Psychometric evaluation and normative data for the Karolinska Sleep Questionnaire

Exploring sleepiness and stress among London bus drivers: An on-road observational study

Bus driver sleepiness is commonplace but often goes unreported within the industry. Whilst past research has begun to shed a light on the prevalence, potential causes, and consequences of bus driver sleepiness, this is often done using self-report methods. This is the first study to investigate sleepiness amongst city bus drivers on-road using a live bus route with drivers' regular schedules. A total of 16 participants completed two drives of their regular bus route once during an early morning shift and once during a daytime shift whilst physiological and self-report measures of sleep and stress were taken. Prior to these drives, drivers recorded their sleep in a diary and wore an actigraph to obtain objective sleep measures. Results showed that most drivers did not obtain sufficient sleep prior to early morning shifts, and often did not obtain as much sleep as they would need in order to feel rested before work. Sleepiness and stress were observed in both shifts. During early morning shifts sleepiness was likely a result of working during circadian lows and not obtaining enough sleep prior to the shift. In contrast, sleepiness during the daytime shift was likely a result of completing a highly demanding task in complex traffic which not only contributed to fatigue, but also led to increased levels of stress. As well as demonstrating the prevalence of sleepiness amongst bus drivers, these findings show that the causes of sleepiness can be multifaceted and often come about due to a combination of work and personal factors. In addition, the experience of sleepiness is not the same for all drivers, with individual differences in the experience of sleepiness playing a large role. These differences highlight the need for individualised interventions which should be considered by policymakers alongside the combination of causal factors within a larger systems approach.

Nocturnal hypoglycemia is associated with next day cognitive performance in adults with type 1 diabetes: Pilot data from the GluCog study

OBJECTIVE

 Individuals with type 1 diabetes (T1D) have increased risk for cognitive dysfunction and high rates of sleep disturbance. Despite associations between glycemia and cognitive performance using cross-sectional and experimental methods few studies have evaluated this relationship in a naturalistic setting, or the impact of nocturnal versus daytime hypoglycemia. Ecological Momentary Assessment (EMA) may provide insight into the dynamic associations between cognition, affective, and physiological states. The current study couples EMA data with continuous glucose monitoring (CGM) to examine the within-person impact of nocturnal glycemia on next day cognitive performance in adults with T1D. Due to high rates of sleep disturbance and emotional distress in people with T1D, the potential impacts of sleep characteristics and negative affect were also evaluated.

METHODS

 This pilot study utilized EMA in 18 adults with T1D to examine the impact of glycemic excursions, measured using CGM, on cognitive performance, measured via mobile cognitive assessment using the TestMyBrain platform. Multilevel modeling was used to test the within-person effects of nocturnal hypoglycemia and hyperglycemia on next day cognition.

RESULTS

 Results indicated that increases in nocturnal hypoglycemia were associated with slower next day processing speed. This association was not significantly attenuated by negative affect, sleepiness, or sleep quality.

CONCLUSIONS

 These results, while preliminary due to small sample size, showcase the power of intensive longitudinal designs using ambulatory cognitive assessment to uncover novel determinants of cognitive fluctuation in real world settings, an approach that may be utilized in other populations. Findings suggest reducing nocturnal hypoglycemia may improve cognition in adults with T1D.

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

OBJECTIVES

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

METHOD

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

RESULTS

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

CONCLUSIONS

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

Self-rated health and its bidirectional relationship with burnout, sleep quality and somatic symptoms in a general adult population

The aim of this study was to investigate how self-rated health (SRH) reflects ongoing ill-health and how SRH is associated with previous ill-health and/or predicts future ill-health such as burnout, disturbed sleep, and somatic symptoms. The study used two waves from the population-based Västerbotten Environmental and Health Study in which 2 336 adult persons participated by answering a questionnaire at two time points three years apart. Hierarchical and logistic regression analyses were conducted, thus treating all variables both continuously (degree) and categorically (case). The analyses were performed both cross-sectionally and longitudinally. The results showed bidirectionality between suboptimal SRH and burnout, disturbed sleep and somatic severity caseness. Moreover, degree of poor SRH was more likely to occur simultaneously to high degrees of burnout and somatic severity than to degree of poor sleep quality. Also, caseness of burnout, disturbed sleep and somatic severity increased the risk of simultaneous suboptimal SRH. Finally, the results showed that degree of burnout three years earlier, predicted degree of poor SRH, and that degree of poor SRH predicted degree of sleep three years later. In conclusion, in a population-based, normal adult sample there is a bidirectional relationship between suboptimal SRH and caseness of burnout, disturbed sleep quality and somatic symptoms, but not between degree of these symptoms. The results can have implications for health care meeting patients complaining about poor general health.

Sleep profiles of different psychiatric traits

Disturbed sleep comes in many forms. While the key role of sleep in mental health is undisputed, our understanding of the type of sleeping problems that manifest in the early stages of psychiatric disorders is limited. A sample without psychiatric diagnoses (N = 440, 341 women, 97 men, 2 non-binaries; Mage = 32.1, SD = 9.4, range 18-77) underwent a comprehensive assessment, evaluating eight sleep features and 13 questionnaires on common psychiatric complaints. Results revealed that traits of affect disorders, generalized anxiety, and ADHD had the worst sleep profiles, while autism disorder, eating disorder, and impulsivity traits showed milder sleep issues. Mania was the only trait associated with an overall better sleep profile. Across traits, insomnia and fatigue dominated and sleep variability was least prominent. These findings provide support for both transdiagnostic and disorder-specific targets for prevention and treatment.

Changes in Sleep Quality, Sleep Duration, and Sickness Absence: A Longitudinal Study with Repeated Measures

BACKGROUND

Sickness absence has been linked to short and long, as well as poor, sleep in a few studies. Such studies have started from a baseline measurement and followed up on subsequent sickness absence. In the present study, however, we focused on the change in biennial reports of sickness absence and sleep measures (using work-related variables as possible modifiers). We also searched for an interaction between predictors and gender since women report more sleep problems.

METHODS

A total of 5377 individuals (random sample from the Swedish working population) participated across five biennial points of measurement. Data were analyzed using mixed-model logistic regression.

RESULTS

The multivariable analysis of variation across the five time points showed that the significant sleep-related predictors of sickness absence (at least one occurrence during the preceding year) were sleep duration during days off (OR = 1.16, 95% Cl = 1.08;1.24) and sleep problems (OR = 1.42, 95% CI = 1.33;1.51). These also remained significant after the addition of psychosocial work factors. Sensitivity analyses indicated that a 9 h sleep duration during days off may represent a critical level in terms of increased sickness absence and that late rising contributed to the association between sickness absence and long sleep duration during days off. Women reported a higher sickness absence than men (OR = 2.16, 95% CI = 1.74;2.68) and had a higher probability of sickness absence for long sleep during days off and during the workweek than men.

CONCLUSIONS

It was concluded that increases in sleep problems and sleep duration during days off are longitudinally associated with changes in sickness absence and that women have a closer link between the two. This suggests that treatment for sleep problems may reduce the risk of sickness absence.

Return to Work Trajectories of Swedish Employees on Sick-Leave Due to Common Mental Disorders

OBJECTIVES

Recent research has emphasized that return to work (RTW) is a dynamic, gradual and often uneven process with a great degree of individual variation. This study aimed to identify RTW trajectories of Swedish employees on sick-leave due to common mental disorders (CMDs). The second aim was to explore which demographic, employment, health-related and work environment characteristics predicted RTW trajectory membership.

METHODS

Data comes from two 2-armed cluster-randomized controlled trials (RCT) with a 12-month follow-up. A participative problem-solving intervention aimed to reduce sick-leave was compared to care as usual (CAU) involving any kind of work-directed interventions. Participants on sick-leave due to CMDs at baseline (N = 197) formed the study sample. Latent growth mixture modeling and logistic regression were the main analytical approaches.

RESULTS

Five distinct RTW trajectories of Swedish employees were identified: Early RTW (N = 65), Delayed RTW (N = 50), Late RTW (N = 39), Struggling RTW (N = 21) and No RTW (N = 22). RTW trajectories differed consistently with regard to previous sick-leave duration and social support at work. More unique predictors of RTW trajectories included gender, rewards at work, work performance impairment due to health problems, home-to-work interference and stress-related exhaustion disorder.

CONCLUSION

The study may have important clinical implications for identifying patients belonging to a particular RTW trajectory. Knowledge on the modifiable work environment factors that differentiated between the RTW trajectories could be useful for designing effective workplace interventions, tailored to particular needs of employees with CMDs. However, in a first step, the results need to be replicated.

Tracked and self-reported nighttime smartphone use, general health, and healthcare utilization: results from the SmartSleep Study

STUDY OBJECTIVES

Nighttime smartphone use is an increasing public health concern. We investigated whether nighttime smartphone use is associated with general health and primary healthcare utilization.

