Validation of self-reported sleep against actigraphy

Are nocturnal awakenings at age 1 predictive of sleep duration and efficiency at age 6: Results from two birth cohorts

Objective

To investigate the association of nighttime awakenings at 12 months with the duration and efficiency of nighttime sleep at 6 years of age.

Methods

Data from two population-based prospective studies (The Pelotas 2004 and The Pelotas 2015 Birth Cohorts) were used. Information on nighttime awakenings was provided by mothers during the 12-month follow-up interview. Infants who awakened >3 times after sleep onset at 12 months were considered frequent wakeners. Sleep duration and sleep efficiency were obtained by actigraphy at the 6-year follow-up. Children wore the device at the wrist of the non-dominant arm continuously for 3-7 days, including at least one weekend day. Unadjusted and adjusted beta coefficients were obtained by linear regression for each cohort separately.

Results

2500 children from the 2004 and 2793 from the 2015 cohort had full information on nighttime awakenings at 12 months and actigraphy at 6 years and were analyzed. Prevalence of frequent wakeners was 6.3 % and 5.9 % in the 2004 and 2015 cohort, respectively. Mean bedtime and wake-up time at 6 years were, respectively, 23:23 and 08:41 h in the 2004 cohort, and 00:10 and 09:00 h int the 2015 cohort. Nighttime sleep lasted on average 7.54 and 7.24 h respectively in the 2004 and the 2015 cohort, and the sleep efficiency was 81.1 and 82.5 % respectively. In adjusted analyses, no associations were found between awakening at 12 months and sleep duration or sleep efficiency at 6 years of age.

Conclusion

In both cohorts sleep duration and efficiency were below the recommendation for school-age children (respectively 9-11 h and 85 %). There was no relationship between the number of nighttime awakenings at 12 months and sleep duration or efficiency at 6 years.

Negative health outcomes in long sleepers: The societal sleep restriction hypothesis

Society imposes work and school schedules, as well as social expectations, that militate against consistently obtaining more than 7-9 h of sleep every 24 h. For most but not all adults this sleep duration is adequate. But among those who consistently obtain more than 9 h of sleep per day ("long sleepers"), there likely exists a subpopulation of individuals who are nevertheless failing to obtain enough sleep to satisfy their physiological sleep needs - a consequence of "restricting" their daily sleep durations to whatever extent they can tolerate so as to conform as closely as possible to society's norms and expectations. It is hypothesized that the 'long sleep arm' of the seemingly paradoxical U-shaped relationship between sleep duration and negative health outcomes can be explained, at least in part, by the existence of a subpopulation of such 'sleep-restricted long sleepers.'

Inequities in sleep duration and quality among adolescents in Canada

BACKGROUND

Several recent global events may have impacted adolescent sleep and exacerbated pre-existing disparities by social positions (i.e., social roles, identity or sociodemographic factors, and/or group memberships that are associated with power and oppression due to the structures and processes in a given society at given time). Current understanding of sleep among adolescents is critical to inform interventions for a more equitable future, given the short and long-term consequences of inadequate sleep on health and well-being. This study aimed to provide contemporary evidence on sleep disparities by key social positions among adolescents in Canada.

METHODS

Cross-sectional analyses were conducted using self-reported data collected during 2020-2021 (the first full school year after the COVID-19 pandemic onset) from 52,138 students (mean [SD] age = 14.9 [1.5]) attending 133 Canadian secondary schools. Multiple regression models were used to test whether sleep quality (how well students slept during past week), duration (weekday, weekend, weighted daily average), and guideline adherence (8-10 h/day) differed by sex and gender, race and ethnicity, and socioeconomic status (SES).

RESULTS

Females reported a mean [95% CI] difference of -1.7 [-3.7, 0.4] min/day less sleep on weekdays than males, but 7.1 [4.5, 9.6] min/day more sleep on weekends, resulting in no difference in average daily sleep between males and females. Females were less likely to report good quality sleep compared to males (AOR = 0.57 [0.54, 0.60]). SES followed a generally monotonic trend where higher scores were associated with more sleep on weekdays (Δhighest: lowest = -28.6 [-39.5, -17.6]) and weekends (Δhighest: lowest = -17.5 [-3.8, -31.2]) and greater likelihood of higher sleep quality (AORhighest: lowest = 3.04 [2.35, 3.92]). Relative to White adolescents, weekday and average daily sleep duration were lower among all other racial identities; mean differences ranged from ∼ 5-15 min/day, with Black students reporting the least sleep.

CONCLUSIONS

Differences in sleep duration and quality were most profound among adolescents from the lowest and highest SES. Racial disparities were more evident on weekdays. Compensatory weekend sleep appears more pronounced in females than males. Addressing sleep inequities is critical, as a robust predictor of multiple health outcomes.

Mental health, substance use, and a composite of sleep health in adults, 2018 Ohio behavioral risk factor surveillance system

OBJECTIVES

Various factors impact sleep health including mental health and substance use. Mental health issues and substance use continue to rise in the United States. Yet, the association between mental health, substance use and sleep health in adults remains unclear.

METHODS

We used multivariable linear regression models to examine the associations between mental health (poor mental health days in the past 30 days) and substance use (marijuana, tobacco, alcohol) with sleep health (individual dimensions of sleep: alertness, sleep efficiency, duration, and sleep health composite score) in 4333 participants from the 2018 Ohio Behavioral Risk Factor Surveillance System Survey.

RESULTS

Better mental health was associated with higher alertness, higher sleep efficiency, longer sleep duration and a higher sleep health composite score even after controlling for covariates (individual: sex at birth, age, body mass index, race, education, sleep disordered breathing, and area-level: socioeconomic deprivation) (all p < .001). Higher marijuana and tobacco use were associated with lower individual sleep health dimensions (marijuana with sleep efficiency and duration and tobacco use with lower efficiency) and a lower sleep health composite score even after controlling for covariates for tobacco use (p < .001). Contrary to the hypothesis, higher alcohol use was associated with higher alertness and a higher sleep health composite score (p < .001), however after adjusting for covariates these associations were no longer significant.

CONCLUSIONS

The implications of these trends on sleep health are important to address as mental health and substance use are modifiable targets to consider when addressing sleep health.

Sleep as a contributor to socioeconomic disparities in hypertension: The Midlife in the United States (MIDUS II) Study

STUDY OBJECTIVES

Hypertension is highly prevalent and is a major risk factor for cardiovascular disease. There is a higher burden of hypertension among individuals of lower socioeconomic status (SES), yet the role of sleep in understanding socioeconomic disparities in hypertension is unclear. We investigated whether sleep quality is a partial mediator of the association between SES and hypertension.

METHODS

We used data from the Midlife in the United States II Study, 2004-2009 (n = 426). Analyses were conducted in 2023. Participants underwent 7-day actigraphy and clinical assessments. Sleep quality measures included actigraphy-defined wakefulness after sleep onset (WASO) and sleep efficiency. Hypertension was measured via three consecutive blood pressure readings, and SES was measured via educational attainment. Models were fit adjusting for age, gender, race, body mass index, and perceived stress.

RESULTS

Participants had a mean age of 53.5 years (SD = 12.4) and 41.0% were African American. The prevalences of poor WASO (>30 minutes), low sleep efficiency (<85%), and hypertension were 77.7%, 67.1%, and 61.0%, respectively. Education was not associated with hypertension. However, individuals with low vs. high sleep efficiency had 24% higher prevalence of hypertension (aPR = 1.24, 95% CI: 1.02 to 1.51), higher systolic blood pressure (aβ = 4.61, 95% CI: 0.69 to 8.53), and higher diastolic blood pressure (aβ = 2.50, 95% CI: 0.10 to 4.89). Education was not significantly associated with sleep after adjustment. There was no evidence of sleep mediating the SES-hypertension relation.

CONCLUSIONS

Effective interventions to lower hypertension prevalence should consider targeting sleep quality. Future research should explore the intersectionality of SES and race in hypertension.

From the Workroom to the Bedroom: Work-to-Home Spillover as a Mechanism Linking Work Characteristics to Sleep Health

Work may influence the home domain and subsequently impact employee sleep. Past work found that negative spillover mediated the relationship between perceived unfairness about work and insomnia symptoms across 20 years. As an extension of past work, this study investigated whether negative spillover and positive spillover mediate the relationship between job demands (perceived unfairness, job discrimination) and job resources (coworker and supervisor support) on multidimensional sleep health. Two waves of survey data from a subset of full-time workers were obtained from the Midlife in the United States Study approximately 10 years apart. A sleep health composite captured irregularity, dissatisfaction, nap frequency, inefficiency, and suboptimal sleep duration (higher=more sleep health problems). PROCESS Macro evaluated cross-sectional (T1) and sequential (T1 exposureàT1 mediatoràT2 outcome) mediation pathways, adjusting for sociodemographic characteristics, physical health, neuroticism, and work hours. Both cross-sectionally and prospectively, higher negative spillover mediated the association of higher unfairness with more sleep health problems, and the association between higher discrimination and more sleep health problems. There was no support for positive spillover as a mediator between job resources and sleep health cross-sectionally or prospectively. Findings suggest that organizations should reduce the amount of negative spillover by limiting instances of unfairness and discrimination at work to promote specific aspects of employee sleep health such as sleep irregularity, dissatisfaction, efficiency, and nap frequency.

