The association between sleep quantity, insomnia and lung cancer risk - A systematic review and meta-analysis.

PURPOSE: The effect of various sleep traits on the risk of lung cancer differs among pre-existing studies. This study aims to systematically review and synthesise the association between sleep duration and insomnia with the incidence of lung cancer. METHODS: PubMed, Embase and The Cochrane Library were searched from inception to 23 April 2023 for observational studies examining the effect of sleep quantity or insomnia on lung cancer incidence. We pooled maximally-adjusted hazard ratios and odds ratios separately using random effects inverse variance weighted models. The risk of bias of observational studies was assessed using the Newcastle-Ottawa Scale. RESULTS: We included 11 observational studies with a pooled cohort of 5,049,141 patients. The mean age of the patients was 49.5 ± 17.7 years, and 51.4% were males. The risk of bias ranged from low-moderate. Individuals who slept for a shorter or longer duration than the reference range of sleep per night showed an increased risk of lung cancer by 11% (HR:1.11; 95%CI:1.00-1.23) and 16% (HR:1.16; 95%CI:1.06-1.27) respectively. Furthermore, individuals with insomnia symptoms had a 9% greater risk of lung cancer than those without symptoms (HR:1.09; 95%CI:1.05-1.13). CONCLUSION: This study suggests that insufficient sleep, excessive sleep and insomnia may be associated with an increased risk of lung cancer. Physicians should be mindful of this association and encourage healthy sleep practises among patients. Given the observed heterogeneity among some pre-existing studies, future research with longer periods of follow-up, greater control for covariates and objective testing of sleep parameters may add value to this topic.

Association of sleep with moral severity to accidental harm transgressions: A cross-sectional study.

Based on the assumptions that moral judgement activities require cognitive control, a capacity impaired by low sleep quality or a lack of sleep, several studies have explored the association between sleep and moral judgements. However, even if some studies support the association between sleep and both moral awareness and unethical behaviours, others failed to find a robust association between sleep and moral utilitarianism. In the present well-powered preregistered cross-sectional study, we explored the role of sleep in another class of moral judgement, namely third-party punishment (in which people have to assess the morality of an agent who transgressed a moral rule). Specifically, we targeted the association of sleep with judgements of accidental harm transgressions, which are assumed to be especially cognitively costly. Our main analysis showed no association of overall sleep quality during the past month with moral severity in these transgressions. This result was confirmed for other sleep indexes (sleep quantity in the past month, and sleep quantity and quality in the past night). Lastly, we exhaustively explored the associations of all sleep indexes with all classes of moral judgement (accidental, intentional, attempted transgressions and control scenarios). These additional results revealed associations between sleep and moral severity, but none survived correction for multiple testing. Equivalence tests confirmed that the effect sizes of all these associations were relatively low (|r < 0.25|). We ensured that the lack of robust association between natural sleep and third-party punishment could not be explained by a low quality of the data collected.

Longitudinal associations between self-reported sleep duration and cardiometabolic disease risk in corporate executives.

OBJECTIVE: This study aimed to determine the longitudinal associations between self-reported sleep duration and cardiometabolic disease (CMD) risk in corporate executives. METHODS: Self-reported sleep duration and lifestyle, occupational, psychological, and anthropometrical, blood pressure and blood marker variables were obtained from 1512 employees at annual health risk assessments in South Africa between 2016 and 2019. Gender-stratified linear mixed models, adjusting for age, lifestyle, occupational and psychological covariates were used to explore these longitudinal associations. RESULTS: Among women, shorter sleep duration was associated with higher body mass index (BMI) covarying for age only (ß with 95% confidence intervals: -0.19 [-0.36, -0.03]), age and occupational factors (-0.20 [-0.36, -0.03]) and age and psychological factors (-0.20 [-0.37, -0.03]). Among men, shorter sleep was associated with both BMI and waist circumference (WC) covarying for age only (BMI: -0.15 [-0.22; -0.08]; WC: -0.62 [-0.88; -0.37]); age and lifestyle factors (BMI: -0.12 [-0.21; -0.04]); WC: -0.016 [-0.92; -0.29], age and occupational factors (BMI: -0.20 [-0.22; 0.08]; WC: -0.62 [-0.88; -0.36]), and age and psychological factors (BMI: -0.15 [-0.22; -0.07]; WC: -0.59 [-0.86; -0.33]). Among men, shorter sleep was also longitudinally associated with higher CMD risk scores in models adjusted for age and lifestyle factors (CMD: -0.12 [-0.20; -0.04]) and age and psychological factors (CMD: -0.08 [-0.15; -0.01]). CONCLUSION: Corporate executives who report shorter sleep durations may present with poorer CMD risk profiles, independent of age, lifestyle, occupational and psychological factors. Addressing sleep health in workplace health programmes may help mitigate the development of CMD in such employees.

