, which together promote an inflammatory microenvironment. In 24 healthy adults (16 females; 8 males), spontaneous production of IL-6 and TNF-α in monocytes and spontaneous intranuclear expression of activated STAT1, STAT3, and STAT5 in peripheral blood mononuclear cells (PBMC), monocyte-, and lymphocyte populations were measured in the morning after uninterrupted baseline sleep, partial sleep deprivation (PSD, sleep period from 3a.m. to 7a.m.), and recovery sleep. Relative to baseline, spontaneous monocytic expression of IL-6 and TNF-α was significantly greater after PSD (P<0.02) and after recovery sleep (P<0.01). Relative to baseline, spontaneous monocytic expression of activated STAT1 and STAT5 was significantly greater after recovery sleep (P<0.007 and P<0.02, respectively) but not STAT3 (P=0.09). No changes in STAT1, STAT3, or STAT5 were found in lymphocyte populations. Sleep loss induces activation of spontaneous cellular innate immunity and of STAT family proteins, which together map the dynamics of sleep loss on the molecular signaling pathways that regulate inflammatory and other immune responses. Treatments that target short sleep duration have the potential to constrain inflammation and reduce the risk for inflammatory disorders and some cancers in humans.

Association of Markers of Inflammation with Sleep and Physical Activity Among People Living with HIV or AIDS

This study examined associations of sleep and minutes spent in moderate-vigorous physical activity (MVPA) with C-reactive protein (CRP) and interleukin (IL)-6 among persons living with HIV. Cross-sectional analyses (n = 45) focused on associations of inflammatory outcomes (i.e., CRP and IL-6) with actigraph-derived sleep duration, latency, and efficiency; sleep onset; wake time; and wake-after-sleep-onset; as well as MVPA. Least square means for CRP and IL-6 by levels of sleep and MVPA were computed from general linear models. Individuals below the median of sleep duration, above the median for sleep onset, and below the median of MVPA minutes had higher CRP or IL-6 levels. Generally, individuals with both low MVPA and poor sleep characteristics had higher inflammation levels than those with more MVPA and worse sleep. Understanding the combined impact of multiple lifestyle/behavioral factors on inflammation could inform intervention strategies to reduce inflammation and therefore, chronic disease risk.

Sleep disturbance and longitudinal risk of inflammation: Moderating influences of social integration and social isolation in the Coronary Artery Risk Development in Young Adults (CARDIA) study

Both sleep disturbance and social isolation increase the risk for morbidity and mortality. Systemic inflammation is suspected as a potential mechanism of these associations. However, the complex relationships between sleep disturbance, social isolation, and inflammation have not been examined in a population-based longitudinal study. This study examined the longitudinal association between sleep disturbance and systemic inflammation, and the moderating effects of social isolation on this association. The CARDIA study is a population-based longitudinal study conducted in four US cities. Sleep disturbance - i.e., insomnia complaints and short sleep duration - was assessed in 2962 African-American and White adults at baseline (2000-2001, ages 33-45years). Circulating C-reactive protein (CRP) was measured at baseline and follow-up (2005-2006). Interleukin-6 (IL-6) and subjective and objective social isolation (i.e., feelings of social isolation and social network size) were measured at follow-up. Sleep disturbance was a significant predictor of inflammation five years later after full adjustment for covariates (adjusted betas: 0.048, P=0.012 for CRP; 0.047, P=0.017 for IL-6). Further adjustment for baseline CRP revealed that sleep disturbance also impacted the longitudinal change in CRP levels over five years (adjusted beta: 0.044, P=0.013). Subjective social isolation was a significant moderator of this association between sleep disturbance and CRP (adjusted beta 0.131, P=0.002). Sleep disturbance was associated with heightened systemic inflammation in a general population over a five-year follow-up, and this association was significantly stronger in those who reported feelings of social isolation. Clinical interventions targeting sleep disturbances may be a potential avenue for reducing inflammation, particularly in individuals who feel socially isolated.

Persistent insomnia is associated with mortality risk

BACKGROUND

Insomnia has been associated with mortality risk, but whether this association is different in subjects with persistent vs intermittent insomnia is unclear. Additionally, the role of systemic inflammation in such an association is unknown.

METHODS

We used data from a community-based cohort to determine whether persistent or intermittent insomnia, defined based on persistence of symptoms over a 6-year period, was associated with death during the following 20 years of follow-up. We also determined whether changes in serum C-reactive protein (CRP) levels measured over 2 decades between study initiation and insomnia determination were different for the persistent, intermittent, and never insomnia groups. The results were adjusted for confounders such as age, sex, body mass index, smoking, physical activity, alcohol, and sedatives.