METHODS

Four thousand five hundred and twenty individuals (age 35.6 ± 9.7 years, 35% male) provided self-reported information on smartphone use frequency, symptoms of depression, and general health (one-item perceived health and cross-symptom composite score). A subset of the study sample (n = 3221) tracked their nighttime smartphone use. Primary healthcare utilization, i.e. the number of weeks in which at least one service from the patient's general practitioner (GP) was billed in 2020, was extracted from Danish population registries. Statistical analysis comprised logistic and multiple linear regression, controlling for sociodemographics.

RESULTS

Three hundred and nineteen individuals (7%) reported using their smartphone almost every night or more. More frequent self-reported nighttime smartphone use was associated with poor general health across all measures. Using the smartphone almost every night or more was associated with 2.8 [95% CI: 1.9, 4.1] fold higher odds of reporting poor health and with an average of 1.4 [95% CI: 0.7, 2.1] additional GP utilizations per year compared to no use. Associations were also found for the cross-symptom composite score across all symptoms. Further adjustment for symptoms of depression attenuated some associations. Smartphone use towards the end of the sleep period (sleep-offset use) was associated with poorer self-reported general health, but not with healthcare utilization.

CONCLUSIONS

Nighttime smartphone use frequency is associated with poor general health and healthcare utilization. Further studies should investigate the underlying causal structure and nighttime smartphone use as a transdiagnostic intervention target.

Validation of Trøndelag Apnoea Score Proxy for Obstructive Sleep Apnoea in the General Population of Norway: The HUNT Study

The aim was to validate a new seven-item "TASC" (Trøndelag Apnoea Score) proxy for obstructive sleep apnoea (OSA) against polysomnography in the general population. Objectives included validation against different polysomnographic criteria, stratification by age and gender, and estimation of OSA prevalence. From the fourth wave of the Trøndelag Health Study (HUNT4), 1,201 participants were randomly invited to a substudy focusing on sleep and headaches, of whom 232 accepted and 84 (64% women, mean age 55.0 years, and standard deviation 11.5 years) underwent polysomnography. The TASC proxy sums seven binary items for snoring, observed breathing pauses, restricted daytime activities, hypertension, body mass index (≥30 kg/m2), age (≥50 years), and gender (male). A single night of ambulatory (home) polysomnography was analysed using both the recommended and optional hypopnoea criteria of the American Academy of Sleep Medicine (AASM). We found 65% sensitivity and 87% specificity (Cohen's κ = 0.53, 95% confidence interval 0.34-0.72) for TASC ≥ 3 against AHI ≥ 15 (recommended AASM criteria). Validity was similar against AHI ≥ 30 but lower against AHI ≥ 5 and against the optional AASM criteria. Sensitivity and overall validity were higher among men and those above 50 years of age. The prevalence of an apnoea-hypopnoea index (AHI) of at least 5, 15, or 30 using the recommended (and optional) AASM criteria was 73% (46%), 37% (18%), or 15% (5%). A seven-item TASC proxy for OSA showed good validity and may be useful in screening and epidemiological settings. Sensitivity, specificity, and validity vary considerably by cut-off, by polysomnographic scoring criteria, and by gender and age strata.

Anxiety, Sleep Problems, and Vigorous Physical Activity: Bidirectional Associations from Early Adolescence to Early Adulthood in Swedish Adolescents

Anxiety symptoms and sleep problems typically emerge during adolescence and are frequently intertwined. However, there is a dearth of knowledge concerning their reciprocal influence and whether physical activity might play a protective role in this relationship. The present study aims at filling this gap exploring also the moderating role of sex. 915 13-year-old Swedish adolescents (56% girls) answered a survey conducted four times: at ages 13 (T1), 16 (T2), 19 (T3), and 22 (T4). A random intercept cross-lagged panel model was used. At within-levels, sleep problems and anxiety symptoms had a bidirectional positive association in middle adolescence. Vigorous physical activity and anxiety symptoms showed a reciprocal negative association from middle adolescence. Vigorous physical activity and sleep problems were reciprocally associated only in late adolescence. Associations were the same for girls and boys. This study demonstrated that the relations between anxiety symptoms, sleep problems, and vigorous physical activity cannot be understood without adopting a developmental perspective and that middle adolescence is a crucial period to plan interventions to reduce anxiety symptoms and sleep problems.

Olfactory dysfunction as an early predictor for post-COVID condition at 1-year follow-up

BACKGROUND

Olfactory dysfunction together with neurological and cognitive symptoms are common after COVID-19. We aimed to study whether performance on olfactory and neuropsychological tests following infection predict post-COVID condition (PCC), persisting symptoms, and reduced health-related quality of life.

METHODS

Both hospitalized (N = 10) and non-hospitalized individuals (N = 56) were enrolled in this prospective cohort study. Participants were evaluated 1-3 months after infection with an olfactory threshold test and neuropsychological tests, which was used as predictors of PCC. A questionnaire outlining persisting symptoms and the validated instrument EuroQol five-dimension five-level for health-related quality of life assessment were used as outcome data 1 year after infection (N = 59). Principal component analysis was used to identify relevant predictors for PCC at 1 year.

RESULTS

Objectively assessed olfactory dysfunction at 1-3 months post infection, but not subjective olfactory symptoms, predicted post-COVID condition with reduced health-related quality of life (PCC+) at 1 year. The PCC+ group scored more often below the cut off for mild cognitive impairment on the Montreal Cognitive Assessment (61.5% vs. 21.7%) and higher on the Multidimensional Fatigue Inventory-20, compared to the group without PCC+.

CONCLUSION

Our results indicate that objectively assessed, olfactory dysfunction is a predictor for PCC+. These findings underscore the importance of objective olfactory testing. We propose that olfactory screening in the early post-acute phase of COVID-19 infection might identify individuals that are at higher risk of developing long-term health sequalae.

Study on the effect of human sympathetic nerve cold stimulation to relieve driving fatigue based on order recurrence plot

Driving fatigue is very likely to cause traffic accidents, seriously threatening the lives and properties of drivers. Therefore, accurate detection and effective mitigation of driving fatigue are crucial for ensuring the personal safety of drivers. This study proposes a method to relieve driving fatigue by properly reducing the temperature to stimulate the human sympathetic nerve. The method uses the intelligent cooling and blowing device on the car seat cushion to achieve cold stimulation of the sympathetic nerve of the driver by reducing the temperature of the driver's hip, back and neck, so as to increase the excitement of the sympathetic nerve, keep the driver alert and achieve the purpose of fighting driving fatigue. In view of the fact that the traditional fatigue detection method is easily affected by environmental factors and individual differences, this study uses the order recurrence plot (ORP) method to detect driving fatigue based on electroencephalogram (EEG) signals. The results show that ORP textures drawn by EEG signals of the two driving conditions (normal driving condition and sensory cold stimulation driving condition) are significantly different, and the quantization parameters determinism (DET) and average diagonal line length (DLL) values are significantly different. Cold stimulation of the subjects' hips, back and neck to alleviate driving fatigue was the best when the temperature was 21 °C. In addition, compared with the traditional methods of fatigue relief, the sensory cold stimulation method proposed in this study does not easily to produce tolerance and has no damage to the body.

Predictors of early adulthood insomnia following exposure to a single mass violence attack during adolescence: 7-13 year follow-up from the Utøya and HUNT studies

Background: The long-term impact of mass violence attacks is practically unknown, especially in children and adolescents. In a previous study, we found that 8.5 years after a terror attack targeting mainly adolescents, nearly half of the survivors met diagnostic criteria for insomnia.Objectives: The aims of this study were to investigate: (1) whether exposure to a single mass violence event during adolescence increases the risk of insomnia almost a decade later above that expected for a non-exposed population; and (2) whether prior interpersonal violence exposure and early post-traumatic reactions predict later insomnia.Method: Participants were survivors of the 2011 Utøya Island terrorist attack (n = 279) and controls from the HUNT Norwegian general population study (n = 35,664). Early adulthood insomnia was assessed using four items from the Karolinska Sleep Questionnaire 8.5 years after the attack. Participants who had also completed earlier data collection waves for both studies (n = 116 and 2382, respectively) were included in logistic regression models testing the associations between predictors during adolescence and later insomnia.Results: Nearly a decade after the Utøya attack, 38.4% (n = 56) of the survivors reported symptoms of insomnia indicative of probable insomnia compared to 20.5% (n = 5771) of controls. Terror exposure during adolescence was a significant predictor of later insomnia [odds ratio (OR) = 3.18, 95% confidence interval (CI) = 2.05-4.87, p < .001]. Early post-trauma symptoms of anxiety and depression (OR = 1.34, 95% CI = 1.02-1.76, p = .033) and weekly headaches (OR = 1.64, 95% CI = 1.08-2.47, p = .018) were also significant predictors while controlling for background factors and other predictors.Conclusion: Long-term assessment and treatment are needed for survivors of mass violence to improve resilience and recovery.