Understanding resilience: Lifestyle-based behavioral predictors of mental health and well-being in community-dwelling older adults during the COVID-19 pandemic

BACKGROUND

Changes in sleep, physical activity and mental health were observed in older adults during early stages of the COVID-19 pandemic. Here we describe effects of the COVID-19 pandemic on older adult mental health, wellbeing, and lifestyle behaviors and explore predictors of better mid-pandemic mental health and wellbeing.

METHODS

Participants in the Adult Changes in Thought study completed measures of lifestyle behaviors (e.g., sleep, physical activity) and mental health and wellbeing both pre-pandemic during regular study visits and mid-pandemic via a one-time survey. We used paired t-tests to compare differences in these measures pre- vs. mid-pandemic. Using multivariate linear regression, we further explored demographic, health, and lifestyle predictors of pandemic depressive symptoms, social support, and fatigue. We additionally qualitatively coded free text data from the mid-pandemic survey for related comments.

RESULTS

Participants (N = 896) reported significant changes in mental health and lifestyle behaviors at pre-pandemic vs. mid-pandemic measurements (p < 0.0001). Qualitative findings supported these behavioral and wellbeing changes. Being male, never smoking, and lower pre-pandemic computer time and sleep disturbance were significantly associated with lower pandemic depressive symptoms. Being partnered, female, never smoking, and lower pre-pandemic sleep disturbance were associated with higher pandemic social support. Pre-pandemic employment, more walking, less computer time, and less sleep disturbance were associated with less pandemic fatigue. Participant comments supported these quantitative findings, highlighting gender differences in pandemic mental health, changes in computer usage and physical activity during the pandemic, the value of spousal social support, and links between sleep disturbance and mental health and wellbeing. Qualitative findings also revealed additional factors, such as stresses from personal and family health situations and the country's concurrent political environment, that impacted mental health and wellbeing.

CONCLUSIONS

Several demographic, health, and lifestyle behaviors appeared to buffer the effects of the COVID-19 pandemic and may be key sources of resilience. Interventions and public health measures targeting men and unpartnered individuals could promote social support resilience, and intervening on modifiable behaviors like sleep quality, physical activity and sedentary activities like computer time may promote resilience to fatigue and depressive symptoms during future community stressor events. Further research into these relationships is warranted.

Associations of dietary patterns with objective and subjective sleep duration and sleep quality in a population-based cohort study

OBJECTIVE

To examine cross-sectional and longitudinal associations of various types of dietary patterns with self-reported sleep quality and with actigraphy-estimated sleep parameters in the prospective, population-based Rotterdam Study.

METHODS

For each participant, scores for five different dietary patterns were derived based on food frequency questionnaires; two pre-defined scores developed to estimate adherence to the Dutch dietary guidelines and to the Mediterranean diet; and three data-driven scores indicating a prudent, unhealthy and typical Dutch diet. In 2589 participants (median age 56.9 years; 58 % female), self-rated sleep quality was assessed with the Pittsburgh Sleep Quality Index. In 533 participants, actigraphs were worn for an average of 6.8 days (SD: 0.7) to estimate total sleep time, sleep onset latency, wake after sleep onset, and sleep efficiency. Sleep parameters were measured at baseline and 3-6 years later. Multiple linear regression was used to assess cross-sectional and longitudinal associations.

RESULTS

No statistically significant associations between dietary patterns and total sleep time, sleep onset latency, wake after sleep onset, sleep efficiency and subjective sleep quality were observed in cross-sectional or longitudinal analyses. To illustrate, the effect estimate for sleep duration was 2.7 min per night (95 % CI -2.1, 7.5) per 5 point increase in Mediterranean diet score in the cross-sectional analyses. Furthermore, in longitudinal analyses, the effect estimate for sleep duration was -1.0 min per night (95 % CI -5.2, 3.1) per SD increase in the prudent diet.

CONCLUSIONS

Our results suggest that dietary patterns are not associated with sleep in this population-based cohort study.

TRIAL REGISTRATION

Netherlands National Trial Register and WHO International Clinical Trials Registry Platform (ICTRP; https://apps.who.int/trialsearch/) shared catalogue number NL6645/NTR6831. Registered November 13th, 2017.

To sleep or to breastfeed: Associations between feeding method and sleep in infants and children

AIM

This study aimed to understand the association between feeding method, specifically breastfeeding versus non-breastfeeding, at 6 and 12 months and infant sleep over the first 3 years of life.

METHODS

A sample of 444 mother-infant dyads from the Maternal Adversity, Vulnerability and Neurodevelopment cohort were analysed. Based on retrospective maternal reports between 3-24 months, infants' breastfeeding status was determined at 6 and 12 months. Nocturnal sleep duration, longest period of consecutive sleep, and total sleep over 24 h were measured by maternal reports at 6, 12, 24 and 36 months.

RESULTS

Generalized Estimating Equations revealed no significant association between feeding status, both at 6 and 12 months, and nocturnal sleep duration or total sleep over 24 h between 6-36 months (p > 0.05). However, breastfeeding at both 6 and 12 months was associated with shorter periods of consecutive sleep, at 6 and 12 months (p < 0.05) but not at 24 and 36 months (p > 0.05).

CONCLUSION

Our findings suggest that breastfeeding seems to be associated with more infant sleep fragmentation but not with total sleep duration in early infancy. However, this sleep fragmentation does not persist into later infancy and early toddlerhood.

Effects of exercise on sleep in patients with epilepsy: A systematic review

Exercise interventions in epilepsy have been shown to improve seizure frequency, physical capacity, quality of life, mood, and cognitive functioning. However, the effectiveness of exercise in improving sleep in epilepsy is less clear. The purpose of this report is to identify the published literature regarding exercise interventions in people with epilepsy to determine 1) what proportion of published clinical trials assess sleep as an outcome, and 2) what benefits of exercise interventions on sleep have been observed. We searched the PubMed, PsycINFO, and SCOPUS electronic databases using the search terms "epilepsy AND [exercise OR physical activity]" and identified 23 articles reporting on 18 unique clinical trials. Nine studies were conducted in adults, five in children, and four in adults and children with active seizures, controlled seizures, or both. Exercise modalities included aerobic exercise, strength training, walking, and yoga, among others, and some also included educational and motivational components. Exercise effects on sleep were tested in four studies, two of which only included indirect measures of sleep- and rest-related fatigue, with mixed results. Of the two reports assessing sleep directly, one reported marginal non-significant improvements in subjective sleep quality and no improvements in objective sleep quality in children after twelve weeks of walking, and the other reported no benefits in subjective sleep quality after twelve weeks of combined aerobic, strength, and flexibility training in adults. Given the health benefits of sleep and detrimental effects of sleep deprivation in epilepsy, epilepsy researchers need to assess the effects of exercise interventions on sleep.

Measurement of Sleep in Chronic Traumatic Brain Injury: Relationship Between Self-report and Actigraphy

OBJECTIVE

To examine the relationship between self-report and actigraphy measurement of sleep in people with and without traumatic brain injury (TBI) by addressing 2 aims: (1) to assess the relationship between self-report and actigraphy for sleep quantity in people with and without TBI; and (2) to explore how self-report and actigraphy capture sleep quality in TBI.

SETTING

Participants completed the study over 2 weeks in their own homes. They wore activity monitors, day and night, throughout the experiment and completed morning sleep diaries while interacting with an experimenter on videoconference.

PARTICIPANTS

This project was embedded in a larger study on sleep and word learning in 100 adults: 50 with chronic, moderate-severe TBI and 50 demographically matched noninjured peers. Of the 100 participants who completed the larger study, 92 participants (45 with TBI and 47 noninjured peers) had sufficient actigraphy data for inclusion in the current study.

DESIGN

We used multilevel linear regression models and correlation analyses to assess how well participants' self-report corresponded to actigraphy measurement of sleep.

MAIN MEASURES

Actigraphy measures included nightly sleep duration and nighttime wakeups. Sleep diary measures included self-reported nightly sleep duration, nighttime wakeups, sleep quality, and morning fatigue.

RESULTS

People with and without TBI did not differ in the relationship between self-reported and actigraphy measurement of sleep quantity. Performance on a neuropsychological memory assessment did not correlate with the difference in self-reported and actigraphy-measured sleep in the TBI group. Sleep characteristics that were measured by actigraphy did not predict subjective experiences of sleep quality or fatigue.

CONCLUSIONS

Short-term self-report diaries capture accurate information about sleep quantity in individuals with TBI and may support self-report of other daily habits. Future research is needed to identify reliable metrics of sleep quality, and how they relate to other domains such as memory and mood, in the chronic phase of TBI.

Validation of actigraphy sleep metrics in children aged 8 to 16 years: considerations for device type, placement and algorithms

BACKGROUND

Actigraphy is often used to measure sleep in pediatric populations, despite little confirmatory evidence of the accuracy of existing sleep/wake algorithms. The aim of this study was to determine the performance of 11 sleep algorithms in relation to overnight polysomnography in children and adolescents.

METHODS

One hundred thirty-seven participants aged 8-16 years wore two Actigraph wGT3X-BT (wrist, waist) and three Axivity AX3 (wrist, back, thigh) accelerometers over 24-h. Gold standard measures of sleep were obtained using polysomnography (PSG; Embletta MPRPG, ST + Proxy and TX Proxy) in the home environment, overnight. Epoch by epoch comparisons of the Sadeh (two algorithms), Cole-Kripke (three algorithms), Tudor-Locke (four algorithms), Count-Scaled (CS), and HDCZA algorithms were undertaken. Mean differences from PSG values were calculated for various sleep outcomes.

