"It's Just [Complicated] Sleep": Discourses of Sleep and Aging in the Media.

The media are influential in shaping beliefs and attitudes on aging and health-related behaviors. Sleep is increasingly recognized as a key pillar for healthy aging. However, the role of media representations of sleep is yet to be assessed with regard to discourses of aging. Texts from New Zealand's main free online news source were collated using key words "sleep" together with "aging," "older," "elderly," or "dementia" between 2018 and 2021. Contents of 38 articles were interpreted using critical discourse analysis. Discursive constructions described an inevitable decline of sleep with aging, including impacts of both physiological decline and life stage transitions; sleep's role as both a remedy and risk for ill health and disease; and the simplification of solutions for self-managing sleep juxtaposed alongside recognition of its complexity. The audience of these complex messages is left in the invidious position of both pursuing sleep practices to prevent age-related decline, whilst also being told that sleep degradation is inevitable. This research demonstrates the complexity of media messaging and the fraught options it offers: good sleep as both a reasonable achievement to strive for and as impossibly idealistic. Findings mirror two predominant health identities available to older people, as responsible for resisting aging or as falling into inevitable decline. This reveals additional expectations around appropriate time use and behaviors with aging. More nuanced messaging that goes beyond sleep as a resource for health and waking productivity is recommended. Acknowledging the complexity of sleep, aging, and society could be the starting point of such adaptation.

Sleep-in to stay well: addressing school start times for the health and wellbeing of teens in Aotearoa.

The under-acknowledged malleability of secondary school start times may be a lever towards addressing poor sleep, particularly the sleep deprivation that many adolescents living in Aotearoa New Zealand experience on a daily basis. Scrutinising morning school start times has not been prioritised in terms of a logical, modifiable way to counteract sleep deprivation in adolescents in Aotearoa. Importantly, later start times align with adolescents' natural sleep-wake biology that shifts at puberty to favour later bedtimes, meaning they naturally need to wake later in the morning. In this viewpoint we argue that a later school start time (no earlier than 9:45 am) every day for senior secondary school students is an attractive, non-stigmatising approach to address adolescent sleep. Increased sleep also has the potential to favourably impact multiple areas of adolescents' health and wellbeing, as well as school success. In fact, we argue that later school start times are a public health imperative to address the sleep and mental health issues faced by youth in Aotearoa today.

Social Jetlag and Cardiometabolic Risk in Preadolescent Children.

Objective: Childhood cardiometabolic disease risk (CMD) has been associated with short sleep duration. Its relationship with other aspects of sleep should also be considered, including social jetlag (SJL) which represents the difference between a person's social rhythms and circadian clock. This study investigated whether childhood CMD risk is associated with sleep duration, sleep disturbances, and SJL. Study Design: The observational study included 332 children aged 8-10 years (48.5% female). The three independent variables were sleep duration, sleep disturbances, and SJL. SJL was calculated as the variation in hours between the midpoint of sleep during free (weekend) days and work/school days. Eleven cardiometabolic biomarkers were measured, including central blood pressure, lipids, glycated hemoglobin, arterial wave reflection, and glucose. Underlying CMD risk factors were identified using factor analysis. Results: Four underlying CMD risk factors were identified using factor analysis: blood pressure, cholesterol, vascular health, and carbohydrate metabolism. Neither sleep disturbances nor sleep duration were significantly associated with any of the four CMD factors following adjustments to potential confounders. However, SJL was significantly linked to vascular health (p = 0.027) and cholesterol (p = 0.025). Conclusion: These findings suggest that SJL may be a significant and measurable public health target for offsetting negative CMD trajectories in children. Further studies are required to determine biological plausibility.

What Factors Influence the Sleep of On-call Workers?

Objective: On-call work is becoming increasingly common in response to service demands. This study had two aims; 1) describe the demographic profile of on-call workers in Australia, and 2) establish the impacts of on-call work on workers' sleep. Methods: A cross-sectional study was conducted using an online questionnaire completed by Australian on-call workers (n = 228) from various professions. The questionnaire included items on i) demographic and work characteristics, ii) rumination about on-call factors, iii) sleep quantity and quality. Analyses were conducted using mixed effects ordinal regression and multivariable logistic regression. Results: Workers slept <7 hours per night when on-call (80%), and reported sleep was impacted on-call even when no-calls were received (56%). On-call workers rated interruptions to family/leisure time (70%), missing a call (69%), preplanning in case of a call (69%), and not able to make plans (67%) as the main factors they ruminated about. Female on-call workers were more likely to think about the likelihood of being called, report frequent thoughts about what they would need to do if called, and think about interruptions to family/leisure time as a result of a call. Younger workers were more likely to think about the likelihood of being called compared to older adults, however middle-aged workers were less likely to plan for a call compared to younger workers. Conclusions: This study is the first to describe Australia's on-call population, including factors that specifically impact sleep. Future studies should implement tailored education and support strategies to address the unique challenges facing on-call workers.