Revised Temperament and Character Inventory factors predict neuropsychiatric symptoms and aging-related cognitive decline across 25 years

Introduction

Personality traits and neuropsychiatric symptoms such as neuroticism and depression share genetic overlap and have both been identified as risks factors for development of aging-related neurocognitive decline and Alzheimer's disease (AD). This study aimed to examine revised personality factors derived from the Temperament and Character Inventory, previously shown to be associated with psychiatric disorders, as predictors of neuropsychiatric, cognitive, and brain trajectories of participants from a population-based aging study.

Methods

Mixed-effect linear regression analyses were conducted on data for the full sample (Nmax = 1,286), and a healthy subsample not converting to AD-dementia during 25-year follow-up (Nmax = 1,145), complemented with Cox proportional regression models to determine risk factors for conversion to clinical AD.

Results

Two personality factors, Closeness to Experience (CE: avoidance of new stimuli, high anxiety, pessimistic anticipation, low reward seeking) and Tendence to Liabilities (TL: inability to change, low autonomy, unaware of the value of their existence) were associated with higher levels of depressive symptoms, stress (CE), sleep disturbance (TL), as well as greater decline in memory, vocabulary and verbal fluency in the full sample. Higher CE was additionally associated with greater memory decline across 25 years in the healthy subsample, and faster right hippocampal volume reduction across 8 years in a neuroimaging subsample (N = 216). Most, but not all, personality-cognition associations persisted after controlling for diabetes, hypertension and cardiovascular disease. Concerning risks for conversion to AD, higher age, and APOE-ε4, but none of the personality measures, were significant predictors.

Conclusion

The results indicate that personality traits associated with psychiatric symptoms predict accelerated age-related neurocognitive declines even in the absence of neurodegenerative disease. The attenuation of some personality effects on cognition after adjustment for health indicators suggests that those effects may be partly mediated by somatic health. Taken together, the results further emphasize the importance of personality traits in neurocognitive aging and underscore the need for an integrative (biopsychosocial) perspective of normal and pathological age-related cognitive decline.

Estimation bias and agreement limits between two common self-report methods of habitual sleep duration in epidemiological surveys

Accurate measurement of habitual sleep duration (HSD) is crucial for understanding the relationship between sleep and health. This study aimed to assess the bias and agreement limits between two commonly used short HSD self-report methods, considering sleep quality (SQ) and social jetlag (SJL) as potential predictors of bias. Data from 10,268 participants in the International COVID Sleep Study-II (ICOSS-II) were used. Method-Self and Method-MCTQ were compared. Method-Self involved a single question about average nightly sleep duration (HSDself), while Method-MCTQ estimated HSD from reported sleep times on workdays (HSDMCTQwork) and free days (HSDMCTQfree). Sleep quality was evaluated using a Likert scale and the Insomnia Severity Index (ISI) to explore its influence on estimation bias. HSDself was on average 42.41 ± 67.42 min lower than HSDMCTQweek, with an agreement range within ± 133 min. The bias and agreement range between methods increased with poorer SQ. HSDMCTQwork showed less bias and better agreement with HSDself compared to HSDMCTQfree. Sleep duration irregularity was - 43.35 ± 78.26 min on average. Subjective sleep quality predicted a significant proportion of variance in HSDself and estimation bias. The two methods showed very poor agreement and a significant systematic bias, both worsening with poorer SQ. Method-MCTQ considered sleep intervals without adjusting for SQ issues such as wakefulness after sleep onset but accounted for sleep irregularity and sleeping in on free days, while Method-Self reflected respondents' interpretation of their sleep, focusing on their sleep on workdays. Including an SQ-related question in surveys may help bidirectionally adjust the possible bias and enhance the accuracy of sleep-health studies.

Daylight during winters and symptoms of depression and sleep problems: A within-individual analysis

BACKGROUND

With climate change Northern areas of the globe are expected to have less daylight during winters due to less snow and more cloudiness. While wintertime has been linked to mental health problems, the role of wintertime daylight has been scarcely studied. We examined longitudinal associations for wintertime objective exposure to global radiation and self-reported daylight exposure with symptoms of depression and sleep problems.

METHODS

Our analytical sample included 15,619 respondents from three Swedish Longitudinal Occupational Surveys of Health (2012, 2014 and 2016). Objective exposure was global radiation (MJ/m2, November-January and November-February). Subjective exposure was based on self-reported time spent outdoors in daylight (<1 h vs. ≥ 1 h, November-January). Symptoms of depression were evaluated using a six-item subscale of the (Hopkins) Symptom Checklist. Fixed-effects method with conditional logistic regression controlled for time-invariant participant characteristics by design and time-varying covariates were added into models.

RESULTS

One unit increase in the four-month averaged global radiation was associated with lower odds of depressive symptoms (OR 0.69, 95 % CI 0.52-0.91). These findings were confirmed using four-month cumulative exposure (OR 0.91, 95 % CI 0.85-0.98). Individuals reporting ≥ 1 h exposure to daylight during winter months were less likely to report depressive symptoms (OR 0.72, 95 % CI 0.60-0.82) compared to time when their exposure was < 1 h. Higher three-month exposure to global radiation suggested a protective association for sleep problems.

CONCLUSION

These findings suggest that higher exposure to daylight during winters may contribute to lower likelihood of depression symptoms.

Changes in pain, daily occupations, lifestyle, and health following an occupational therapy lifestyle intervention: a secondary analysis from a feasibility study in patients with chronic high-impact pain

OBJECTIVES

This study explored changes in pain-related parameters, occupational function, occupational balance, lifestyle factors, and self-perceived health status in adults with chronic high-impact pain participating in an occupational therapy lifestyle intervention.

METHODS

This one-group longitudinal feasibility study was performed in three continuous feasibility rounds. The occupational therapists-led intervention targeted meaningful occupations, regular physical activity, and a healthy diet. The intervention contained individual and group sessions and was added to the standard multidisciplinary chronic pain treatment. Outpatients (n=40, 85 % females, 46.6 ± 10.9 years old) participated in the study between April 2019 and December 2021. The analysis includes data for 31 participants. Analysis of pre-post changes assessed after each feasibility round were performed for the outcomes: pain intensity, pain sensitivity and pain modulation (pressure pain threshold and tolerance, temporal summation of pain and conditioned pain modulation), pain self-efficacy, pain catastrophizing, motor and process skills, occupational balance, daily wake-time movement, daily walking steps, body mass index, waist circumference, blood pressure, and self-perceived health status.

RESULTS

Improvements in motor skills (assessment of motor and process skills score=0.20 (1.37; 1.57), 95 % CI 0.01; 0.38) and temporal summation of pain (-1.19 (2.86; -1.67), 95 % CI -2.16; -0.22), but a decrease in pain tolerance (-7.110 (54.42; 47.32), 95 % CI -13.99; -0.22) were observed. Correlation analysis suggested moderate-to-very strong statistically significant relationships in several outcomes related to pain, health, pain coping, occupational balance, occupational functioning, body anthropometrics, and pain sensitivity.

CONCLUSIONS

This study suggested that the lifestyle intervention would benefit motor skills while effects on other outcomes were unclear in adults with chronic pain. To confirm the findings, a randomized trial evaluating effectiveness is needed. Ethical committee number: SJ-307 Reg. Clinicaltrials.gov: NCT03903900.

Associations between sleep habits, quality, chronotype and depression in a large cross-sectional sample of Swedish adolescents

OBJECTIVE

To investigate behavioral sleep habits, self-perceived quality of sleep, and chronotype, and to examine their association with clinically relevant levels of depression in Swedish adolescents.

METHOD

Questionnaire data were obtained from a representative sample of Swedish adolescents (n = 8449; 50.8% girls; aged 12-16). Depression was defined as >13 BDI-II scores. Logistic regression modelling estimated the effects of sleep duration, sleep quality, and chronotype on depression, adjusted for socio-demographic factors.

RESULTS

On weekdays, approximately 46% of adolescents slept less than the recommended length of eight hours per night (depressed: 68%, non-depressed: 40%). On weekends, however, only 17% slept shorter than recommended. Short weekday sleep duration was more common among girls than boys (53% vs. 38%) and girls reported worse sleep quality. The regression model showed that depression was predicted by weekday sleep duration (OR = 0.773, p < .0001), sleep quality (OR = 0.327, p < .0001), and late chronotype (OR = 1.126, p = .0017), but not by weekend sleep duration. A 30-minute increase in weekday sleep duration was associated with about 10% lower odds of depression.

CONCLUSIONS

A substantial proportion of Swedish adolescents do not seem to meet the sleep recommendations of eight hours per night. Short sleep duration on weekdays, poor sleep quality, and late chronotype were associated with increased risk of depression. Interventions promoting longer weekday sleep duration (e.g., later school start times) seem relevant in this context, but further research is needed to investigate the directionality and underlying mechanisms of these associations.