RESULTS

Of the 1409 adult participants, 249 (18%) had intermittent and 128 (9%) had persistent insomnia. During a 20-year follow-up period, 318 participants died (118 due to cardiopulmonary disease). In adjusted Cox proportional-hazards models, participants with persistent insomnia (adjusted hazards ratio [HR] 1.58; 95% confidence interval [CI], 1.02-2.45) but not intermittent insomnia (HR 1.22; 95% CI, 0.86-1.74) were more likely to die than participants without insomnia. Serum CRP levels were higher and increased at a steeper rate in subjects with persistent insomnia as compared with intermittent (P = .04) or never (P = .004) insomnia. Although CRP levels were themselves associated with increased mortality (adjusted HR 1.36; 95% CI, 1.01-1.82; P = .04), adjustment for CRP levels did not notably change the association between persistent insomnia and mortality.

CONCLUSIONS

In a population-based cohort, persistent, and not intermittent, insomnia was associated with increased risk for all-cause and cardiopulmonary mortality and was associated with a steeper increase in inflammation.

Cross-cultural and comparative epidemiology of insomnia: the Diagnostic and statistical manual (DSM), International classification of diseases (ICD) and International classification of sleep disorders (ICSD)

OBJECTIVE

To compare the prevalence of insomnia according to symptoms, quantitative criteria, and Diagnostic and Statistical Manual of Mental Disorders, 4th and 5th Edition (DSM-IV and DSM-5), International Classification of Diseases, 10th Revision (ICD-10), and International Classification of Sleep Disorders, 2nd Edition (ICSD-2), and to compare the prevalence of insomnia disorder between Hong Kong and the United States by adopting a similar methodology used by the America Insomnia Survey (AIS).

METHODS

Population-based epidemiological survey respondents (n = 2011) completed the Brief Insomnia Questionnaire (BIQ), a validated scale generating DSM-IV, DSM-5, ICD-10, and ICSD-2 insomnia disorder.

RESULTS

The weighted prevalence of difficulty falling asleep, difficulty staying asleep, waking up too early, and non-restorative sleep that occurred ≥3 days per week was 14.0%, 28.3%, 32.1%, and 39.9%, respectively. When quantitative criteria were included, the prevalence dropped the most from 39.9% to 8.4% for non-restorative sleep, and the least from 14.0% to 12.9% for difficulty falling asleep. The weighted prevalence of DSM-IV, ICD-10, ICSD-2, and any of the three insomnia disorders was 22.1%, 4.7%, 15.1%, and 22.1%, respectively; for DSM-5 insomnia disorder, it was 10.8%.

CONCLUSION

Compared with 22.1%, 3.9%, and 14.7% for DSM-IV, ICD-10, and ICSD-2 in the AIS, cross-cultural difference in the prevalence of insomnia disorder is less than what is expected. The prevalence is reduced by half from DSM-IV to DSM-5. ICD-10 insomnia disorder has the lowest prevalence, perhaps because excessive concern and preoccupation, one of its diagnostic criteria, is not always present in people with insomnia.

Insomnia symptoms and risk for unintentional fatal injuries--the HUNT Study

STUDY OBJECTIVES

To assess the association between insomnia symptoms and risk of fatal unintentional injuries.

DESIGN

Population-based prospective cohort study with a mean follow-up of 14 y, linking health survey data with information on insomnia symptoms to the National Cause of Death Registry.

SETTING

Nord-Trøndelag County, Norway.

PARTICIPANTS

A total of 54,399 men and women 20-89 y of age who participated in the Nord-Trøndelag Health Study between 1995 and 1997.

INTERVENTIONS

N/A.

MEASUREMENTS AND RESULTS

There were 277 unintentional fatal injuries, including 57 fatal motor vehicle injuries during follow-up. There was a dose-dependent association between the number of insomnia symptoms and risk of unintentional fatal injuries (P for trend 0.001) and fatal motor vehicle injuries (P for trend 0.023), respectively. The proportion of unintentional fatal injuries cases that could have been prevented in the absence of difficulties initiating sleep, difficulties maintaining sleep, and having a feeling of nonrestorative sleep were 8%, 9%, and 8%, respectively. The corresponding estimates for motor vehicle injuries were 34%, 11%, and 10%.

CONCLUSION

Insomnia is a major contributor to both unintentional fatal injuries in general as well as fatal motor vehicle injuries. Increasing public health awareness about insomnia and identifying persons with insomnia may be important in preventing unintentional fatal injuries.

The impact of poor sleep on cognition and activities of daily living after traumatic brain injury: a review

BACKGROUND/AIM

Patients frequently report sleep disruptions or insomnia during their hospital stay, particularly after a traumatic brain injury (TBI). The consequences of these sleep disturbances on everyday activities are not well documented and are therefore not considered in the evaluation of independence in activities of daily living (ADLs). The goal of this narrative review is to explore the consequences of poor sleep quality on cognition and ADLs in the acute and subacute stages of a moderate and severe TBI, when patients are in acute care or inpatient rehabilitation.