RESULTS

Overall, sensitivities were high (mean ± SD: 91.8%, ± 5.6%) and specificities moderate (63.8% ± 13.8%), with the HDCZA algorithm performing the best overall in terms of specificity (87.5% ± 1.3%) and accuracy (86.4% ± 0.9%). Sleep outcome measures were more accurately measured by devices worn at the wrist than the hip, thigh or lower back, with the exception of sleep efficiency where the reverse was true. The CS algorithm provided consistently accurate measures of sleep onset: the mean (95%CI) difference at the wrist with Axivity was 2 min (-6; -14,) and the offset was 10 min (5, -19). Several algorithms provided accurate measures of sleep quantity at the wrist, showing differences with PSG of just 1-18 min a night for sleep period time and 5-22 min for total sleep time. Accuracy was generally higher for sleep efficiency than for frequency of night wakings or wake after sleep onset. The CS algorithm was more accurate at assessing sleep period time, with narrower 95% limits of agreement compared to the HDCZA (CS:-165 to 172 min; HDCZA: -212 to 250 min).

CONCLUSION

Although the performance of existing count-based sleep algorithms varies markedly, wrist-worn devices provide more accurate measures of most sleep measures compared to other sites. Overall, the HDZCA algorithm showed the greatest accuracy, although the most appropriate algorithm depends on the sleep measure of focus.

Difficulties in emotion regulation moderates the relationship between mood symptoms and nightmares in an inpatient psychiatric sample

BACKGROUND

Emotional processing and regulation of affect are often impaired in psychiatric patients. Nightmares could be considered a manifestation of problems with this process. In the present study, we examined how depression, anxiety and suicidal risk related to difficulties in emotion regulation and nightmares over the course of inpatient treatment. We also explored whether emotion regulation problems moderated the relationship between changes in depression, anxiety, and suicide risk to changes in nightmares from admission to discharge.

METHODS

The present study included 1215 adults admitted to an inpatient psychiatric hospital ranging from 18 to 87 years of age (M = 37.18, SD = 16.14). Mood symptoms, emotion regulation difficulties, nightmares and suicide risk were assessed at admission and discharge. Moderation analyses were calculated using Model 1 of the PROCESS Macro (Hayes, 2013).

RESULTS

Moderation analyses showed the associations between depression and nightmares (b = 0.25, p < .001) and suicide and nightmares (b = 0.34, p < .001) were strongest when patients had high levels of emotion regulation difficulties. Emotion regulation difficulties did not, however, moderate the relationship between anxiety and nightmares. Furthermore, improvement in depression and nightmares was significantly related to improvement in emotion regulation difficulties.

LIMITATIONS

The homogeneity of the sample limits the generalizability of the results. Furthermore, the use of self-report measures, especially sleep related assessments, can bias the data more than objective measures.

CONCLUSIONS

These findings provide clinical implications when treating psychiatric patients such as a need for emotion regulation skills building.

Assessment of Nocturnal Blood Pressure: Importance of Determining the Time in Bed-A Pilot Study

Objectives: Nocturnal blood pressure (BP) monitoring is essential for evaluating cardiovascular risk and guiding treatment decisions. However, the standardized narrow-fixed nighttime period between 10 p.m. and 6 a.m. may not accurately reflect individual sleep schedules. This pilot study aimed to investigate the comparability between the standardized nighttime period and actual time in bed (TIB) regarding BP assessment. Further, our goal was to evaluate the clinical relevance of the observed BP differences. Methods: A total of 30 participants underwent 24 h ambulatory blood pressure monitoring (ABPM). Patient-specific TIB was precisely assessed through an accelerometer and a position sensor from the SOMNOtouch NIBP™ (SOMNOmedics GmbH, Randersacker, Germany). We analysed the effect of considering individual TIB as nighttime instead of the conventional narrow-fixed interval on the resulting nocturnal BP levels and dipping patterns. Results: We observed differences in both systolic and diastolic BP between the standardized nighttime period and the TIB. Furthermore, a notable percentage of patients (27%) changed their dipping pattern classification as a function of the nighttime definition adopted. We found strong correlations between the start (r = 0.75, p < 0.01), as well as the duration (r = -0.42, p = 0.02) of TIB and the changes in dipping pattern classification. Conclusions: Definition of nocturnal period based on the individual TIB leads to clinically relevant changes of nocturnal BP and dipping pattern classifications. TIB is easily detected using a body position sensor and accelerometer. This approach may thus improve the accuracy of cardiovascular risk evaluation and enhance treatment strategies.

Prospective analysis of sleep characteristics, chronotype, and risk of breast cancer in the california teachers study

PURPOSE

Poor sleep quality and evening chronotype were associated with increased risk of breast cancer in a previous retrospective study in the California Teachers Study (CTS). The present analysis examines these sleep factors prospectively in the same cohort of women.

METHODS

From the CTS, we included 1,085 incident breast cancer cases and 38,470 cancer-free participants from 2012 through 2019. We calculated time at risk and used Cox proportional hazards regression models to estimate the hazard ratios (HRs) and control for risk factors such as age, race, body mass index, family history of breast cancer, and reproductive history. The sleep factors examined were quality, latency, duration, disturbance, and sleep medication use, based on a shortened version of the Pittsburgh Sleep Quality Index, as well as chronotype (preference for morning or evening activity). This analysis was limited to women who were post-menopausal at the time they answered these sleep-related questions.

RESULTS

Measures of sleep quality did not appear to be associated with subsequent breast cancer risk. The HR for evening chronotypes compared to morning chronotypes was somewhat elevated (HR 1.19, 95% CI 1.04, 1.36).

CONCLUSION

While the measures of sleep quality and duration were not associated with post-menopausal breast cancer risk in this prospective analysis, the modestly elevated risk observed for evening chronotypes was consistent with the prior retrospective analysis.

Actigraphy-derived measures of sleep and risk of prostate cancer in the UK Biobank

BACKGROUND

Studies of sleep and prostate cancer are almost entirely based on self-report, with limited research using actigraphy. Our goal was to evaluate actigraphy-measured sleep and prostate cancer and to expand on findings from prior studies of self-reported sleep.

METHODS

We prospectively examined 34 260 men without a history of prostate cancer in the UK Biobank. Sleep characteristics were measured over 7 days using actigraphy. We calculated sleep duration, onset, midpoint, wake-up time, social jetlag (difference in weekend-weekday sleep midpoints), sleep efficiency (percentage of time spent asleep between onset and wake-up time), and wakefulness after sleep onset. Cox proportional hazards models were used to estimate covariate-adjusted hazards ratios (HRs) and 95% confidence intervals (CIs).

RESULTS

Over 7.6 years, 1152 men were diagnosed with prostate cancer. Sleep duration was not associated with prostate cancer risk. Sleep midpoint earlier than 4:00 am was not associated with prostate cancer risk, though sleep midpoint of 5:00 am or later was suggestively associated with lower prostate cancer risk but had limited precision (earlier than 4:00 am vs 4:00-4:59 am HR = 1.00, 95% CI = 0.87 to 1.16; 5:00 am or later vs 4:00-4:59 am HR = 0.79, 95% CI = 0.57 to 1.10). Social jetlag was not associated with greater prostate cancer risk (1 to <2 hours vs <1 hour HR = 1.06, 95% CI = 0.89 to 1.25; ≥2 hours vs <1 hour HR = 0.90, 95% CI = 0.65 to 1.26). Compared with men who averaged less than 30 minutes of wakefulness after sleep onset per day, men with 60 minutes or more had a higher risk of prostate cancer (HR = 1.20, 95% CI = 1.00 to 1.43).

CONCLUSIONS

Of the sleep characteristics studied, higher wakefulness after sleep onset-a measure of poor sleep quality-was associated with greater prostate cancer risk. Replication of our findings between wakefulness after sleep onset and prostate cancer are warranted.

Meaningful Within-Patient Change in Subjective Total Sleep Time in Patients with Insomnia Disorder: An Analysis of the Sleep Diary Questionnaire Using Data from Open-Label and Phase III Clinical Trials

BACKGROUND

The Sleep Diary Questionnaire (SDQ), a modified version of the Consensus Sleep Diary, is a 17-item sleep diary for assessing subjective total sleep time (sTST: total time spent asleep at night) and other sleep parameters in insomnia trials. sTST is a key parameter of efficacy in insomnia trials; however, the magnitude of improvement in this parameter that people with insomnia disorder consider clinically meaningful is unclear.

OBJECTIVE

The aim of this study was to estimate meaningful within-patient change for sTST using clinical trial data.

METHODS

Data were from an open-label trial of zolpidem and pooled data from a phase III placebo-controlled trial of daridorexant. In both trials, adults with moderate to severe insomnia completed the SDQ daily. Meaningful change in sTST was estimated in an anchor-based analysis using outcome measures that were correlated with change in weekly average sTST (Spearman correlation coefficient ≥ 0.30): the Insomnia Severity Index, patient global assessments and impressions of severity and change in daytime and night-time symptoms (PGA-S, PGI-S, PGI-C), and clinician global impressions of severity and change in patients' daytime symptoms (CGI-S, CGI-C). Meaningful within-patient change estimates were 'triangulated' to identify a value where they converged.