No phenotypic or genotypic evidence for a link between sleep duration and brain atrophy

Short sleep is held to cause poorer brain health, but is short sleep associated with higher rates of brain structural decline? Analysing 8,153 longitudinal MRIs from 3,893 healthy adults, we found no evidence for an association between sleep duration and brain atrophy. In contrast, cross-sectional analyses (51,295 observations) showed inverse U-shaped relationships, where a duration of 6.5 (95% confidence interval, (5.7, 7.3)) hours was associated with the thickest cortex and largest volumes relative to intracranial volume. This fits converging evidence from research on mortality, health and cognition that points to roughly seven hours being associated with good health. Genome-wide association analyses suggested that genes associated with longer sleep for below-average sleepers were linked to shorter sleep for above-average sleepers. Mendelian randomization did not yield evidence for causal impacts of sleep on brain structure. The combined results challenge the notion that habitual short sleep causes brain atrophy, suggesting that normal brains promote adequate sleep duration-which is shorter than current recommendations.

Cohort profile: The SmartSleep Study, Denmark, combining evidence from survey, clinical and tracking data

PURPOSE

The SmartSleep Study is established to comprehensively assess the impact of night-time smartphone use on sleep patterns and health. An innovative combination of large-scale repeated survey information, high-resolution sensor-driven smartphone data, in-depth clinical examination and registry linkage allows for detailed investigations into multisystem physiological dysregulation and long-term health consequences associated with night-time smartphone use and sleep impairment.

PARTICIPANTS

The SmartSleep Study consists of three interconnected data samples, which combined include 30 673 individuals with information on smartphone use, sleep and health. Subsamples of the study population also include high-resolution tracking data (n=5927) collected via a customised app and deep clinical phenotypical data (n=245). A total of 7208 participants are followed in nationwide health registries with full data coverage and long-term follow-up.

FINDINGS TO DATE

We highlight previous findings on the relation between smartphone use and sleep in the SmartSleep Study, and we evaluate the interventional potential of the citizen science approach used in one of the data samples. We also present new results from an analysis in which we use 803 000 data points from the high-resolution tracking data to identify clusters of temporal trajectories of night-time smartphone use that characterise distinct use patterns. Based on these objective tracking data, we characterise four clusters of night-time smartphone use.

FUTURE PLANS

The unprecedented size and coverage of the SmartSleep Study allow for a comprehensive documentation of smartphone activity during the entire sleep span. The study has been expanded by linkage to nationwide registers, which allow for further investigations into the long-term health and social consequences of night-time smartphone use. We also plan new rounds of data collection in the coming years.

Risk factors for insomnia and burnout: A longitudinal population-based cohort study

Insomnia and burnout are highly prevalent in the general population, calling for understanding of its causes. Taking a broad approach, the aim of this study was to determine various mental and somatic risk factors for development of insomnia and burnout and stratifying for sex and age group. Questionnaire data were used from a Swedish population-based sample aged 18-79 years, from which cohorts without insomnia (n = 1702) and without burnout (n = 1972) at baseline were followed-up after 3 years. Self-reports of eight mental and somatic conditions at baseline were used as independent variables in logistic regression analyses to predict development of insomnia and burnout at 3-year follow-up. All eight studied conditions were significant risk factors for development of both insomnia (odds ratio, OR = 1.62-2.73) and burnout (OR = 2.20-3.21). Burnout and poor self-rated health had the highest ORs for insomnia, and poor self-rated health, anxiety and somatic symptoms had the highest ORs for burnout. The ORs were generally similar between men and women, whereas age groups tended to differ in some of the risk factors. The study highlights the importance of a broad assessment of both mental and somatic conditions in the prevention of insomnia and burnout.

Green sleep: Immediate residential greenspace and access to larger green areas are associated with better sleep quality, in a longitudinal population-based cohort

OBJECTIVE

Sleep is pivotal to health, wellbeing and functioning in daily life, but sleep difficulties are common and may be affected by modifiable qualities in the residential surrounding environment, in terms of greenspace. However, population-based studies on individual-level greenspace and sleep are limited. The objective of the current study was thus to investigate prospective associations between fine-grained individual-level residential greenspace and sleep, and moderating effects of life style (physical activity, work status) and sex, in a nationwide population-based Swedish cohort.

METHODS

Participants of the Swedish Longitudinal Occupational Survey of Health (SLOSH)-a population-based sample of adults in Sweden-were studied during 2014-2018 (19,375 individuals; 43,062 observations). Residential greenspace land cover, and coherent green area size, were assessed via high resolution geographic information systems, at 50, 100, 300, 500 and 1000 m buffers around residences. Prospective greenspace and sleep associations were assessed via multilevel general linear models, adjusting for demographic, socioeconomic (individual and neighborhood), life style and urban factors.

RESULTS

Higher greenspace availability in the immediate residential surroundings (50 m and 100 m buffer zones) was associated with less sleep difficulties, even after adjustment for confounders. Greenspace effects were generally greater among non-working individuals. Among the physically active, and among non-working, greenspace and green area size further away from home (300, 500 and 1000 m, i.e. dependent on mobility) were also associated with less sleep difficulties.

CONCLUSIONS

Residential greenspace in the immediate residential surroundings is associated with significantly less sleep difficulties. Greenspace further away from home was associated with better sleep especially among the physically active, and non-working individuals. The results highlight the importance of greenspace in the immediate residential-surrounding environment for sleep, and the need to integrate health and environmental policies, urban planning and greening.

A Three-Way Interaction of Sex, PER2 rs56013859 Polymorphism, and Family Maltreatment in Depressive Symptoms in Adolescents

The prevalence of depressive symptoms in adolescents is 12-18% and is twice as frequent in females. Sleep problems and thoughts of death are depressive symptoms or co-occurrent phenomena. Family maltreatment is a risk factor for later depressive symptoms and the period circadian regulator (PER) has been studied in relation to neurotransmitters, adaptation to stress, and winter depression. The purpose of this work was to study the relation of the three-way interactions of sex, PER2 rs56013859, and family maltreatment in relation to core depressive symptoms, sleep complaints, and thoughts of death and suicide in self-reports from a cohort of Swedish adolescents in 2012, 2015, and 2018. Cross-sectional and longitudinal analyses with linear and logistic regressions were used to study the relationships to the three outcomes. The three-way interaction was related to core depressive symptoms at both baseline and six years later. In contrast, the model did not show any relation to the other dependent variables. At 13-15 years, a sex-related differential expression was observed: females with the minor allele C:C/C:T exposed to family maltreatment showed higher levels of core depressive symptoms. Six years later, the trend was inverted among carriers of minor alleles.

Is Short Sleep Bad for the Brain? Brain Structure and Cognitive Function in Short Sleepers

Many sleep less than recommended without experiencing daytime sleepiness. According to prevailing views, short sleep increases risk of lower brain health and cognitive function. Chronic mild sleep deprivation could cause undetected sleep debt, negatively affecting cognitive function and brain health. However, it is possible that some have less sleep need and are more resistant to negative effects of sleep loss. We investigated this using a cross-sectional and longitudinal sample of 47,029 participants of both sexes (20-89 years) from the Lifebrain consortium, Human Connectome project (HCP) and UK Biobank (UKB), with measures of self-reported sleep, including 51,295 MRIs of the brain and cognitive tests. A total of 740 participants who reported to sleep <6 h did not experience daytime sleepiness or sleep problems/disturbances interfering with falling or staying asleep. These short sleepers showed significantly larger regional brain volumes than both short sleepers with daytime sleepiness and sleep problems (n = 1742) and participants sleeping the recommended 7-8 h (n = 3886). However, both groups of short sleepers showed slightly lower general cognitive function (GCA), 0.16 and 0.19 SDs, respectively. Analyses using accelerometer-estimated sleep duration confirmed the findings, and the associations remained after controlling for body mass index, depression symptoms, income, and education. The results suggest that some people can cope with less sleep without obvious negative associations with brain morphometry and that sleepiness and sleep problems may be more related to brain structural differences than duration. However, the slightly lower performance on tests of general cognitive abilities warrants closer examination in natural settings.SIGNIFICANCE STATEMENT Short habitual sleep is prevalent, with unknown consequences for brain health and cognitive performance. Here, we show that daytime sleepiness and sleep problems are more strongly related to regional brain volumes than sleep duration. However, participants sleeping ≤6 h had slightly lower scores on tests of general cognitive function (GCA). This indicates that sleep need is individual and that sleep duration per se is very weakly if at all related brain health, while daytime sleepiness and sleep problems may show somewhat stronger associations. The association between habitual short sleep and lower scores on tests of general cognitive abilities must be further scrutinized in natural settings.

Stress and Sleep in Relation to Severity of Building Related Symptoms

OBJECTIVE

This study investigates different aspects of stress and sleep in medically examined individuals with varying severity of building-related symptoms (BRS).

METHODS

Three questionnaires were used to assess acute and long-term stress and sleep (Perceived Stress Scale; Shirom Melamed Burnout Questionnaire, and Karolinska Sleep Questionnaire).