METHODS

We will present an overview of normal sleep and its role in cognitive functioning, and then present the findings of studies that have investigated sleep characteristics in hospital settings and the consequences of sleep disturbances on ADLs.

RESULTS

During hospitalisation, TBI patients present severe sleep disturbances such as insomnia and sleep fragmentation, which are probably influenced by both the medical condition and the hospital or rehabilitation environment. Sleep disruption is associated with several cognitive deficits, including attention, memory and executive function impairments. Poor quality and/or insufficient quantity of sleep in acute TBI probably affect general functioning and ADLs calling for these cognitive functions.

CONCLUSIONS AND SIGNIFICANCE

The cognitive impairments present following TBI are probably exacerbated by poor sleep quality and sleep deprivation during hospitalisation, which in turn impact ADLs among this population. Health-care personnel should further consider sleep disturbances among people with TBI and a sleep protocol should be established.

Association between combined lifestyle factors and non-restorative sleep in Japan: a cross-sectional study based on a Japanese health database

BACKGROUND

Although lifestyle factors such as cigarette smoking, excessive drinking, obesity, low or no exercise, and unhealthy dietary habits have each been associated with inadequate sleep, little is known about their combined effect. The aim of this study was to quantify the overall impact of lifestyle-related factors on non-restorative sleep in the general Japanese population.

METHODS AND FINDINGS

A cross-sectional study of 243,767 participants (men, 39.8%) was performed using the Specific Health Check and Guidance System in Japan. A healthy lifestyle score was calculated by adding up the number of low-risk lifestyle factors for each participant. Low risk was defined as (1) not smoking, (2) body mass index<25 kg/m², (3) moderate or less alcohol consumption, (4) regular exercise, and (5) better eating patterns. Logistic regression analysis was used to examine the relationship between the score and the prevalence of non-restorative sleep, which was determined from questionnaire responses. Among 97,062 men (mean age, 63.9 years) and 146,705 women (mean age, 63.7 years), 18,678 (19.2%) and 38,539 (26.3%) reported non-restorative sleep, respectively. The prevalence of non-restorative sleep decreased with age for both sexes. Compared to participants with a healthy lifestyle score of 5 (most healthy), those with a score of 0 (least healthy) had a higher prevalence of non-restorative sleep (odds ratio, 1.59 [95% confidence interval, 1.29-1.97] for men and 2.88 [1.74-4.76] for women), independently of hypertension, hypercholesterolemia, diabetes, and chronic kidney disease. The main limitation of the study was the cross-sectional design, which limited causal inferences for the identified associations.

CONCLUSIONS

A combination of several unhealthy lifestyle factors was associated with non-restorative sleep among the general Japanese population. Further studies are needed to establish whether general lifestyle modification improves restorative sleep.

Cognitive behavioral therapy vs. Tai Chi for late life insomnia and inflammatory risk: a randomized controlled comparative efficacy trial

STUDY OBJECTIVES

To investigate the comparative efficacy of cognitive behavioral therapy (CBT), Tai Chi Chih (TCC), and sleep seminar education control (SS) on the primary outcome of insomnia diagnosis, and secondary outcomes of sleep quality, fatigue, depressive symptoms, and inflammation in older adults with insomnia.

DESIGN

Randomized controlled, comparative efficacy trial.

SETTING

Los Angeles community.

PATIENTS

123 older adults with chronic and primary insomnia.

INTERVENTIONS

Random assignment to CBT, TCC, or SS for 2-hour group sessions weekly over 4 months with follow-up at 7 and 16 months.

MEASUREMENTS

Insomnia diagnosis, patient-reported outcomes, polysomnography (PSG), and high-sensitivity C-reactive protein (CRP) levels.

RESULTS

CBT performed better than TCC and SS in remission of clinical insomnia as ascertained by a clinician (P < 0.01), and also showed greater and more sustained improvement in sleep quality, sleep parameters, fatigue, and depressive symptoms than TCC and SS (all P values < 0.01). As compared to SS, CBT was associated with a reduced risk of high CRP levels (> 3.0 mg/L) at 16 months (odds ratio [OR], 0.26 [95% CI, 0.07-0.97] P < 0.05). Remission of insomnia was associated with lower levels of CRP (P < 0.05) at 16 months. TCC was associated with improvements in sleep quality, fatigue, and depressive symptoms as compared to SS (all P's < 0.05), but not insomnia remission. PSG measures did not change.

CONCLUSIONS

Treatment of late-life insomnia is better achieved and sustained by cognitive behavioral therapies. Insomnia treatment and remission reduces a marker of inflammatory risk, which has implications for cardiovascular morbidity and diabetes observed with sleep disturbance in epidemiologic surveys.