RESULTS

In the open-label trial (N = 114), subjects with a 1-point or 1-step improvement on the anchors had mean increases in sTST of 60.1-83.2 min at day 8 and 55.5-68.2 min at day 15. For subjects with a 2-point or 2-step improvement on the anchors, mean increases in sTST were 79.6-81.4 min at day 8 and 80.1-93.5 min at day 15. In the phase III trial (N = 930), weekly average increases in sTST for subjects with a 1-point or 1-step improvement on the anchors were 39.3-46.7 min at month 1 and 47.3-58.3 min at month 3. For subjects with a 2-point or 2-step improvement on the anchors, mean increases in sTST were 60.7-76.2 min at month 1 and 70.1-87.7 min at month 3. Triangulation of these values supported a meaningful within-patient change threshold starting at 55 min.

CONCLUSION

Increasing sTST is an important treatment outcome for people with insomnia. An increase in sleep time of approximately 55 min is meaningful to patients.

CLINICAL TRIALS REGISTRATION

NCT03056053 (17 February 2017) and NCT03545191 (4 June 2018).

Comparison of Cardiovascular Health Profiles Across Population Surveys From 5 High- to Low-Income Countries

Background

To facilitate the shift from risk-factor management to primordial prevention of cardiovascular disease, the American Heart Association developed guidelines to score and track cardiovascular health (CVH). How the prevalence and trajectories of a high level of CVH across the life course compare among high- and lower-income countries is unknown.

Methods

Nationally representative survey data with CVH variables (physical activity, cigarette smoking, body mass index, blood pressure, blood glucose, and total cholesterol levels) were identified in Ethiopia, Bangladesh, Brazil, England, and the US for adults (aged 18-69 years and not pregnant). Data were harmonized, and CVH metrics were scored using the American Heart Association guidelines, as high (2), moderate (1), or low (0), with the prevalence of high scores (better CVH) across the life course compared across countries.

Results

Among 28,092 adults (Ethiopia n = 7686, 55.2% male; Bangladesh n = 6731, 48.4% male; Brazil n = 7241, 47.9% male; England n = 2691, 49.5% male, and the US n = 3743, 50.3% male), the prevalence of high CVH scores decreased as country income level increased. Declining CVH with age was universal across countries, but differences were already observable in those aged 18 years. Excess body weight appeared to be the main driver of poor CVH in higher-income countries, and the prevalence of current smoking was highest in Bangladesh.

Conclusions

Our findings suggest that CVH decline with age may be universal. Interventions to promote and preserve CVH throughout the life course are needed in all populations, tailored to country-specific time courses of the decline. In countries where the level of CVH remains relatively high, protection of whole societies from risk-factor epidemics may still be feasible.

Unraveling the directional relationship of sleep and migraine-like pain

Migraine and sleep disorders are common co-morbidities. Patients frequently link their sleep to migraine attacks suggesting a potential causal relationship between these conditions. However, whether migraine pain promotes or disrupts sleep or whether sleep disruption can increase the risk of migraine remains unknown. We assessed the potential impact of periorbital allodynia, a measure consistent with migraine-like pain, from multiple preclinical models on sleep quantity and quality. Additionally, we evaluated the possible consequences of sleep deprivation in promoting susceptibility to migraine-like pain. Following the implantation of electroencephalogram/electromyography electrodes to record sleep, mice were treated with either single or repeated systemic injections of nitroglycerin at the onset of their active phase (i.e. nocturnal awake period). Neither single nor repeated nitroglycerin affected the total sleep time, non-rapid eye movement sleep, rapid eye movement sleep, sleep depth or other measures of sleep architecture. To account for the possible disruptive effects of the surgical implantation of electroencephalogram/electromyography electrodes, we used immobility recordings as a non-invasive method for assessing sleep-wake behaviour. Neither single nor repeated nitroglycerin administration during either the mouse sleep (i.e. daylight) or active (i.e. night) periods influenced immobility-defined sleep time. Administration of an inflammatory mediator mixture onto the dura mater at either sleep or active phases also did not affect immobility-defined sleep time. Additionally, inhalational umbellulone-induced migraine-like pain in restraint-stressed primed mice did not alter immobility-defined sleep time. The possible influence of sleep disruption on susceptibility to migraine-like pain was evaluated by depriving female mice of sleep over 6 h with novel objects, a method that does not increase circulating stress hormones. Migraine-like pain was not observed following acute sleep deprivation. However, in sleep-deprived mice, subthreshold doses of systemic nitroglycerin or dural calcitonin gene-related peptide induced periorbital cutaneous allodynia consistent with migraine-like pain. Our data reveal that while migraine-like pain does not significantly disrupt sleep, sleep disruption increases vulnerability to migraine-like pain suggesting that a therapeutic strategy focused on improving sleep may diminish migraine attacks.

Neighborhood determinants of sleep and the moderating role of cultural factors among native adolescents

OBJECTIVE

This study examined the association between neighborhood social environment and sleep among urban American Indian and Alaska Native (AI/AN) adolescents as well as the moderating role of cultural factors in this association.

METHOD

The analytic sample included 133 urban AI/AN adolescents (age 12-16, 57.1% female, Mage = 14.03, SDage = 1.35). Perceived neighborhood social environment included safety and cohesion. Cultural factors included AI/AN cultural identification and historical loss. Sleep duration, efficiency, and wake after sleep onset (WASO) were measured via actigraphy. Sleep disturbance was measured via a questionnaire.

RESULTS

Greater neighborhood safety was significantly associated with lower sleep disturbance (b = -2.17, SE = 0.8, p = .008), higher sleep efficiency (b = 1.75, SE = 0.64, p = .006), and lower WASO (b = -8.60, SE = 3.34, p = .01). Neighborhood cohesion was not associated with any sleep outcomes. Cultural factors moderated the association between neighborhood social environment and sleep outcomes (p < .05). Specifically, both neighborhood safety and cohesion were associated with lower sleep disturbance, only among individuals reporting higher levels of AI/AN cultural identification. Further, neighborhood safety was associated with greater sleep efficiency and lower WASO (i.e., better sleep) only among adolescents with higher contemplation of historical loss.

CONCLUSIONS

Findings highlight the importance of considering cultural factors in addressing sleep and health disparities. AI/AN cultural identification and a sense of historical loss may be important targets for identifying adolescents who might benefit the most from policies and interventions focused on improving the social environment in order to improve sleep and other health outcomes. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Genome-wide association studies and polygenic risk score phenome-wide association studies across complex phenotypes in the human phenotype project

BACKGROUND

Genome-wide association studies (GWASs) associate phenotypes and genetic variants across a study cohort. GWASs require large-scale cohorts with both phenotype and genetic sequencing data, limiting studied phenotypes. The Human Phenotype Project is a longitudinal study that has measured a wide range of clinical and biomolecular features from a self-assignment cohort over 5 years. The phenotypes collected are quantitative traits, providing higher-resolution insights into the genetics of complex phenotypes.

METHODS

We present the results of GWASs and polygenic risk score phenome-wide association studies with 729 clinical phenotypes and 4,043 molecular features from the Human Phenotype Project. This includes clinical traits that have not been previously associated with genetics, including measures from continuous sleep monitoring, continuous glucose monitoring, liver ultrasound, hormonal status, and fundus imaging.

FINDINGS

In GWAS of 8,706 individuals, we found significant associations between 169 clinical traits and 1,184 single-nucleotide polymorphisms. We found genes associated with both glycemic control and mental disorders, and we quantify the strength of genetic signals in serum metabolites. In polygenic risk score phenome-wide association studies for clinical traits, we found 16,047 significant associations.

CONCLUSIONS

The entire set of findings, which we disseminate publicly, provides newfound resolution into the genetic architecture of complex human phenotypes.

FUNDING

E.S. is supported by the Minerva foundation with funding from the Federal German Ministry for Education and Research and by the European Research Council and the Israel Science Foundation.

Impact of sleep disruption on cognitive function in patients with postacute sequelae of SARS-CoV-2 infection: initial findings from a Neuro-COVID-19 clinic

Introduction

Fatigue, brain fog, and sleep disturbance are among the most common symptoms of postacute sequelae of SARS-CoV-2 infection (PASC). We sought to determine the impact of sleep disruption on cognition and quality of life in patients with neurologic manifestations of PASC (Neuro-PASC).

Methods

Thirty-nine patients were recruited from Neuro-COVID-19 clinic. Mean age was 48.1 years, 71.8% were female, and 82% were never hospitalized for COVID-19. Patients were evaluated via clinical assessment, quality-of-life measures in domains of cognitive function, fatigue, sleep disturbance, anxiety, and depression, NIH Toolbox cognitive tests, and 7 days of wrist actigraphy.

Results

The median number of neurologic symptoms attributed to PASC was 6, with brain fog being the most common in 89.7%. Regarding non-neurologic symptoms, 94.9% complained of fatigue and 74.4% of insomnia. Patients reported significant impairment in all quality-of-life domains and performed worse in a task of attention compared to a normative US population. Actigraphy showed Neuro-PASC patients had lower sleep efficiency, longer sleep latency (both p < 0.001), and later sleep midpoint (p = 0.039) compared to 71 age-matched healthy controls with no PASC history. Self-reported cognitive symptoms correlated with the severity of fatigue (p < 0.001), anxiety (p = 0.05), and depression (p < 0.01). Objective evidence of sleep disruption measured by wakefulness after sleep onset, sleep efficiency, and latency were associated with decreased performance in attention and processing speed.

Conclusion

Prospective studies including larger populations of patients are needed to fully determine the interplay of sleep disruption on the cognitive function and quality of life of patients with PASC.