Sleep quality and quantity determined by polysomnography in mechanically ventilated critically ill patients randomized to dexmedetomidine or placebo.

BACKGROUND: Abnormal sleep is commonly observed in the ICU and is associated with delirium and increased mortality. If sedation is necessary, it is often performed with gamma-aminobutyric acid agonists such as propofol or midazolam leading to an absence of restorative sleep. We aim to evaluate the effect of dexmedetomidine on sleep quality and quantity. METHODS: Thirty consecutive patients were included. The study was conducted as a double-blinded, randomized, placebo-controlled trial with two parallel groups: 20 patients were treated with dexmedetomidine, and 10 with placebo. Two 16 h of polysomnography recordings were done for each patient on two consecutive nights. Patients were randomized to dexmedetomidine or placebo after the first recording, thus providing a control recording for all patients. Dexmedetomidine was administered during the second recording (6 p.m.-6 a.m.). OBJECTIVE: To compare the effect of dexmedetomidine versus. placebo on sleep - quality and quantity. PRIMARY OUTCOME: Sleep quality, total sleep time (TST), Sleep efficiency (SE), and Rapid Eye Movement (REM) sleep determined by Polysomnography (PSG). SECONDARY OUTCOME: Delirium and daytime function determined by Confusion Assessment Method of the Intensive Care Unit and physical activity. Alertness and wakefulness were determined by RASS (Richmond Agitation and Sedation Scale). RESULTS: SE were increased in the dexmedetomidine group by; 37.6% (29.7;45.6 95% CI) versus 3.7% (-11.4;18.8 95% CI) (p < .001) and TST were prolonged by 271 min. (210;324 95% CI) versus 27 min. (-82;135 95% CI), (p < .001). No significant difference in REM sleep, delirium physical activity, or RASS score was found except for RASS night two. CONCLUSION: Total sleep time and sleep efficiency were significantly increased, without elimination of REM sleep, in mechanically ventilated ICU patients randomized to dexmedetomidine, when compared to a control PSG recording performed during non-sedation/standard care.

Bedtime procrastination mediates the relation between anxiety and sleep problems.

The prevalence of sleep problems is high in primary care patients and in anxious individuals. This study assessed whether total sleep time and bedtime procrastination mediated the association between anxiety and sleep problems. We predicted higher anxiety would be negatively associated with total sleep time and positively associated with bedtime procrastination and sleep problems, and these variables would statistically mediate the association between anxiety and sleep problems. Participants were 308 adult primary care patients, predominantly female (non-Hispanic White = 158, Latinx = 111, mean age = 33.30), who initiated behavioral health services at an integrated primary care clinic. Patients completed a questionnaire regarding psychological health and sleep behaviors. Using structural equation modeling, we found higher anxiety related to higher sleep problems, partially mediated by bedtime procrastination but not total sleep time. This study highlights related factors like anxiety and prebedtime behaviors that may be effective treatment targets for sleep challenges.

Effect of training load on sleep parameters and biochemical fatigue markers in elite swimmers.

The effect of strenuous exercise on sleep patterns in swimmers is equivocal. Therefore, the purpose of the study was to describe possible changes in sleep parameters among elite swimmers subjected to different training loads (TL). Methods: Eighteen elite swimmers (8 females) were monitored across two high-volume preparatory 1-wk periods (P1, P2) and a lower-volume tapering 1-wk period (P3) before a major competition. Internal (the session rating of perceived exertion [sRPE]) and external TL (training duration and volume) were measured, along with several sleep indices (e.g., bedtime, get-up time, sleep time, wake after sleep onset [WASO]). Serum measurements of urea, creatine kinase (CK), testosterone and cortisol were taken before and after training sessions at the beginning (Mondays) and end (Fridays) of each micro cycle. Athlete TL decreased significantly in a stepwise manner from P1 to P2 and from P2 to P3. Of all sleep parameters, only significant differences in bedtime and get-up time emerged (P3 > P1 and/or P2). Sleep duration (~6.3 h) or quality (WASO: 41-45 min) were also unaffected by TL. CK levels declined from P1 to P3 (d = -0.8), and from P2 to P3 (d = -0.6). Positive exercise-induced changes in CK were also seen in each training period. The other biomarkers did not show the same temporal or acute patterns. Irrespective of the TL, the monitored swimmers experienced insufficient and fragmented sleep across this study. Neither sleep quality nor quantity were affected by different magnitudes of TL. Among the biochemical markers of fatigue, baseline plasma CK activity best reflected the physiological response to TL.