RESULTS

Individuals with BRS, regardless of severity, did not differ in level of perceived stress (indicator of short-term stress). The indicators of long-term stress differed between the groups where an increased severity was associated with higher levels of burnout and sleep problems.

CONCLUSIONS

The study suggests an association between symptom severity and measures of long-term stress and sleep quality. This has implications for the treatment of persons affected by BRS, because not only the environment needs to be treated, but also the concurrent signs of distress, such as burnout or sleep problems.

Somatic symptoms in sleep disturbance

Despite sleep disturbance and somatic symptoms being common health complaints, the relationship between these disturbances and single somatic symptoms is not well documented. The objectives of this study were to (i) identify somatic symptoms that are particularly associated with sleep disturbance, here referred to as somatic symptoms related to sleep disturbance (SS-SD), (ii) determine increased risk of sleep disturbance for each SS-SD and for a certain number of SS-SD, with and without controlling for anxiety and depression, and (iii) determine sensitivity and specificity for identifying sleep disturbance based on number of SS-SD in a general Swedish sample. Population-based, cross-sectional data based on validated questionnaire instruments were used from participants who constituted a sleep disturbance (n = 864) or a reference (n = 2340) group. Among 15 common somatic symptoms, stomach pain, back pain nausea/gas/indigestion, dizziness, and constipation/loose bowels/diarrhea were identified as SS-SD, with odds ratios of increased risk of sleep disturbance that ranged from 1.93 to 2.44 (1.36-1.79 and 1.54-1.91 when controlled for anxiety and depression, respectively). The risk of sleep disturbance increased by 1.44 times for each SS-SD (1.25 and 1.30 when controlled for anxiety and depression, respectively). A cutoff of two/three or more SS-SD had a sensitivity of 72.5/54.2% and a specificity of 50.0/69.7% for identifying sleep disturbances. When patients present with these somatic symptoms with or without a pathophysiological explanation, primary care clinicians may consider screening for sleep disturbance.

A Quantitative Study on Employees' Experiences of a Support Model for Systematic Work Environment Management in Swedish Municipalities

Today's working life is constantly changing, and work environmental risk factors can alter swiftly. Besides the traditional physical work environment risk factors, somewhat more abstract organizational and social work environment factors also play an ever-increasing role, both in preventing and causing work-related illness. This requires a preventive work environment management that can respond to rapid changes, and where the assessment and remedies rely more on employee participation than on predetermined threshold limits. This study aimed to investigate if the use of a support model (the Stamina model) for workplace improvements could render the same positive effects in quantitative measures that have previously been shown in qualitative studies. Employees from six municipalities used the model for 12 months. They answered a questionnaire at baseline and after six and 12 months, to detect any changes in how they characterized their current work situation and perceived their influence, productivity, short-term recovery, and organizational justice. The results showed that employees felt more influential in work situations related to communication/collaboration and roles/tasks at the follow-up compared to the baseline. These results are consistent with previous qualitative studies. We found no significant changes in the other endpoints. The results strengthen previous conclusions, namely that the Stamina model can be used as part of inclusive, modern, and systematic work environment management.

Study protocol for a multicenter randomized controlled trial of personalized exercise therapy and self-management support for people with multimorbidity: The MOBILIZE study

Background

Despite the great individual and societal burden associated with multimorbidity, little is known about how to effectively manage it.

Objective

The aim of this multicenter randomized controlled trial (RCT) is to investigate the 12-month effects of a personalized exercise therapy and self-management support program in addition to usual care in people with multimorbidity.

Design

This is a protocol for a pragmatic, parallel-group (1:1 ratio), superiority RCT conducted at five intervention sites (two hospitals, a private practice physiotherapy clinic and two municipal rehabilitation centers) in Region Zealand, Denmark. A total of 228 persons with multimorbidity aged 18 years or older, will be randomly allocated to one of two groups. Both groups will receive usual care, defined as routine care for multimorbidity at the discretion of the treating doctor, while the intervention group will also participate in a 12-week exercise therapy and self-management support program tailored to people with multimorbidity at one of the intervention sites. The primary outcome will be the between-group difference in change in EQ-5D-5L from baseline to the follow-up at 12 months. Secondary outcomes include objectively-measured physical function and physical activity, inflammatory markers, disease and treatment burden, anxiety, depression, stress, sleep, pain and other self-reported parameters. In parallel with the RCT, an observational cohort will follow persons aged ≥18 years with multimorbidity not adhering to all eligibility criteria, as well as people fulfilling all eligibility criteria, but unwilling to participate in the RCT. This study was approved by the Regional Committee on Health Research Ethics for Region Zealand (SJ-857) and results will be communicated in scientific papers, at relevant conferences and to a broader audience.

Discussion

Exercise therapy and self-management support is safe and effective in people with single conditions. However, it is still unclear whether this holds true for individuals with multimorbidity. This pragmatic, multicenter RCT will provide high-quality evidence on the benefits and harms of exercise therapy and self-management support and, if the results support it, lead to the development of a plan for implementation in clinical practice.

Stress, mental ill-health and functional somatic syndromes in incident and chronic sleep disturbance in a general adult population

Objective

Sleep disturbance may constitute health problems for the afflicted individual, but documentation of its chronicity is sparse. The objective was to investigate the extent to which incident and chronic sleep disturbance are associated with stress, mental ill-health and functional somatic syndromes.

Design

This was a prospective, longitudinal study with 3-year interval between two assessments (T1 and T2), with a population-based sample forming groups with incident sleep disturbance (disturbance only at T2; n = 303), chronic sleep disturbance (disturbance at T1 and T2; n = 343) and without sleep disturbance (neither at T1 nor T2; n = 1421). Questionnaire data were used at T2 of physician-based diagnosis of anxiety disorder, depression, exhaustion syndrome, and functional somatic syndrome as well as of degree of stress, burnout, anxiety and depression.

Results

Significant associations were found between chronic sleep disturbance and all four diagnoses (odds ratios = 1.74-2.19), whereas incident sleep disturbance was associated only with exhaustion syndrome and depression (odds ratios = 2.18-2.37). Degree of stress, burnout, anxiety and depression increased significantly from the referents to incident and chronic sleep disturbance, in that order (eta² = 0.083-0.166), except for the two latter groups not differing in depression.

Conclusion

The findings imply that healthcare professionals should be observant regarding various conditions of, apart from stress, mental ill-health and functional somatic syndromes in patients who present themselves with sleep disturbance, and in particular chronic disturbance.

Worsened Anxiety and Loneliness Influenced Gaming and Gambling during the COVID-19 Pandemic

Aim: To study the prevalence and patterns of problematic gaming and gambling during the COVID-19 pandemic and the association with psychiatric traits and major types of anxiety categories. Method: 1067 young adults participated in both wave 3 (2018) and wave 4 (2021) of the SALVe Cohort. Associations with psychiatric symptoms and anxiety were examined using logistic regression and Chi-square tests. Results: Problematic gaming decreased by 1.3 percentage points to 23.2% since the start of the pandemic, while problematic gambling increased by 0.9 percentage points to 6.5% in w4. Average time spent playing video games/day decreased from 2.2 h (w3) to 1.7 h (w4), while increases in gaming activity were associated with worsened feelings of loneliness (p = 0.002), depression (p < 0.001), and anxiety (p < 0.01) during the pandemic. Predictors for problematic gaming at w4 were previous problematic gaming and social anxiety (p = < 0.001 and 0.01, respectively). Moreover, previous problem gambling also predicted problem gambling at w4 p < 0.001. All anxiety categories were associated with both problematic gaming and gambling when adjusted for age and sex. However, after adjusting for depression and insomnia, social anxiety was associated with problematic gaming (p < 0.001), while panic was associated with problem gambling (p < 0.001). Conclusion: Overall, problematic gaming has decreased since the start of the pandemic, while problem gambling has increased. Worsened feelings of loneliness, depression, and anxiety during the pandemic are associated with increased gaming. Moreover, the association between problematic gaming and gambling and anxiety is independent of depression and sleep problems.

A Matter of Health? A 24-Week Daily and Weekly Diary Study on Workplace Bullying Perpetrators' Psychological and Physical Health

Workplace bullying (WB) studies focusing on perpetrators are increasing. Many processes, events, circumstances and individual states are being studied to understand and inhibit what causes some employees to become perpetrators. Using a 24-week diary design and drawing on the Conservation of Resources Theory, we investigated how sleep, physical activity (PA), and being bullied predicted perpetration on a within-level. On a between-level, we controlled for a supervisory position, psychological distress and mental illnesses over 38 employees from Spain and Turkey. Their average age was 38.84 years (SD = 11.75). They were from diverse sectors (15.8% in manufacturing, 15.8% in education, 13.2% in wholesale and retail trade, 13.2% in information and communication, 7.9% in health, 7.9% in other services and 26.3% from other sectors) with diverse professions such as finance manager, psychologist, graphic designer, academic, human resources professional, forensic doctor, IT and Administration head, municipality admin executive, waiter, and sales executives. Data collection was conducted over 24 consecutive work weeks, where only 31 participants were involved in perpetration (final observations = 720). We analyzed the data using multilevel structural equation modeling decomposed into within-and-between-person variance parts. The results indicated that on a within-level, PA as steps taken during the work week and being bullied positively predicted perpetration the same week, while sleep quality did not. By connecting sleep, physical exercise and WB literature, we draw attention to the health condition of perpetrators. Organizations should actively inhibit workplace bullying and be mindful of employees' physical activities at work or commuting to work. Managers should also be attentive to physical fatigue that employees may feel due to their responsibilities in their private lives and allow employees to rest and recuperate to inhibit negative behaviors at work.