Daily variation in sleepiness among firefighters while working the 24/48 and 48/96 shift schedules

Objective

To assess the daily relationship between prior-night total sleep time (TST) and next-day, afternoon sleep propensity among firefighters operating from two popular fire department shift schedules.

Methods

Dataset included 22 firefighters (24/48 shift schedule) and 20 firefighters (48/96 shift schedule). Daily TST was assessed using actigraphy and daily sleep propensity was assessed using the Epworth Sleepiness Scale (ESS), completed every afternoon.

Results

Separate one-way repeated measures ANOVA indicated statistically significant differences among daily sleep propensity within each shift schedule. Separate Pearson product moment correlations indicated moderate relationships between prior-night TST and next-day, afternoon sleep propensity.

Conclusion

When firefighters slept less, sleep propensity the following day increased. Least TSTs occurred on nights prior to commuting suggesting firefighters likely begin shifts without sufficient sleep and drive home without sufficient sleep, then experience greatest sleep propensity.

iSleepFirst: burnout, fatigue, and wearable-tracked sleep deprivation among residents staffing the medical intensive care unit

PURPOSE

This study aimed to evaluate the relationship between sleep, burnout, and psychomotor vigilance in residents working in the medical intensive care unit (ICU).

METHODS

A prospective cohort study of residents was implemented during a consecutive 4-week. Residents were recruited to wear a sleep tracker for 2 weeks before and 2 weeks during their medical ICU rotation. Data collected included wearable-tracked sleep minutes, Oldenburg burnout inventory (OBI) score, Epworth sleepiness scale (ESS), psychomotor vigilance testing, and American Academy of Sleep Medicine sleep diary. The primary outcome was sleep duration tracked by the wearable. The secondary outcomes were burnout, psychomotor vigilance (PVT), and perceived sleepiness.

RESULTS

A total of 40 residents completed the study. The age range was 26-34 years with 19 males. Total sleep minutes measured by the wearable decreased from 402 min (95% CI: 377-427) before ICU to 389 (95% CI: 360-418) during ICU (p < 0.05). Residents overestimated sleep, logging 464 min (95% CI: 452-476) before and 442 (95% CI: 430-454) during ICU. ESS scores increased from 5.93 (95% CI: 4.89, 7.07) to 8.33 (95% CI: 7.09,9.58) during ICU (p < 0.001). OBI scores increased from 34.5 (95% CI: 32.9-36.2) to 42.8 (95% CI: 40.7-45.0) (p < 0.001). PVT scores worsened with increased reaction time while on ICU rotation (348.5 ms pre-ICU, 370.9 ms post-ICU, p < 0.001).

CONCLUSIONS

Resident ICU rotations are associated with decreased objective sleep and self-reported sleep. Residents overestimate sleep duration. Burnout and sleepiness increase and associated PVT scores worsen while working in the ICU. Institutions should ensure resident sleep and wellness checks during ICU rotation.

Assessing 'readiness' by tracking fluctuations in daily sleep duration and their effects on daily mood, motivation, and sleepiness

STUDY OBJECTIVES

Consumer sleep trackers issue daily guidance on 'readiness' without clear empirical basis. We investigated how self-rated mood, motivation, and sleepiness (MMS) levels are affected by daily fluctuations in sleep duration, timing, and efficiency and overall sleep regularity. We also determined how temporally specific these associations are.

METHODS

119 healthy university students (64 female, mean age = 22.54 ± 1.74 years) wore a wearable sleep tracker and undertook twice-daily smartphone-delivered ecological momentary assessment of mood, motivation, and sleepiness at post-wake and pre-bedtime timings for 2-6 weeks. Naps and their duration were reported daily. Nocturnal sleep on 2471 nights were examined using multilevel models to uncover within-subject and between-subject associations between sleep duration, timing, efficiency, and nap duration on following day MMS ratings. Time-lagged analyses examined the temporal specificity of these associations. Linear regression models investigated associations between MMS ratings and sleep variability, controlling for sleep duration.

RESULTS

Nocturnal sleep durations were short (6.03 ± 0.71 h), and bedtimes were late (1:42AM ± 1:05). Within-subjects, nocturnal sleep longer than a person's average was associated with better mood, higher motivation, and lower sleepiness after waking. Effects of such longer sleep duration lingered for mood and sleepiness till the pre-bedtime window (all Ps < .005) but did not extend to the next day. Between-subjects, higher intraindividual sleep variability, but not sleep duration, was associated with poorer mood and lower motivation after waking. Longer average sleep duration was associated with less sleepiness after waking and lower motivation pre-bedtime (all Ps < .05). Longer naps reduced post-nap sleepiness and improved mood. Controlling for nocturnal sleep duration, longer naps also associated with lower post-waking sleepiness on the following day.

CONCLUSIONS

Positive connections between nocturnal sleep and nap duration with MMS are temporally circumscribed, lending credence to the construction of sleep-based, daily 'readiness' scores. Higher sleep duration variability lowers an individual's post waking mood and motivation.

CLINICAL TRIAL ID

ClinicalTrials.gov NCT04880629.

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.

Sex differences in endocannabinoid tone in a pilot study of cannabis use disorder and acute cannabis abstinence

Cannabis use disorder (CUD) presents differently in men and women, particularly in symptoms of cannabis withdrawal. Novel pharmacotherapeutic interventions for CUD, such as those that target the endocannabinoid (eCB) system, must be developed in a manner consistent with these sex differences. The present pilot study sought to prospectively assess sex differences in cannabis withdrawal in a small sample of adults with moderate-to-severe CUD and to determine if withdrawal was associated with peripheral eCB and eCB congener tone. Men and women (n = 5/sex) completed 2 weeks of study participation separated by 1 month; in the latter week, participants abstained from cannabis use. Each week, participants attended in-person laboratory visits during which blood was drawn repeatedly to assess plasma eCB and eCB congener tone. Participants also completed multiple daily ambulatory assessments to assess cannabis use and withdrawal symptoms. As anticipated, women reported a greater increase in withdrawal symptoms during the abstinent week [Δ = 9.4 (SE = 1.1); p < 0.001] than men [Δ = 1.2 (SE = 1.2); p = 0.35]. Sex differences in levels of the eCB N-arachidonoylethanolamide (AEA), as well as the eCB congeners stearoylethanolamide (SEA) and linoleylethanolamide (LEA), were evident during abstinence at the morning time point only (p's < 0.05). LEA was associated with withdrawal symptom expression in both sexes [β = 0.16 (SE = 0.09)] and palmitoylethanolamide (PEA) [β = 0.22 (SE = 0.13)] and 2-arachidonoylglycerol (2-AG) [β = 0.32 (SE = 0.15)] were associated with withdrawal symptoms in women only. Pharmacotherapeutic development for CUD should consider evident sex differences in eCB and eCB congener tone during abstinence and their associations with cannabis withdrawal, as eCB-based interventions may produce differential effects by sex.

Subjective versus objective sleep in men with Klinefelter syndrome

OBJECTIVES

To investigate sleep among men with Klinefelter syndrome (KS).

METHOD

We compared the sleep domains latency, disturbance, and efficiency in 30 men with KS (M age = 36.7 years, SD = 10.6) to 21 age-matched non-KS controls (M age = 36.8 years, SD = 14.4). Actigraphs were used to objectively measure sleep across 7 days and nights. Participants also completed a sleep diary over the same period, and the Pittsburgh Sleep Quality Index (PSQI).

RESULTS

The mean correlation between the objective and subjective sleep measures was lower for the KS sample (M r = .15) than for controls (M r = .34). Sleep disturbance was significantly larger in the KS sample, as measured by actigraphy (p = .022, d = 0.71) and the PSQI (p = .037, d = 0.61). In regression models predicting sleep domains from KS status, age, educational level, vocational status, IQ, and mental health, KS status was not a significant predictor. Higher age was associated with more actigraphy-measured sleep disturbance. Higher educational level and being employed were associated with better sleep efficiency.

CONCLUSIONS

Sleep disturbance may be a particular problem for men with KS and should be measured with complimentary methods.

The association between nutritional status and sleep quality of Chinese community-dwelling older adults

BACKGROUND

Sleep disorders are a common syndrome and could affect the life quality of the older adults.

AIMS

This study aimed to investigate the association between nutritional status and sleep quality in the Chinese community-dwelling older adults.

METHODS

A total of 2,878 participants ≥ 65 years old from the Yiwu Elderly Cohort were included in the study. Nutritional status was assessed using the Mini Nutritional Assessment Short Form (MNA-SF). Participants were categorized as subjects with malnutrition, at risk of malnutrition or well-nourished based on their MNA-SF score. Pittsburgh Sleep Quality Index (PSQI) was used to identify sleep disorders. PSQI score ≥ 6 was categorized as poor sleep quality.

RESULTS

Among the 2,878 participants (mean age 72.71 ± 5.79 years, 50.3% men), 31.5% (n = 906) were classified as having sleep disorders, and 25.5% were identified as malnutrition or at risk of malnutrition. We found a significantly relationship between nutritional status and sleep quality in older adults, and the results showed well-nourished decreased the risk of sleep disorders (OR = 0.32, 95% CI = 0.13, 0.75). And well-nourished status was significantly associated with less daytime dysfunction, adequate sleep duration, and good subjective sleep quality (all P < 0.05).

CONCLUSION

There was a close association of nutritional status and sleep quality in older adults. We should pay more attention to the nutritional status of older people with sleep problems, as well as the sleep quality of older adults with malnutrition.