Association of job strain with accelerometer-based sleep duration and timing of sleep among older employees.

Job strain has been associated with poor sleep quality and could lead to changes in duration and timing of sleep as well. This study examined the association of job strain with sleep duration, bedtimes and awakening times among public sector employees close to their retirement age. Differences in these sleep parameters between workdays and free days across job strain groups were examined. Duration and timing of sleep were measured repeatedly with accelerometers among 466 public sector employees in Finland (mean age 63 years, 86% women), who contributed to 759 measurements in total. Job demands (low/high) and control (low/high) measured by self-reports and job exposure matrix were used to identify low strain (low demand, high control), passive (low, low), active (high, high) and high strain (high, low) jobs. No differences in sleep duration were observed on workdays, whereas on free days those in the high strain group had longer sleep duration than those in the low strain and passive job groups. The high strain group also extended their sleep from workdays to free days more, the extension being on average 59 min (95% CI 42 min-75 min) when adjusted for several sociodemographic, work and health factors. This extension of sleep duration resulted mostly from a greater delay of awakening times from workdays to free days. Psychosocial work factors, such as job strain, need to be considered when promoting sufficient sleep duration among older employees, as those with job strain may have a greater need for recovery and sleep.

Sleep duration and problem behaviour in 8-year-old children in the Childhood Obesity Project.

There is growing evidence that insufficient sleep has negative effects on the mental health of children. The aim of this study is to examine the associations between device-measured sleep duration and internalizing and externalizing problems in 8-year-old children. The study is a secondary analysis of data from the Childhood Obesity Project conducted in five European countries. Nocturnal sleep duration was measured with the SenseWear™ Armband 2. Parents rated their child's internalizing and externalizing problems on the Child Behaviour Checklist. Behaviour scores were dichotomized at the 90th percentile based on sex- and country-specific z-scores. Logistic regression models were applied to test the associations between sleep duration and behaviour. Data were available for 406 8-year-old children. The average sleep duration was 9.25 h per night (SD: 0.67) with 1464 nights measured in total. The sleep duration recommendation of the American Academy of Sleep Medicine for school-aged children (9-12 h) was met by 66.7% of children. One hour of additional sleep per night significantly reduced the risk of having internalizing problems (adjusted OR = 0.51; 95% CI 0.29-0.91). Children who adhered to the sleep duration recommendation had a lower risk for internalizing problems (adjusted OR = 0.45; 95% CI 0.21-0.99). Sleep duration and externalizing problems showed no significant association. Longer sleep duration was associated with a reduced risk of having internalizing problems but not externalizing problems. Results highlight that it is important to ensure adequate sleep duration throughout primary-school years for the optimal emotional health of children. Trial registration number: NCT00338689. Registered: June 19, 2006.

A Validation of Six Wearable Devices for Estimating Sleep, Heart Rate and Heart Rate Variability in Healthy Adults.