Health Consequences of the COVID-19 Pandemic among Health-Care Workers: A Comparison between Groups Involved and Not Involved in COVID-19 Care

Health consequences have been reported among health-care workers (HCWs) exposed to COVID-19. Sweden chose to manage the pandemic with a lower and more equal long-lasting work strain and shorter periods of recovery than in other countries. Few studies have examined the health consequences among HCWs working in such conditions. This study compared the health consequences after the first wave of the COVID-19 pandemic between HCWs involved in the care of COVID-19 patients and other HCWs and between occupational groups working in COVID-19 care. Multinomial logistic regression and univariate general linear models were used to identify differences. The levels of depression, emotional and physical fatigue, sleep quality, and general health were measured 6 months after the onset of the pandemic in 3495 HCW employed in Sweden. HCWs directly involved in COVID-19 care reported significantly poorer sleep quality and higher scores on emotional and physical exhaustion than those not involved in such care. Health consequences did not differ significantly between different occupational groups involved in COVID-19 care except for specialist nurses/midwives. HCWs more frequently involved in COVID-19 care reported higher levels of emotional and physical fatigue and poorer sleep but less severe than those reported in more severely affected countries.

Construct validation and normative data for different versions of the Shirom-Melamed burnout questionnaire/measure in a Swedish population sample

The overall aim of the present study was to examine the construct validity of different versions of the Shirom-Melamed Burnout Questionnaire/Measure (SMBQ/M) suggested in previous work, as well as to provide normative data for a large population-based sample in Sweden with a broad range in age. Cross-sectional data from the Västerbotten Environmental Health Study in Sweden were used. The 3406 participants (56% women) in this study, aged 18-79 years, constituted a random sample stratified for age and sex. Participants responded to a questionnaire including the 4-factor 22-item version of the SMBM as well as background questions and a number of validated questionnaire instruments assessing for example, sleep disturbance, depression, anxiety, perceived stress, and somatic symptoms. The dimensionality of different versions of the SMBM were examined with confirmatory factor analysis. A modified 4-factor 19-item model of the SMBM provided good model-fit, and two 2-factor models (11-item and 6-item) provided excellent model fit. The relationships to relevant psychological constructs provided support for convergent validity for the suggested versions of the SMBM. Finally, normative data were obtained for a broad age group for the different versions. In conclusion, we suggest that for assessing the core of the burnout construct in terms of emotional and physical exhaustion and cognitive weariness, the SMBM-11 or SMBM-6 for repeated measures, are to be used. For a broader assessment of burnout incorporating both symptoms and information about the process of exhaustion via the subscales of listlessness and tension, we recommend the use of the modified 4-factor SMBM-19.

Fatigue 7 years post-stroke: Predictors and correlated features

Background

Post‐stroke fatigue (PSF) is common with great impact on quality of life. We explored predictive and cross‐sectionally correlated features in the long term after ischemic stroke.

Methods

This study comprises 430 participants of the prospective Sahlgrenska Academy Study on Ischemic Stroke (SAHLSIS), aged 18–69 years at index stroke. Information on acute stroke severity and cardiovascular risk factors was collected at index stroke. After 7 years, PSF was assessed by the Daily Fatigue Impact Scale (D‐FIS). Cognitive, neurological, and functional outcomes, and symptoms of depression and anxiety, pain, insomnia, and physical activity were also assessed. Associations between baseline variables and PSF were analyzed by ordinal regression. Correlations between PSF and cross‐sectionally assessed variables, and between PSF and baseline variables, were analyzed with Spearman's or point‐biserial correlation for the whole sample and in sex‐stratified analyses.

Results

At 7 years post‐stroke, 80% of the participants reported some impact of fatigue. Female sex and stroke severity were independently associated with PSF, whereas no associations were detected with baseline cardiovascular risk factors. In cross‐sectional analyses at 7 years, we found correlations between PSF and poor functional, neurological, and cognitive outcomes, as well as depressive symptoms, anxiety, insomnia, pain, and low physical activity (p < .001 throughout). The correlation with insomnia was stronger in women than in men (two‐way ANOVA interaction test, p = .03).

Conclusions

Our findings confirm that PSF is common in the long term after ischemic stroke and show a complex interplay with sex and several other outcomes. Future studies should address causal relationships and interventions towards fatigue and coexisting features.

Alcohol Use among Swedish Patients with Stress-Induced Exhaustion Disorder, and Its Relation to Anxiety, Depression, and Health-Related Quality of Life

Harmful drinking may be a cause and an effect of psychological distress, and compromises the effects of treatment for psychiatric conditions. There is a paucity of studies investigating patterns of alcohol consumption among patients with stress-induced exhaustion disorder (SED). The aims of this investigation were (1) to assess the prevalence of self-rated hazardous drinking in a sample of 808 Swedish patients with SED (mean age 43 ± 9 years, 84% women), and (2) to investigate differences in sociodemographic variables, psychological symptoms, health-related quality of life, and sleep variables between patients with different drinking patterns The design was cross-sectional and data were collected with questionnaires at pre-treatment. Twelve percent of female and 13% of male patients reported Alcohol Use Disorder Identification Test (AUDIT) scores indicating hazardous drinking. Female patients with hazardous drinking reported higher levels of anxiety and depression and lower mental wellbeing, than other women. Female patients reporting no drinking reported poorer physical function and more pain, than other women. No differences were seen between male patients with different drinking patterns. Although patients with SED report a lower frequency of harmful drinking than other psychiatric samples, alcohol consumption needs to be addressed in the assessment and treatment of this condition.

Flexible Work: Opportunity and Challenge (FLOC) for individual, social and economic sustainability. Protocol for a prospective cohort study of non-standard employment and flexible work arrangements in Sweden

INTRODUCTION

Flexibility in working life, including non-standard employment (NSE) and flexible work arrangements (FWAs), offers the organisation a better ability to adapt to changing conditions while also posing considerable challenges for organisations as well as workers. The aim of the Flexible Work: Opportunity and Challenge (FLOC) study is to investigate associations between NSE and FWA on the one hand, and individual, social and economic sustainability on the other.

METHODS AND ANALYSIS

This prospective open cohort study targets approximately 8000 workers 18-65 years old in 8-10 public and private organisations in Sweden. We will use a comprehensive battery of measurement methods addressing financial performance, physical and psychosocial exposures, and physical and mental health, both at the organisational and the individual level. Methods include valid survey questionnaires and register data, and, in subpopulations, technical measurements, interviews and diaries. Main exposures are type of employment and type of work arrangement. Main outcomes are indicators of social and economic sustainability and, at the individual level, health and well-being. Data, collected over 54 months at approximately 18-month intervals, will be analysed using multivariate methods considering main effects as well as potential effect modifiers. The analyses will take into account that respondents are nested in organisations, divisions and/or have specific managers.

ETHICS AND DISSEMINATION

FLOC is approved by the Swedish Ethical Review Authority (decision numbers 2019-06220, 2020-06094 and 2021-02725). Data will be published in peer-reviewed journals and presented at international conferences, and researchers will assist the organisations in improving policies and routines for employment and organisation of work.

Unmet Needs in Rheumatoid Arthritis: A Subgroup of Patients With High Levels of Pain, Fatigue, and Psychosocial Distress 3 Years After Diagnosis

Objective

The study objective was to identify subgroups of patients with rheumatoid arthritis (RA) based on their health status 3 years after diagnosis and to assess potential associations to clinical presentation at diagnosis.

Methods

This observational study included patients with RA with 3‐year follow‐up data from the Swedish Epidemiological Investigation of RA study, collected from 2011 to 2018. Hierarchical agglomerative cluster analysis, based on symptoms of pain, fatigue, sleep quality, mood disturbances, and overall health‐related quality of life (HRQoL), was used to identify subgroups 3 years after diagnosis. Modified Poisson regression was used to estimate risk ratios (RRs) and 95% confidence intervals (CIs) for the associations between the subgroups and patient characteristics at diagnosis.