Associations between Birth Weight and Adult Sleep Characteristics: A Cross-Sectional Analysis from the UAEHFS

Abnormal birth weight, particularly low birth weight (LBW), is known to have long-term adverse health consequences in adulthood, with disrupted sleep being suggested as a mediator or modifier of this link. We thus aimed to assess the associations between birth weight and self-reported adult sleep characteristics: sleep duration, difficulty waking up in the morning, daily nap frequency, sleep problems at night, snoring, daytime tiredness or sleepiness, and ever-stop breathing during sleep. This cross-sectional analysis used the United Arab Emirates Healthy Future Study data collected from February 2016 to March 2023 involving 2124 Emiratis aged 18-61 years. We performed a Poisson regression under unadjusted and age-sex-and-BMI-adjusted models to obtain the risk ratio and its 95% confidence interval for our analysis of the association between birth weight and each adult sleep characteristics, compared to individuals with normal birth weight (≥2.5 kg). Those with LBW had significantly a 17% increased risk of difficulty waking up in the morning, compared to those with normal birth weight. In addition, females with LBW history were also at an increased risk of reporting difficulty waking up in the morning. Studies with objective sleep assessments that include measurements of more confounding factors are recommended to confirm these risks.

Comparison of cardiovascular health profiles across population surveys from five high- to low-income countries

Aims

With the greatest burden of cardiovascular disease morbidity and mortality increasingly observed in lower-income countries least prepared for this epidemic, focus is widening from risk factor management alone to primordial prevention to maintain high levels of cardiovascular health (CVH) across the life course. To facilitate this, the American Heart Association (AHA) developed CVH scoring guidelines to evaluate and track CVH. We aimed to compare the prevalence and trajectories of high CVH across the life course using nationally representative adult CVH data from five diverse high- to low-income countries.

Methods

Surveys with CVH variables (physical activity, cigarette smoking, body mass, blood pressure, blood glucose, and total cholesterol levels) were identified in Ethiopia, Bangladesh, Brazil, England, and the United States (US). Participants were included if they were 18-69y, not pregnant, and had data for these CVH metrics. Comparable data were harmonized and each of the CVH metrics was scored using AHA guidelines as high (2), moderate (1), or low (0) to create total CVH scores with higher scores representing better CVH. High CVH prevalence by age was compared creating country CVH trajectories.

Results

The analysis included 28,092 adults (Ethiopia n=7686, 55.2% male; Bangladesh n=6731, 48.4% male; Brazil n=7241, 47.9 % male; England n=2691, 49.5% male, and the US n=3743, 50.3% male). As country income level increased, prevalence of high CVH decreased (>90% in Ethiopia, >68% in Bangladesh and under 65% in the remaining countries). This pattern remained using either five or all six CVH metrics and following exclusion of underweight participants. While a decline in CVH with age was observed for all countries, higher income countries showed lower prevalence of high CVH already by age 18y. Excess body weight appeared the main driver of poor CVH in higher income countries, while current smoking was highest in Bangladesh.

Conclusion

Harmonization of nationally representative survey data on CVH trajectories with age in 5 highly diverse countries supports our hypothesis that CVH decline with age may be universal. Interventions to promote and preserve high CVH throughout the life course are needed in all populations, tailored to country-specific time courses of the decline. In countries where CVH remains relatively high, protection of whole societies from risk factor epidemics may still be feasible.

Does workplace telepressure get under the skin? Protocol for an ambulatory assessment study on wellbeing and health-related physiological, experiential, and behavioral concomitants of workplace telepressure

BACKGROUND

The daily working life of many employees requires the use of modern information and communication technology (ICT) devices such as computers, tablets, and smartphones. The double-edged nature of digital work environments has been increasingly highlighted. Benefits such as increased flexibility come at a personal cost. One of the potential downsides is workplace telepressure, i.e., the experience of urge and preoccupation to quickly reply to work-related messages and demands using ICT. There is initial - mainly survey-based-evidence that workplace telepressure may have negative effects on a variety of wellbeing and health outcomes.

AIMS AND HYPOTHESES

Adopting the Effort-Recovery Model and the concept of allostatic load as theoretical frameworks, the present study aims to investigate the hypothesis that workplace telepressure is significantly associated with increased "wear and tear", in the form of more psychosomatic complaints, worse sleep quality (self-reported and actigraphy-based), worse mood, and biological alterations (lower cardiac vagal tone, lower anabolic balance defined as the ratio of salivary dehydroepiandrosterone to salivary cortisol, and higher salivary alpha-amylase). Additionally, the study aims to investigate the hypothesis that connection to work defined as work-related workload and work-related perseverative cognition plays a significant role in the mediation of these relationships.

METHODS

To test our hypotheses, we will conduct an ambulatory assessment study with a convenience sample of 120 healthy workers regularly using ICTs for job communication. For one week, participants will be asked to complete electronic diaries assessing their level of workplace telepressure, psychosomatic complaints, sleep quality, mood, work-related workload, and work-related perseverative cognition. They will also continuously wear the Bittium Faros 180L ECG monitor, the wrist-worn actigraph MotionWatch 8, and perform saliva sampling five times per day.

DISCUSSION

This study will be the most comprehensive ambulatory investigation of workplace telepressure and its psychophysiological concomitants to date and constitutes an important step towards understanding how high levels of workplace telepressure may lead in the long term to secondary alterations (e.g., hypertension, chronic inflammation) and disease (e.g., heart disease). The findings of this study are also anticipated to contribute to guiding the development and implementation of interventions, programs, and policies relevant to employees' digital wellbeing.

How many hours do you sleep? A comparison of subjective and objective sleep duration measures in a sample of insomnia patients and good sleepers

Our objective was to assess the agreement and linear relationships amongst multiple measures of sleep duration in a sample of patients with insomnia disorder and good sleeper controls. We retrospectively analysed data from 123 patients with insomnia disorder and 123 age- and gender-matched good sleeper controls who completed a simple subjective habitual sleep duration question (Pittsburgh Sleep Quality Index), a sleep diary (5-14 days), 2 nights of polysomnography, and two corresponding morning subjective estimates of sleep duration. Descriptive statistics, linear regression analyses and Bland-Altman plots were used to describe the relationship and (dis)agreement between sleep duration measures. Relationships between polysomnography and the simple question as well as between polysomnography and sleep diary were weak to non-existent. Subjective measures and polysomnography did not agree. Sleep duration measured with the Pittsburgh Sleep Quality Index or sleep diary was about 2 hr above or up to 4 hr below polysomnography-measured sleep duration. Patients with insomnia disorder, on average, reported shorter sleep duration compared with polysomnography, while good sleeper controls, on average, reported longer sleep duration compared with polysomnography. The results suggest that subjective and objective measures apparently capture different aspects of sleep, even when nominally addressing the same value (sleep duration). They disagree in both patients with insomnia disorder and good sleeper controls, but in different directions. Studies assessing sleep duration should take into account both the investigated population and the assessment method when interpreting results. Future studies should continue to investigate possible psychological and physiological correlates of sleep (mis)perception.

Is daytime napping an effective strategy to improve sport-related cognitive and physical performance and reduce fatigue? A systematic review and meta-analysis of randomised controlled trials

OBJECTIVE

To estimate the association between daytime napping and cognitive and physical sport performance and fatigue after normal sleep and partial sleep deprivation (less sleep duration than necessary).

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

The PubMed, Scopus, Web of Science, Cochrane Central, SportDiscus and PsycINFO databases.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Randomised controlled trials on the effect of daytime napping on sport performance and fatigue available from inception to 2 December 2022. Standardised mean differences (SMD) and their 95% compatibility intervals (CI) were estimated with the DerSimonian-Laird method through random effect models.

RESULTS

In the 22 included trials, 291 male participants (164 trained athletes and 127 physically active adults) aged between 18 and 35 years were studied. When performed after a normal night of sleep, napping from 12:30 hours to 16:50 hours (with 14:00 hours being the most frequent time) improved cognitive (SMD=0.69, 95% CI: 0.37 to 1.00; I²=71.5%) and physical performance (SMD=0.99, 95% CI: 0.67 to 1.31; I²=89.1%) and reduced the perception of fatigue (SMD=-0.76, 95% CI: -1.24 to -0.28; I²=89.5%). The positive effects of napping were also confirmed after partial sleep deprivation. Overall, the benefits were higher with a nap duration between 30 and <60 min and when the time from nap awakening to test was greater than 1 hour.

CONCLUSIONS

After a night of normal sleep or partial sleep deprivation, a daytime nap between 30 and <60 min has a moderate-to-high effect on the improvement of cognitive performance and physical performance and on the reduction of perceived fatigue.

PROSPERO REGISTRATION NUMBER

CRD42020212272.

Trends in sleep duration in Korea: The Korean time use survey

OBJECTIVES

An accurate assessment of sleep duration is important in that it can be one of the indicators of a country's overall health and well-being. The global trend in sleep duration is controversial according to study types. We investigated trends in sleep duration in South Korea with a time diary method.

METHODS

Data from the Korean Time Use Survey (KTUS) in 2004, 2009, 2014, and 2019, were analyzed. The KTUS is a nationwide, cross-sectional survey that measures daily time use patterns of individuals and has been performed every five years by Statistics Korea. For this survey, all participants were asked to record their activities for 2 continuous days in 10-min intervals.