The primary aim of this study was to examine the validity of six commonly used wearable devices, i.e., Apple Watch S6, Garmin Forerunner 245 Music, Polar Vantage V, Oura Ring Generation 2, WHOOP 3.0 and Somfit, for assessing sleep. The secondary aim was to examine the validity of the six devices for assessing heart rate and heart rate variability during, or just prior to, night-time sleep. Fifty-three adults (26 F, 27 M, aged 25.4 ± 5.9 years) spent a single night in a sleep laboratory with 9 h in bed (23:00-08:00 h). Participants were fitted with all six wearable devices-and with polysomnography and electrocardiography for gold-standard assessment of sleep and heart rate, respectively. Compared with polysomnography, agreement (and Cohen's kappa) for two-state categorisation of sleep periods (as sleep or wake) was 88% (κ = 0.30) for Apple Watch; 89% (κ = 0.35) for Garmin; 87% (κ = 0.44) for Polar; 89% (κ = 0.51) for Oura; 86% (κ = 0.44) for WHOOP and 87% (κ = 0.48) for Somfit. Compared with polysomnography, agreement (and Cohen's kappa) for multi-state categorisation of sleep periods (as a specific sleep stage or wake) was 53% (κ = 0.20) for Apple Watch; 50% (κ = 0.25) for Garmin; 51% (κ = 0.28) for Polar; 61% (κ = 0.43) for Oura; 60% (κ = 0.44) for WHOOP and 65% (κ = 0.52) for Somfit. Analyses regarding the two-state categorisation of sleep indicate that all six devices are valid for the field-based assessment of the timing and duration of sleep. However, analyses regarding the multi-state categorisation of sleep indicate that all six devices require improvement for the assessment of specific sleep stages. As the use of wearable devices that are valid for the assessment of sleep increases in the general community, so too does the potential to answer research questions that were previously impractical or impossible to address-in some way, we could consider that the whole world is becoming a sleep laboratory.

Sleep problems are related to commuting accidents rather than to workplace accidents.

BACKGROUND: This study aimed to verify the relationships between sleep problems and both commuting and workplace accidents in workers of both sexes. METHODS: The study was carried out with a sample of workers (n = 2993; 50.2% female) from the Chilean Quality of Life Survey (ENCAVI) 2015-2016, while the rates of both workplace and commuting accidents were extracted from the statistics of the Superintendence of Social Security (SUSESO 2015; 180,036 and 52,629 lost-time accidents, respectively). RESULTS: Chilean workers sleep less than the rest of the people in the country (MW = 7.14 vs. MO = 7.33; t (6789) = - 5.19; p < .001), while the Chilean people as a whole sleep less compared to those of other countries (7.24 h per day). Likewise, it was found that sleep problems are more strongly related to commuting than to workplace accidents. In this vein, sleep quantity can explain 24% of the variance in commuting accidents' rates (Stepwise Method; R2 = .30, F (1.14) = 5.49, p < .05; ß = -.55, p < .05), by using aggregated data with all types of commuting roles (driver of a vehicle, a passenger of public or private transport, or as a pedestrian). CONCLUSIONS: Our findings show that sleep quantity has a more robust relationship with commuting than workplace accidents, a neglected issue so far. Future prevention programs should emphasize sleep hygiene and focus on commuting to and from work.

Association between self-reported sleep duration and cardiometabolic risk in corporate executives.

PURPOSE: This cross-sectional study aimed to compare the association between self-reported sleep duration and cardiometabolic risk among men and women corporate executives and investigate potential lifestyle, work- and stress-related mediators thereof. METHODS: Self-reported sleep duration and lifestyle, occupational, psychological and measured anthropometrical, blood pressure (BP) and blood marker variables were obtained from health risk assessment data of 3583 corporate executives. Sex-stratified regression analyses investigated the relationships between occupational and psychological variables with self-reported sleep duration, and sleep duration with individual cardiometabolic risk factors. Mediation analyses investigated the effects of work, psychological and lifestyle factors on the relationships between self-reported sleep duration and cardiometabolic risk factors, as well as a continuous cardiometabolic risk score calculated from the sum of sex-stratified z-standardized scores of negative fasting serum HDL, and positive plasma Glu, serum TG, body mass index (BMI), waist circumference, systolic and diastolic BP. RESULTS: Longer work hours and work commute time, depression, anxiety and stress were associated with shorter sleep duration in both men and women (all p < 0.05). Shorter sleep duration was associated with higher BMI, larger waist circumference and greater cardiometabolic risk scores in both men and women (all p < 0.05), higher diastolic BP in men (p < 0.05) and lower HDL cholesterol in women (p < 0.05). Physical activity, working hours and stress significantly mediated the relationships between self-reported sleep duration and BMI, waist circumference, diastolic BP and cardiometabolic risk score in men only. CONCLUSION: In these corporate executives, shorter self-reported sleep duration is associated with poorer psychological, occupational and cardiometabolic risk outcomes in both men and women. Given that physical activity, working hours and stress mediate this association among the men, the case for sleep health interventions in workplace health programmes is warranted.

Exercise training improves sleep quality: A randomized controlled trial.