Results

A total of 1055 individuals constituted the study population, of whom 1011 had complete data on the clustering variables and were therefore eligible for analysis (73% women, median age 58 years). The following three clusters were identified: cluster 1 (466 patients with good health status), cluster 2 (398 patients in an intermediate group), and cluster 3 (147 patients with high levels of pain and fatigue together with markedly impaired HRQoL). Cluster 3 was associated to higher baseline pain (RR: 3.71 [95% CI: 2.14‐6.41]), global health (RR: 6.60 [95% CI: 3.53‐12.33]), and the Stanford Health Assessment Questionnaire (RR: 4.40 [95% CI: 2.46‐7.87]), compared with cluster 1 (highest compared with lowest quartiles). An inverse association was seen for baseline swollen joint count (RR: 0.51 [95% CI: 0.34‐0.85]).

Conclusion

A subgroup of patients with RA experience high levels of pain, fatigue, and psychosocial distress 3 years after diagnosis. This subgroup already displayed pronounced pain and functional disabilities at diagnosis.

Psychological models of development of idiopathic environmental intolerances: Evidence from longitudinal population-based data

The origin of idiopathic environmental intolerances (IEIs) is an open question. According to the psychological approaches, various top-down factors play a dominant role in the development of IEIs. The general psychopathology model assumes a propensity towards mental ill-health (negative affectivity) increases the probability of developing IEIs. The attribution model emphasizes the importance of mistaken attribution of experienced somatic symptoms; thus, more symptoms should lead to more IEIs. Finally, the nocebo model highlights the role of expectations in the development of IEIs. In this case, worries about the harmful effects of environmental factors are assumed to evoke IEIs. We estimated cross-lagged panel models with latent variables based on longitudinal data obtained at two time points (six years apart) from a large near-representative community sample to test the hypothesized associations. Indicators of chemical intolerance, electromagnetic hypersensitivity, and sound sensitivity fit well under a common latent factor of IEIs. This factor, in turn, showed considerable temporal stability. However, whereas a positive association was found between IEIs and increased somatic symptoms and modern health worries six years later, the changes therein could not be predicted as hypothesized by the three psychological models. We discuss the implications of these results, as well as methodological aspects in the measurement and prediction of change in IEIs.

The Role of Comorbid Symptoms in Perceived Stress and Sleep Problems in Adolescent ADHD

We examined perceived stress and sleep problems in adolescent ADHD and whether this varies as a function of ADHD presentation and sex. Further, we mapped structural associations between ADHD symptoms, comorbid symptoms, perceived stress, and sleep problems. Participants were 306 adolescents aged 13-19 years (66.8% females, 193 had an ADHD diagnosis, 113 were controls). Parents rated ADHD symptoms, all other constructs were self-rated. Adolescents with ADHD had elevated levels of perceived stress and sleep problems. Girls with ADHD reported the highest levels of perceived stress. Emotional symptoms mediated the effect of inattention whereas conduct problems mediated the effect of hyperactivity/impulsivity on stress and sleep. Perceived stress and sleep problems should be considered when mapping ADHD-related problems. Comorbid symptoms are potential intervention targets that may increase treatment response.

Obstructive sleep apnea is common in patients with high-impact chronic pain - an exploratory study from an interdisciplinary pain center

OBJECTIVES

Sleep disturbances are increasingly recognized as a major part of chronic pain pathology. Obstructive sleep apnea (OSA) is a common occurrence in patients with chronic pain attending specialized pain clinics, yet its prevalence remains unclear. Using screening tools such as the Berlin and STOP-BANG questionnaires may aid in early identification of OSA and improve clinical care. This study i) examined the frequency of OSA based on objective sleep monitoring in patients with high-impact chronic pain, ii) explored potential differences in self-reported pain and sleep characteristics between patients with and without OSA, and iii) tested the agreement between OSA classification based on objective assessment and two OSA screening questionnaires.

METHODS

A consecutive cohort of 90 patients (71 women and 19 men; mean age: 47.1 ± 11.0 years) referred for interdisciplinary pain treatment, underwent one night of sleep monitoring using portable respiratory polygraphy (RP), and suspected OSA was confirmed with polysomnography (PSG). Self-reported data on clinical pain (severity, pain drawings and health-related quality of life), sleep characteristics (sleep quality insomnia, sleepiness), and risk of OSA (Berlin and STOP-BANG questionnaires) were collected the day before RP assessment.

RESULTS

Forty-six (51.1%) patients were classified with OSA according to RP and verified with PSG. Twenty-eight patients (31.1%) had moderate or severe OSA (apnea-hypopnea index [AHI] >15). Patients with OSA reported lower sleep quality compared with patients without OSA. Scores on pain severity, disability, quality of life, insomnia and sleepiness were comparable between patients with and without OSA. Sensitivity and specificity were 78.6 and 45.2% respectively for the Berlin questionnaire, and 71.4 and 58.1% respectively for the STOP-BANG questionnaire. The agreement for both questionnaires with objective assessment was poor-to-fair. Both questionnaires had acceptable negative predictive values but low positive predictive values reducing the clinical utility to identify patients with low OSA-risk in this sample.

CONCLUSIONS

The current study demonstrates a high prevalence of OSA in patients with high-impact chronic pain referred to specialized pain treatment, however the clinical pain profiles were similar in patients with and without OSA. The Berlin and STOP-BANG questionnaires have poor specificity and low-to-fair agreement with RP/PSG questioning their clinical utility in identifying OSA in this sample.

Work changes and employee age, maladaptive coping expectations, and well-being: a Swedish cohort study

Purpose

Older workers are expected to suffer more from work changes than younger ones, but empirical evidence is lacking. Negative responses to work changes may result rather from maladaptive coping expectations. This study examined possible age differences in job and life satisfaction, and sleep disturbances, after work changes (voluntary and involuntary job changes, reorganizations) and the moderating role of maladaptive coping expectations.

Methods

Four biennial waves from the Swedish Longitudinal Occupational Survey of Health (SLOSH) including respondents who participated in all four waves (n = 3084). We used multilevel path analyses to estimate direct and moderated relationships between work changes and outcomes.

Results

Involuntary job changes were associated with lower job and life satisfaction and more sleep disturbances. Reorganizations were only associated with lower job satisfaction. Older employees were more satisfied with their jobs and lives than younger employees and experienced more sleep disturbances. After involuntary job changes, older employees had similar (lower) levels of well-being as younger ones, but they reported more sleep disturbances when having experienced reorganizations. Maladaptive coping expectations were related to lower job and life satisfaction and more sleep disturbances. Employees with maladaptive coping expectations reported more sleep disturbances after involuntary job changes and reorganizations.

Conclusion

Our results suggest that there are few age differences in well-being after work changes. Employee well-being seems to mostly depend on maladaptive coping expectations. Organizations aiming to prepare employees for job changes and reorganizations could focus their efforts on employees with maladaptive expectations rather than on older ones.

Sleep problems in rheumatoid arthritis over 12 years from diagnosis: results from the Swedish EIRA study

Objective

Most studies of rheumatoid arthritis (RA) and sleep have focused on established RA. We here investigate sleep quality and sleep duration in patients with newly diagnosed RA and during 1–12 years after diagnosis.

Methods

Data were collected on sleep 1–12 years after diagnosis from patients diagnosed 1998–2018 in the Swedish study Epidemiological Investigation of RA. Six sleep domains (sleep problems, non-restorative sleep, insomnia, insufficient sleep, sleep quality perceived as poor and sleep considered a health problem); a global sleep score and time spent in bed were estimated. Using logistic regression, ORs were calculated for each sleep outcome by disease duration. We explored whether pain (low (Visual Analogue Scale=0–20 mm, reference), intermediate=21–70, high=71–100) or functional impairment (Health Assessment Questionnaire>1.0) was associated with problems.

Results

We had sleep data on 4131 observations (n=3265 individuals). Problems with ≥1 sleep domain (global sleep score) was reported in 1578 observations (38%) and increased with disease duration (OR 1.04, 95% CI 1.02 to 1.07). Median time in bed was 8 hours (Q1-Q3: 7.5–9.0). High-grade pain increased the likelihood of sleep problems ~3–9 fold, and increased functional impairment ~4–8 fold.

Conclusion

In this cohort of newly diagnosed patients with RA with access to the current treatment from diagnosis, we did not find any major problems with sleep, and existing sleep problems related mainly to pain and reduced function. Treatment of sleep problems in RA should be guided towards treating the underlying problem causing the sleep disturbance.

Measuring the Impact of Operational Stress: The Relevance of Assessing Stress-related Health Across the Deployment Cycle

INTRODUCTION

Mental health issues from intense or prolonged stress are a common concern in regard to military deployment. Deployments can objectively vary in stress exposure, but it is the individuals' perception of that stress that affects sustainability, mental health, and combat fitness, which calls for the need of a protocol to evaluate and maintain a current estimation of stress impact. So, how can we assess the impact of stressors during different phases of deployment?