RESULTS

Among the 168,682 people who completed the survey in 2004 through 2019, the final analytical sample consisted of 91,998 individuals. Over 15 years, the sleep duration of the Korean population increased from 411.1 min (SD 22.5) in 2004 to 434.5 min (SD 26.1) in 2019 (p for trend <0.001). This increase was observed for all age groups. Over the study period, while bedtime showed no significant change, wake time was generally delayed for all age groups. The increase in sleep duration in the Korean population was largely due to catch-up sleep on Saturdays, which was substantially prolonged with belated wake times.

CONCLUSION

Our nationwide time use survey data showed that sleep duration in South Korea has increased over the past 15 years but still has room for improvement in terms of weekday sleep duration.

Lingering impacts on sleep following the Daylight Savings Time transition in the Project Baseline Health Study

Background

The “spring forward” change to Daylight Savings Time (DST) has been epidemiologically linked with numerous health and safety risks in the days following the transition, but direct measures of sleep are infrequently collected in free-living individuals.

Methods

The Project Baseline Health Study (PBHS), a prospective, multicenter, longitudinal representative U.S. cohort study that began in 2017 launched a Sleep Mission in March 2021 to characterize sleep using patient-reported and wearable device measures, in free-living circumstances during the DST switch. Estimated sleep period duration, subjective restedness, and sleep quality were compared before and after the DST transition during specified timeframes.

Results

Of the total PBHS population of 2502 participants, 912 participants received an invitation and 607 responded by March 6th. Among those, 420 participants opted into the Sleep Mission (69.2%). The transition to DST resulted in both acute and lingering impacts on sleep. Acute effects included a 29.6 min reduction in sleep period (p = 0.03), increases in the proportion of patients who reported ‘sleeping poorly’ (from 1.7 to 13.6% [p < 0.01]), and with scores falling into the ‘unrested’ category (from 1.7 to 8.5% [p = 0.046]). There was also a downward trend in the proportion of participants reporting being rested in the morning following the DST transition (from 62.7% on March 7 to 49.2% on March 14 [p = 0.10]). Lingering effects included a 18.7% relative decrease in the daily likelihood of participants reporting restedness (from 49.2% in the week prior to the DST transition to 40.0% in the week after [p < 0.01]).

Conclusion

The DST transition is associated with an acute reduction in sleep period, as well as an increased proportion of individuals reporting poor sleep and unrestedness. The DST transition also resulted in lingering impacts on self-reported restedness, lasting into the week following the transition. This work adds to a growing understanding of the persistence of impacts on sleep health metrics due to the DST transition.

Sleep Latency and Post-Traumatic Stress Disorder Among Retired Career Florida Firefighters: Evidence From the Advancing Epidemiology of Retired Firefighters Aging Longitudinally Cohort

OBJECTIVE

Our objective was to estimate the association of post-traumatic stress disorder (PTSD) and sleep latency among retired firefighters.

METHODS

Baseline health survey data collected from retried career Florida firefighters participating in an ongoing prospective cohort study from 2017 to 2021 were analyzed. Risk for PTSD was assessed using a four-item primary care PTSD screening construct, and sleep onset latency was assessed by self-reported length of time to fall asleep.

RESULTS

Among the 500 participants, 8.0% screened positive for PTSD risk and 37.6% had prolonged sleep onset latency (≥20 minutes to fall asleep). Retired firefighters with PTSD risk were 2.7 times more likely (adjusted odds ratio, 2.70; 95% confidence interval, 1.27-5.75) to have prolonged sleep latency compared with those without PTSD risk while controlling for covariates.

CONCLUSIONS

Retired firefighters who screen positive for PTSD risk are three times more likely to report delayed sleep onset latency.

Do the relationships of physical activity and total sleep time with cognitive function vary by age and biological sex? A cross-sectional analysis of the Canadian Longitudinal Study on Aging

OBJECTIVES

Physical activity (PA) and total sleep time (TST) are each associated with cognition; however, whether these relationships vary by age and biological sex is unclear. We examined the relationships of PA or TST with cognition, and whether age and sex moderated these relationships, using baseline data from the Canadian Longitudinal Study on Aging (CLSA; 2010-2015).

STUDY DESIGN

A cross-sectional analysis of participants from the Comprehensive cohort of the CLSA with complete PA and sleep data (n = 20,307; age range 45-86 years).

MAIN OUTCOME MEASURES

PA and TST were measured using the Physical Activity Scale for the Elderly (PASE) and self-reported TST over the past month. Cognition was indexed using a three-factor structural equation model (i.e., memory, executive function, and verbal fluency).

RESULTS

Non-linear restricted cubic spline models indicated that PA and TST explained statistically significant (p < 0.01) but modest variance of each cognitive domain (<1 % of 23-24 % variance). Age and sex did not moderate associations of PA with any cognitive domain. However, age and sex moderated relationships of TST with cognition, whereby: 1) associations of TST with memory decreased with age for males and females; and 2) males and females had different age-associated relationships of TST with executive function and verbal fluency.

CONCLUSIONS

PA and TST modestly contribute to multiple domains of cognition across middle and older adulthood. Importantly, the association of PA with cognition does not appear to vary across middle or older adulthood, nor does it vary by biological sex; however, TST appears to have a complex relationship with multiple domains of cognition which is both age- and sex-dependent.

Adolescent sleep quality and quantity and educational attainment: a test of multiple mechanisms using sibling difference models

OBJECTIVE

The objective of this study is to determine whether and how sleep quality and quantity during adolescence are related to educational attainment in adulthood. This study also investigates whether this relationship varies by gender.

METHODS

Using data from the National Longitudinal Study of Adolescent to Adult Health, the present study employed a sibling fixed effect approach that takes into account unobserved family background factors such as genetics and social environments. Gender-stratified analyses were conducted to consider the potential gendered relationship between adolescent sleep and educational attainment.

RESULTS

Controlling for unobserved family-level heterogeneity attenuated the associations between adolescent sleep characteristics and educational attainment, albeit in different ways for boys and girls. Gender-stratified models suggest that, for boys, only the association between short sleep duration and educational attainment was robust to adjustment for sibling fixed effects. In contrast, for girls, among three sleep quality measures, only trouble falling or staying asleep remained significantly associated with educational attainment even after controlling for unobserved family heterogeneity. Sibling fixed effects estimates suggest that short sleep duration (6 or fewer hours per night) was negatively associated with years of schooling only among boys (b = -0.443), whereas trouble falling or staying asleep was associated with a reduction in years of schooling only among girls (b = -0.556). The mechanisms underlying the observed associations also differed by gender. For boys, the association between short sleep duration and educational attainment was partially explained by a combination of educational, social, and psychological factors. Only intermediate educational factors explained part of the association between trouble falling or staying asleep and educational attachment among girls.

CONCLUSIONS

The study's finding that the relationship between adolescent sleep characteristics and educational attainment and the mechanisms underlying this relationship differ by gender calls attention to the need for gender-specific interventions.

Prevalence of insomnia and poor sleep quality in the prison population: A systematic review

Insomnia is a public health concern with several associated negative health-related outcomes. Risk factors for insomnia place the prison population at an increased risk of inadequate sleep. This paper systematically reviewed the literature reporting on the prevalence of insomnia and poor sleep quality in the prison population. Following a comprehensive database search and screening process, 12 studies were eligible for inclusion in this review. Six studies provided prevalence rates for insomnia and nine for poor sleep quality. Varied prevalence rates were found for insomnia (i.e. 26.2%-72.5%) and poor sleep quality (i.e. 42.8%-88.2%). Evaluation of the prevalence rates revealed varied measurement of sleep quality, inconsistent parameters of standardised measures, and methodological heterogeneity. Other considerations were given to geographical differences, the use of self-report data, gender difference, environmental factors and comorbidities of insomnia. The review highlighted an increase in the quantity of studies and some improved quality; although the findings were highly variable, in the main, inadequate sleep amongst prisoners was higher than the general population. Limitations of the review and implications for further research are discussed.

Both Short and Long Sleep Durations Are Associated with Poor Cognition and Memory in Chinese Adults Aged 55+ Years-Results from China Health and Nutrition Survey

We aimed to examine the associations between sleep duration and cognitive functions and memory in older Chinese adults attending the China Health and Nutrition Survey. A total of 7924 participants 55 years and older who reported their sleep duration and had a cognitive screen test in 2004, 2006, and 2015 were included in the analysis. Mixed-effects logistic regression models were used to assess the associations. A short sleep duration (≤6 h/day) and long sleep duration (≥10 h/day) were positively associated with a low global cognitive score (odds ratio-OR: 1.23, 95% CI: 1.01-1.50; OR: 1.47, 95% CI: 1.17-1.79, respectively). Both short sleepers and long sleepers had an increased risk of self-reported poor memory (OR: 1.63, 95% CI: 1.39-1.91; OR: 1.48, 95% CI: 1.25-1.74, respectively). No differences in the above associations were found for income, education, and urbanity. In conclusion, both the short and long sleep duration were associated with declined cognition and memory. Maintaining a normal sleep duration may aid in the prevention of cognitive function decline in older adults.

Recreational cannabis use is associated with poorer sleep outcomes in young adult African Americans

INTRODUCTION

The present study sought to determine the relationship between self-reported cannabis use dosage in grams per day with (1) objective sleep outcomes: sleep efficiency (SE), sleep onset latency SOL and number of night-time awakenings (NWAK) (2) if objective and subjective sleep measures, using the PSQI, differed between cannabis users and non-cannabis users.