BACKGROUND: Exercise holds promise as a non-pharmacological intervention for the improvement of sleep quality. Therefore, this study investigates the effects of different training modalities on sleep quality parameters. MATERIAL & METHODS: A total of 69 (52.7% women) middle-aged sedentary adults were randomized to (a) control group, (b) physical activity recommendation from the World Health Organization, (c) high-intensity interval training (HIIT) and (d) high-intensity interval training group adding whole-body electromyostimulation training (HIITEMS). Sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI) scale and accelerometers. RESULTS: All intervention groups showed a lower PSQI global score (all P < .022). HIIT-EMS group improved all accelerometer parameters, with higher total sleep time and sleep efficiency, and lower wake after sleep onset (all P < .016). No differences were found between groups in any sleep quality parameter. CONCLUSION: In conclusion, exercise training induced an improvement in subjective sleep quality in sedentary middleaged adults. Moreover, HIIT-EMS training showed an improvement in objective sleep quality parameters (total sleep time, sleep efficiency and wake after sleep onset) after 12 weeks of exercise intervention. The changes observed in the HIIT-EMS group were not statistically different to the other exercise modalities.

Effects of physical activity programs on sleep outcomes in older adults: a systematic review.

BACKGROUND: One in two older adults report sleep problems, which not only cause fatigue, but also negatively affect general functioning, activities of daily living, and physical and mental health. Although it is known that physical activity is positively associated with sleep in older adults, the effects of physical activity programs on sleep in older adults has not been reviewed. The aim of this systematic review was to systematically review the effects of physical activity programs on sleep in generally healthy older adults aged 60+ years. METHODS: Searches were performed in PubMed, Embase, Web of Science, SPORTDiscus, PEDro and CINAHL. The methodological quality of the included studies was rated using the 'Quality Assessment Tool for Quantitative Studies'. Only studies of moderate and strong quality were included. This review was registered in PROSPERO (CRD42018094007). RESULTS: Fourteen studies met the inclusion criteria (six randomised controlled trials and eight pretest-posttest studies). Of these studies, five were moderate and nine were strong quality studies. Mean age of study samples ranged from 64 to 76 years. Exercise programs included various activities aimed at improving mobility, endurance and strength. Intervention duration ranged from 2 weeks to 12 months. Eleven studies used subjective measures of sleep, two used objective measures and one used both. Sixteen different sleep outcomes were reported. All but one study, found at least one significant improvement on sleep outcomes. No significantly detrimental effects were reported. Effect sizes, calculated in ten studies, ranged from 0,34-1,55 and were substantial (≥0,8) in four studies. CONCLUSIONS: This systematic review suggests that exercise programs positively affect various aspects of sleep in generally healthy older adults. More specifically, moderate intensity exercise programs, with a frequency of three times per week and a duration of 12 weeks up to 6 months, showed the highest number of significant improvements in different sleep outcomes in older adults. Furthermore, programs that offered single exercise types, such as Baduanjin, Tai chi and the silver yoga program, or a combination of exercises showed the highest proportion of significant versus reported effects on sleep outcomes.

Association between sleep disorder and quality of life in patients with type 2 diabetes: a cross-sectional study.

BACKGROUND: We investigated the association between sleep symptoms, which cause sleep disorder, and quality of life (QoL) among people with type 2 diabetes (T2D). METHODS: In this cross-sectional study of 342 people with T2D, the Japan National Health and Wellness Survey (NHWS) database 2016 were used. We treated the respondents who reported experiencing any of the sleep symptoms as having sleep disorders. To examine health-related QoL (HRQoL), we used the physical component summary (PCS) and the mental component summary (MCS) from the 36-Item short-form and the EuroQol 5 Dimension (EQ-5D) survey instruments. Overall activity impairment was used for assessment of the effect on the individual's ability to perform regular daily activities. We used t-test and one-way ANOVA test for comparison QoL scores between the participants with and without sleep disorders. RESULTS: 66.4% of the participants with T2D reported having a sleep disorder. The PCS, MCS, EQ-5D, and overall activity impairment of people with sleep disorder was significantly poorer than those of the people without. Specific sleep symptoms, such as waking up to go to the bathroom, daytime sleepiness, and waking up too early (before the alarm clock), had high prevalence (35.4, 27.8 and 20.2%). The participants who experienced waking up to go to the bathroom or daytime sleepiness demonstrated significantly poorer QoL on all scores related to QoL, but those who experienced waking up too early only demonstrated significantly poorer QoL on the EQ-5D. CONCLUSIONS: Two-thirds of people with T2D in this study suffer from sleep disorders. The people who experience waking up to go to the bathroom or daytime sleepiness had significantly poorer QoL than those without these symptoms. Thus, sleep disorders, especially the symptoms of waking up to go to the bathroom or daytime sleepiness, might be the treatment targets for QOL of people with T2DM.