MATERIALS AND METHODS

We used three psychological self-rating forms, the PSS14-Perceived Stress Scale, SMBM-Shirom Melamed Burnout Measure, and KSQ-Karolinska Sleep Questionnaire, to measure the impact of stress before (T1), during (T2), and at homecoming (T3). We also wanted to see if T1 or T2 results could predict T3 results to be able to better prepare the homecoming program.The forms were handed out to Swedish soldiers deployed in Mali in 2017. The forms were collected as a way to assess the status of the mental health load at three timepoints based on the personnel function as a way to assess the current "psychological fitness level".

RESULTS

The results show that stress measured using PSS14 was high at homecoming. The same result was observed for SMBM. No measures from T1 or T2 could however predict the T3 results.

CONCLUSIONS

Taken together, we found that screening of all contingent staff is relatively easy and provides personnel with relevant data on mental health and stress at the current time. We also found that test results correlated between T1 and T2 but not with T3. This indicates that there might be different stressors that affect staff at different timepoints.

The potential impacts of circadian rhythm disturbances on male fertility

A circadian rhythm is an internalized timing system that synchronizes the cellular, behavioral, and physiological processes of organisms to the Earth's rotation. Because all physiological activities occur at a specific time, circadian rhythm disturbances can lead to various pathological disorders and diseases. Growing evidence has shown that the circadian clock is tightly connected to male fertility, and circadian perturbations contribute to infertility. The night shiftwork, insufficient sleep, and poor sleep quality are common causes of circadian disturbances, and many studies have reported that they impair sperm quality and increase the risk of male infertility. However, research on the impacts of light, body temperature, and circadian/circannual rhythms is relatively lacking, although some correlations have been demonstrated. Moreover, as the index of sperm quality was diverse and study designs were non-uniform, the conclusions were temporarily inconsistent and underlying mechanisms remain unclear. A better understanding of whether and how circadian disturbances regulate male fertility will be meaningful, as more scientific work schedules and rational lifestyles might help improve infertility.

Evaluation of a structured skills training group for adolescents with attention-deficit/hyperactivity disorder: a randomised controlled trial

Attention-deficit/hyperactivity disorder (ADHD) in adolescence is associated with behavioural, emotional and interpersonal problems, and non-pharmacological treatments targeting these difficulties have been requested. The objective of this study was to evaluate the effectiveness and acceptance of an age-adapted structured skills training group (SSTG) for adolescents with ADHD. Adolescents (n = 184, ages 15-18 years) with a diagnosis of ADHD were randomly assigned to either the SSTG, which is based on dialectical behavioural therapy, or an active control group based on psychoeducation. Symptoms of ADHD, behavioural and emotional problems, functional impairment, and health-related outcomes were assessed with self-ratings and parental ratings two weeks before, two weeks after, and six months after treatment. All participants who completed the pre-treatment measurements (n = 164) were included in the main analyses, which were conducted using a linear mixed model. Our results demonstrated no significant group differences in favour of the SSTG for any of the study outcomes. A majority of the participants in both groups reported that they had increased their knowledge about ADHD, improved their ability to manage problems related to the diagnosis, and would recommend the treatment to others. We conclude that the SSTG seems to be acceptable for adolescents with ADHD in a clinical context. However, the treatment was not proved to be more effective or more acceptable than the psychoeducational control intervention.Trial registration: http://www.isrctn.com/ISRCTN17366720,11/05/2016 , retrospectively registered.

A longitudinal study of morning, evening, and night light intensities and nocturnal sleep quality in a working population

We aimed to investigate whether higher light intensity in the morning is associated with better nocturnal sleep quality and whether higher light intensities in the evening or night have the opposite effect. Light intensity was recorded for 7 consecutive days across the year among 317 indoor and outdoor daytime workers in Denmark (55-56° N) equipped with a personal light recorder. Participants reported sleep quality after each nocturnal sleep. Sleep quality was measured using three parameters; disturbed sleep index, awakening index, and sleep onset latency. Associations between increasing light intensities and sleep quality were analyzed using mixed effects models with participant identity as a random effect. Overall, neither white nor blue light intensities during morning, evening, or night were associated with sleep quality, awakening, or sleep onset latency of the subsequent nocturnal sleep. However, secondary analyses suggested that artificial light during the morning and day contrary to solar light may increase vulnerability to evening light exposure. Altogether, we were not able to confirm that higher morning light intensity significantly improves self-reported sleep quality or that higher evening or night light intensities impair self-reported sleep quality at exposure levels encountered during daily life in a working population in Denmark. This suggests that light intensities alone are not important for sleep quality to a degree that it is distinguishable from other important parameters in daily life settings.

Predictors of interindividual differences in vulnerability to neurobehavioral consequences of chronic partial sleep restriction

Interindividual differences in the neurobehavioral response to sleep loss are largely unexplained and phenotypic in nature. Numerous factors have been examined as predictors of differential response to sleep loss, but none have yielded a comprehensive view of the phenomenon. The present study examines the impact of baseline factors, habitual sleep-wake patterns, and homeostatic response to sleep loss on accrued deficits in psychomotor vigilance during chronic partial sleep restriction (SR), in a total of 306 healthy adults that participated in one of three independent laboratory studies. Findings indicate no significant impact of personality, academic intelligence, subjective reports of chronotype, sleepiness and fatigue, performance on working memory, and demographic factors such as sex, ethnicity, and body mass index, on neurobehavioral vulnerability to the negative effects of sleep loss. Only superior baseline performance on the psychomotor vigilance test and ability to sustain wakefulness on the maintenance of wakefulness test were associated with relative resilience to decrements in vigilant attention during SR. Interindividual differences in vulnerability to the effects of sleep loss were not accounted for by prior sleep history, habitual sleep patterns outside of the laboratory, baseline sleep architecture, or homeostatic sleep response during chronic partial SR. A recent theoretical model proposed that sleep-wake modulation may be influenced by competing internal and external demands which may promote wakefulness despite homeostatic and circadian signals for sleep under the right circumstances. Further research is warranted to examine the possibility of interindividual differences in the ability to prioritize external demands for wakefulness in the face of mounting pressure to sleep.

How consistently does sleep quality improve at retirement? Prospective analyses with group-based trajectory models

Growing evidence indicates that retiring from paid work is associated, at least in the short-term, with dramatic reductions in sleep difficulties and more restorative sleep. However, much is still not known, in particular how universal these improvements are, how long they last, and whether they relate to the work environment. A methodological challenge concerns how to model time when studying abrupt changes such as retirement. Using data from Swedish Longitudinal Occupational Survey of Health (n = 2,148), we studied difficulties falling asleep, difficulties maintaining sleep, premature awakening, restless sleep, a composite scale of these items, and non-restorative sleep. We compared polynomial and B-spline functions to model time in group-based trajectory modelling. We estimated variations in the individual development of sleep difficulties around retirement, relating these to the pre-retirement work environment. Reductions in sleep difficulties at retirement were sudden for all outcomes and were sustained for up to 11 years for non-restorative sleep, premature awakening, and restless sleep. Average patterns masked distinct patterns of change: groups of retirees experiencing greatest pre-retirement sleep difficulties benefitted most from retiring. Higher job demands, lower work time control, lower job control, and working full-time were work factors that accounted membership in these groups. Compared to polynomials, B-spline models more appropriately estimated time around retirement, providing trajectories that were closer to the observed shapes. The study highlights the need to exercise care in modelling time over a sudden transition because using polynomials can generate artefactual uplifts or omit abrupt changes entirely, findings that would have fallacious implications.

Commuting distance and behavior-related health: A longitudinal study

Health benefits of active commuting and short commuting time are well-documented; however, limited evidence exists on the effects of commuting distance. We examined longitudinal associations between commuting distance and behavior-related health. Participants were from four survey waves of the Swedish Longitudinal Occupational Survey of Health (2012, 2014, 2016, and 2018). Analytical sample included 11,023 individuals and 21,769 observations. Random effects method used binomial logistic regression with generalized estimating equations. The outcomes were self-reported physical inactivity, overweight, smoking, problem drinking, and disturbed sleep. Models were adjusted for age, sex, occupational position, civil status, chronic disease, work strain, number of children under 12, and home/workplace neighborhood socioeconomic status. Using continuous measure, long commuting distance was associated with a higher odds of physical inactivity (OR 1.06; 95% CI, 1.04-1.09 per doubling of distance), overweight (OR 1.02; 95% CI, 1.00-1.04), and disturbed sleep (OR 1.03; 95% CI, 1.00-1.05) in fully adjusted models. Using categorized measure, individuals who commuted longer distance had a higher odds of physical inactivity compared to those with the shortest commute (3.1 km - <7.9 km vs. <3.1 km: OR 1.15; 95% CI, 1.04-1.28 and 7.9 km - <20 km vs. <3.1 km: OR 1.18; 95% CI, 1.06-1.32, fully adjusted model). Such dose-response associations were not observed for overweight or disturbed sleep. Our results suggest short commuting distance may be beneficial for behavior-related health.