METHODS

Our sample included 178 participants, aged 18-35 years. We collected demographic information, cannabis use in dosage per day and frequency of use, depressive symptoms through the CESD, and subjective sleep reports using the PSQI. After the survey assessment, we monitored sleep using the Phillips Actiwatch Spectrum watch for a minimum of 5 nights.

RESULTS

The amount of cannabis consumed per day was inversely related to SOL and SE, and positively related to NWAK. After controlling for covariates, regression models were statistically significant for predicting SOL (β = -0.369, p <.001), SE (β = -0.232, p <.05) and NWAK, (β = -0.318, p <.001), indicating cannabis dosage per day is the strongest predictor for the sleep parameters. Subjective sleep measures did not differ from cannabis users versus non-cannabis users.

CONCLUSION

Recreational cannabis use is beneficial for SOL but may be detrimental to SE as those who reported increased cannabis use also had more NWAK. Cannabis may be useful for sleep onset, results suggest that increased use does not aid in sleep maintenance.

Validation of an automated sleep detection algorithm using data from multiple accelerometer brands

To evaluate the criterion validity of an automated sleep detection algorithm applied to data from three research-grade accelerometers worn on each wrist with concurrent laboratory-based polysomnography (PSG). A total of 30 healthy volunteers (mean [SD] age 31.5 [7.2] years, body mass index 25.5 [3.7] kg/m² ) wore an Axivity, GENEActiv and ActiGraph accelerometer on each wrist during a 1-night PSG assessment. Sleep estimates (sleep period time window [SPT-window], sleep duration, sleep onset and waking time, sleep efficiency, and wake after sleep onset [WASO]) were generated using the automated sleep detection algorithm within the open-source GGIR package. Agreement of sleep estimates from accelerometer data with PSG was determined using pairwise 95% equivalence tests (±10% equivalence zone), intraclass correlation coefficients (ICCs) with 95% confidence intervals and limits of agreement (LoA). Accelerometer-derived sleep estimates except for WASO were within the 10% equivalence zone of the PSG. Reliability between data from the accelerometers worn on either wrist and PSG was moderate for SPT-window duration (ICCs ≥ 0.65), sleep duration (ICCs ≥ 0.54), and sleep onset (ICCs ≥ 0.61), mostly good for waking time (ICCs ≥ 0.80), but poor for sleep efficiency (ICCs ≥ 0.08) and WASO (ICCs ≥ 0.08). The mean bias between all accelerometer-derived sleep estimates worn on either wrist and PSG were low; however, wide 95% LoA were observed for all sleep estimates, apart from waking time. The automated sleep detection algorithm applied to data from Axivity, GENEActiv and ActiGraph accelerometers, worn on either wrist, provides comparable measures to PSG for SPT-window and sleep duration, sleep onset and waking time, but a poor measure of wake during the sleep period.

Sleep dimensions are associated with obesity, poor diet quality and eating behaviors in school-aged children

Objectives

The aim of this cross-sectional study was to investigate the association between sleep dimensions (duration, patterns, and disturbances) with body mass index (BMI), diet quality, and eating behaviors in school-aged children. Additionally, we aimed to investigate whether obesogenic eating behaviors (higher food responsiveness, lower satiety responsiveness, and less slowness in eating) and poor diet quality could mediate the potential association between sleep and obesity in school-aged children.

Materials and methods

For all participants (n = 588 children, age 5–12 years; 51% girls) we evaluated: sleep dimensions, BMI, diet quality, eating behaviors (food responsiveness, satiety responsiveness and slowness in eating). Linear regression models were used to test associations between exposure and outcome variables. Additionally, path analysis was conducted to test whether eating behaviors mediated the relationship between sleep and obesity.

Results

Shorter sleep duration (β = −0.722, p = 0.009) and greater sleep disturbances (β = 0.031, p = 0.012) were significantly associated with BMI. Additionally, we observed that diet quality was significantly associated with sleep duration (β = 0.430, p = 0.004), the midpoint of sleep (β = −0.927, p < 0.001), and sleep disturbances (β = −0.029, p < 0.001). Among other findings, greater sleep disturbances were associated with food responsiveness (β = 0.017, p < 0.001), satiety responsiveness (β = 0.015, p < 0.001), and slowness in eating (β = 0.012, p < 0.001). Importantly, food responsiveness was found as significant mediator of the relationship between sleep and BMI (R = 0.427, R² = 0.182, p < 0.001).

Conclusions

Late sleep patterns, short sleep duration, and greater sleep disturbances are significantly related with what and how school-aged children eat. Importantly, poor diet quality was significantly related to all three sleep dimensions, while eating behaviors had a significant relationship with greater sleep disturbances. These findings may be relevant to the development of behavioral targets to prevent childhood obesity, including sleep hygiene guidelines as a strategy to improve children's eating habits, as well as their BMI.

Healthy lifestyle over the life course: Population trends and individual changes over 30 years of the Doetinchem Cohort Study

For five health-related lifestyle factors (physical activity, weight, smoking, sleep, and alcohol consumption) we describe both population trends and individual changes over a period of 30 years in the same adult population. Dichotomous indicators (healthy/unhealthy) of lifestyle were analyzed for 3,139 participants measured every 5 years in the Doetinchem Cohort Study (1987-2017). Population trends over 30 years in physical inactivity and "unhealthy" alcohol consumption were flat (i.e., stable); overweight and unhealthy sleep prevalence increased; smoking prevalence decreased. The proportion of the population being healthy on all five lifestyle factors declined from 17% in the round 1 to 10.8% in round 6. Underlying these trends a dynamic pattern of changes at the individual level was seen: sleep duration and physical activity level changed in almost half of the individuals; Body Mass Index (BMI) and alcohol consumption in one-third; smoking in one-fourth. Population trends don't give insight into change at the individual level. In order to be able to gauge the potential for change of health-related lifestyle, it is important to take changes at the individual level into account.

Examining the role of systemic chronic inflammation in diet and sleep relationship

BACKGROUND

It is well known that systemic chronic inflammation (SCI), which can be modulated by diet, is associated with poor sleep outcomes. However, the role of SCI in diet health and sleep quality relationship has not been well established.

METHODS

Here, by using the UK Biobank data set, we assessed the association between markers of SCI (leukocyte, platelet, lymphocyte, neutrophil, and basophil counts; C-reactive protein levels and neutrophil to lymphocyte ratio (NLR)), habitual intake of food groups, diet health and sleep quality in 449,084 participants. We also formally tested the possibility that SCI might mediate the relationship between diet health and sleep quality.

RESULTS

Our results revealed (i) negative associations between SCI and food groups that are abundant in healthy diets (fruit, vegetable and oily and non-oily fish) and (ii) positive associations between SCI and food groups that are abundant in unhealthy diets (processed meat). Sleep quality was also negatively associated with platelet counts, CRP levels and NLR. Crucially, however, while platelet and neutrophil counts, CRP levels and NLR fully mediated the association between diet health and sleep quality, leukocyte, lymphocyte and basophil counts partially mediated the associations between diet health and sleep quality.

CONCLUSION

Reducing SCI via dietary interventions could be an effective primary and/or complementary strategy to increase sleep quality. Further interventional trials are warranted to (i) establish the strength of associations, preferably by using validated diet and sleep measures and (ii) examine longer term effects of anti-inflammatory diets on sleep-, diet- and inflammation-related health outcomes.

Associations of α-linolenic acid dietary intake with very short sleep duration in adults

Objectives

This study aimed to investigate the association of α-linolenic acid (ALA; 18:3 ω-3) dietary intake with very short sleep duration (<5 h) in adults based on the CDC's National Health and Nutrition Examination Survey data.

Methods

Multinomial logistic regression was used to explore the association of ALA intake with very short sleep. To make the estimation more robust, bootstrap methods of 1,000 replications were performed. Rolling window method was used to investigate the trend of the odds ratios of very short sleep with age. A Kruskal-Wallis test was applied to estimate the differences in the ORs of very short sleep between genders and different age groups.

Results

Compared with the first tertile, the ORs of very short sleep and the corresponding 95% CIs for the second and the third tertile of dietary ALA intake in males were 0.618 (0.612, 0.624) and 0.544 (0.538, 0.551), respectively, and in females were 0.575 (0.612, 0.624) and 0.432 (0.427, 0.437). In most cases, the differences between different ages were more significant than those between different sexes. Men's very short sleep odds ratios for the second tertile of ALA intake increased linearly with age before 60.

Conclusions

The risk of a very short sleep duration was negatively related to the dietary intake of ALA. The effect of ALA on very short sleep is significantly different among groups of different genders and ages.

Effects of COVID-19 lockdown on sleep duration, sleep quality and burnout in faculty members of higher education in Mexico

This paper aims to assess the differences and associations of the effect of COVID-19 on sleep habits, sleep quality, and burnout symptoms among faculty members of higher education in Mexico. This was a cross-sectional study with a total sample of 214 faculty members of higher education from Mexico between May 18th and June 10th of 2020. We applied questionnaires containing sociodemographic and specific questions regarding sleep habits, sleep quality, and burnout symptoms. The results show that during COVID-19 faculty members delayed their bedtime and rise time. No change was found with weekdays time in bed, however, during weekends, time in bed was more than an hour shorter. Social jetlag decreased significantly during COVID-19. Furthermore, during COVID-19, those who reported low sleep quality were more likely to report higher symptoms of emotional exhaustion and those who slept less on weekends were more likely to report higher symptoms of depersonalization. These results suggest that the COVID-19 pandemic may have an effect on sleep and sleep quality and burnout symptoms of faculty members from higher education in Mexico.