A validation study of the WHOOP strap against polysomnography to assess sleep.

The aim of the study was to compare the WHOOP strap - a wearable device that estimates sleep based on measures of movement and heart rate derived from actigraphy and photoplethysmography, respectively. Twelve healthy adults (6 females, 6 males, aged 22.9 ± 3.4 years) participated in a 10-day, laboratory-based protocol. A total of 86 sleeps were independently assessed in 30-s epochs using polysomnography and WHOOP. For WHOOP, bed times were entered by researchers and sleeps were scored by the company based on proprietary algorithms. WHOOP overestimated total sleep time by 8.2 ± 32.9 minutes compared to polysomnography, but this difference was non-significant. WHOOP was compared to polysomnography for 2-stage (i.e., wake, sleep) and 4-stage categorisation (i.e., wake, light sleep [N1 or N2], slow-wave sleep [N3], REM) of sleep periods. For 2-stage categorisation, the agreement, sensitivity to sleep, specificity for wake, and Cohen's kappa were 89%, 95%, 51%, and 0.49, respectively. For 4-stage categorisation, the agreement, sensitivity to light sleep, SWS, REM, and wake, and Cohen's kappa were 64%, 62%, 68%, 70%, 51%, and 0.47, respectively. In situations where polysomnography is impractical (e.g., field settings), WHOOP is a reasonable method for estimating sleep, particularly for 2-stage categorisation, if accurate bedtimes are manually entered.

Actigraphy-based sleep analysis in sedentary and overweight/obese adults with primary hypertension: data from the EXERDIET-HTA study.

PURPOSE: The aim of this study was to analyze actigraphy-based sleep quantity and quality in sedentary and overweight/obese adults with primary hypertension (HTN) divided by sex and cardiorespiratory fitness (CRF) and to assess the association of sleep parameters with body composition, blood pressure (BP), and CRF. METHODS: This is a cross-sectional design utilizing data from the EXERDIET-HTA study conducted in 154 non-physically, obese adults with HTN (53.3 ± 7.8 years). Sleep parameters (total bedtime; total sleep time, TST; and sleep efficiency = (TST/total bedtime) × 100)) were calculated from raw accelerometer data (ActiGraph GT3X+). Peak oxygen uptake (V̇O2peak) determined the CRF. Blood pressure was assessed with the 24-h ambulatory BP monitoring. The distributions of V̇O2peak were divided into tertiles (low, medium, and high CRF) in each sex. Series of linear regression analyses were conducted between sleep, fitness, and health-related variables. RESULTS: Short sleep duration (6.2 h) both on weekdays and weekends, poor sleep quality (< 85% of efficiency), and no significant differences in sleep variables between women and men, nor among CRF groups, were observed. The short sleeping pattern was negatively associated (P < 0.05) with mean and night systolic BP (mmHg, ß = - 0.2), and sleep efficiency with waist circumference (cm, ß = - 0.08, P = 0.05). CONCLUSIONS: Actigraphy-based sleep analysis reinforces that sleep disorders, such as short sleep duration and poor sleep quality, are associated with high BP and abdominal obesity in sedentary adults with overweight/obesity and HTN. Sleep pattern did not appear to be related with CRF level in this population.

Sleep, low self-control, and deviance: Direct and indirect links across immigrant groups and socioeconomic strata.

Sleep functioning is concurrently and longitudinally associated with norm-violating behaviors; however, the specific correlates contributing to these links remain unknown. Moreover, despite known mean-level differences in sleep functioning across immigrant and non-immigrant youth as well as socioeconomic strata, it is largely unknown whether links between sleep and norm-violating behaviors vary across groups. The current study tested the direct effects of sleep problems and sleep quantity on measures of deviance, as well as the indirect links via low self-control. It also tested moderating effects by immigrant and SES groups, indicated by parental education, on the associations and mean-level differences in sleep functioning. Results from structural equation models based on cross-sectional data from a national probability sample of Swiss adolescents (N = 6,866) provided evidence of both direct as well as indirect links between sleep and deviance, via low self-control. Despite mean-level differences, the tested links were invariant across immigrant and SES groups, with one modest exception in the magnitude of effect.

Effects of Natural Between-Days Variation in Sleep on Elite Athletes' Psychomotor Vigilance and Sport-Specific Measures of Performance.

Performance capacity in athletes depends on the ability to recover from past exercise. While evidence suggests that athletic performance decreases following (partial) sleep deprivation and increases following sleep extension, it is unclear to which extent natural variation in sleep impacts performance. Sleep quantity and, for the first time, sleep stages were assessed among 98 elite athletes on three non-consecutive nights within a 7-day monitoring period, along with performance tests that were taken on standardized times each following morning. Performance assessment included psychomotor performance (10-minute psychomotor vigilance task) and sport-specific tests of fine (e.g., accuracy) and gross motor skills (e.g., endurance, power). Mixed-effects models were employed to assess the effect of sleep quantity (total sleep time (TST), sleep onset latency (SOL), wake after sleep onset, sleep efficiency) and sleep stage duration (light, deep, REM) on performance. Average TST was 7:30 ± 1:05 hours, with a mean variation of 57 minutes across days. Longer TSTs were associated with faster reaction times (p = 0.04). Analyses indicated small and inconsistent effects of sleep quantity (TST, SOL) and sleep staging (light sleep) on gross motor performance, and no effects on fine motor skill performance. Results indicate that natural variation in sleep quantity impacts psychomotor vigilance to a greater extent than athletic performance. Small or absent effects can be a consequence of the rather small variation in non-manipulated sleep. It is suggested that one night of compromised sleep may not be immediately problematic, but that more extreme sleep loss or accumulated sleep debt may have more severe consequences.

Actigraphic sleep measures and diet quality in the Hispanic Community Health Study/Study of Latinos Sueño ancillary study.

Using a cross-sectional probability sample with actigraphy data and two 24-h dietary recalls, we quantified the association between sleep duration, continuity, variability and timing with the Alternative Healthy Eating Index-2010 diet quality score and its components in 2140 Hispanic Community Health Study/Study of Latinos participants. The Alternative Healthy Eating Index diet quality-2010 score ranges from 0 to 110, with higher scores indicating greater adherence to the dietary guidelines and lower risk from major chronic disease. None of the sleep measures was associated with total caloric intake as assessed using dietary recalls. However, both an increase in sleep duration and sleep efficiency were associated with healthier diet quality. Each standard deviation increase in sleep duration (1.05 h) and sleep efficiency (4.99%) was associated with a 0.30 point increase and 0.28 point increase, respectively, in the total Alternative Healthy Eating Index-2010 score. The component of Alternative Healthy Eating Index-2010 most strongly associated with longer sleep duration was increased nuts and legumes intake. The components of Alternative Healthy Eating Index-2010 most strongly associated with higher sleep efficiency were increased whole fruit intake and decreased sodium intake. Both longer sleep duration and higher sleep efficiency were significantly associated with better diet quality among US Hispanic/Latino adults. The dietary components most strongly associated with sleep duration and sleep efficiency differed, suggesting potentially independent mechanisms by which each aspect of sleep impacts dietary choices. Longitudinal research is needed to understand the directionality of these identified relationships and the generalizability of these data across other ethnic groups.

Contributing influences of work environment on sleep quantity and quality of nursing assistants in long-term care facilities: A cross-sectional study.

The effect of shift work on nurses' sleep is well-studied, but there are other challenging aspects of health care work that might also affect the sleep of direct caregivers. This study examined the influence of the long-term care work environment on sleep quantity and quality of nursing assistants. A cross-sectional survey collected data from 650 nursing assistants in 15 long-term care facilities; 46% reported short sleep duration and 23% reported poor sleep quality. A simple additive index of the number of beneficial work features (up to 7) was constructed for analysis with Poisson regression. With each unit increase of beneficial work features, nursing assistants were 7% less likely to report short sleep duration and 17% less likely to report poor sleep quality. These results suggest that effective workplace interventions should address a variety of work stressors, not only work schedule arrangements, in order to improve nursing assistants' sleep health.