Sleep and Adiposity in Preadolescent Children: The Importance of Social Jetlag.

BACKGROUND: While short and poor quality sleep have been associated with childhood obesity, no known studies have examined social jetlag. Social jetlag is the discrepancy between an individual's circadian clock and social rhythms, and is measured as the difference in hours between the midpoint of sleep during work/school days and on free (weekend) days. This study investigated the independent associations between sleep duration, sleep disturbances, and social jetlag with adiposity in children. METHODS: A cross-sectional study, including 341 children (50% female) aged 8-10 years. Five dependent variables: body fat (%), fat mass (kg), fat mass index (FMI, kg/m2), waist to hip ratio, and body mass index (kg/m2). Three independent variables: average sleep duration, sleep disturbances, and social jetlag. RESULTS: Following adjustment for confounders, sleep duration was not associated with any variable, and sleep disturbances were associated with FMI (ß = 0.047, 95% CI: 0.002, 0.093 kg/m2), while social jetlag was associated with all five adiposity variables, including an absolute 3% greater body fat (ß = 2.963, 95% CI: 0.40, 5.53%) per 1 hour of social jetlag. CONCLUSIONS: Social jetlag may be an important and measurable public health target in children.

Preparing Safety Cases for Operating Outside Prescriptive Fatigue Risk Management Regulations.

INTRODUCTION: Transport operators seeking to operate outside prescriptive fatigue management regulations are typically required to present a safety case justifying how they will manage the associated risk. This paper details a method for constructing a successful safety case. METHODS: The method includes four elements: 1) scope (prescriptive rules and operations affected); 2) risk assessment; 3) risk mitigation strategies; and 4) monitoring ongoing risk. A successful safety case illustrates this method. It enables landing pilots in 3-pilot crews to choose the second or third in-flight rest break, rather than the regulatory requirement to take the third break. Scope was defined using a month of scheduled flights that would be covered (N = 4151). These were analyzed in the risk assessment using existing literature on factors affecting fatigue to estimate the maximum time awake at top of descent and sleep opportunities in each break. Additionally, limited data collected before the new regulations showed that pilots flying at landing chose the third break on only 6% of flights. RESULTS: A prospective survey comparing subjective reports (N = 280) of sleep in the second vs. third break and fatigue and sleepiness ratings at top of descent confirmed that the third break is not consistently superior. The safety case also summarized established systems for fatigue monitoring, risk assessment and hazard identification, and multiple fatigue mitigation strategies that are in place. DISCUSSION: Other successful safety cases have used this method. The evidence required depends on the expected level of risk and should evolve as experience with fatigue risk management systems builds.Gander P, Mangie J, Wu L, van den Berg M, Signal L, Phillips A. Preparing safety cases for operating outside prescriptive fatigue risk management regulations. Aerosp Med Hum Perform. 2017; 88(7):688-696.

Environmental and behavioural factors associated with school children's sleep in Aotearoa/New Zealand.

AIM: To collect objective and subjective sleep data on 6- to 8-year-old children across the week and to identify factors within the family environment associated with sleep differences. METHODS: Data were collected (n = 52) using actigraphy and diaries for 7 consecutive days and nights and a questionnaire incorporating the Children's Sleep Habits Questionnaire was completed by parents. RESULTS: Children's actigraphic sleep periods averaged 10 h on school nights and 9.5 h on non-school nights and parents over-estimated children's sleep compared with actigraphy. One third (37%) of children had potential sleep problems. Children who shared a bedroom (31%) had shorter sleep onset latencies and those who consumed caffeinated drinks (33%) went to sleep and awoke later. Increased screen time was associated with later bedtimes on school nights and children with screens in bedrooms (12%) went to bed later and slept less on school nights, and had higher Children's Sleep Habits Questionnaire scores. Children living with a shift-working adult (27%) slept longer on non-school nights and had shorter sleep onset latencies on school nights. CONCLUSIONS: It is important to consider children's sleep within the wider family context and to be aware that parents may over-estimate their children's sleep. Simple strategies to promote sleep health in clinical settings or education programmes include regular weekend bedtimes that align with those on school nights, removing technology from bedrooms and minimising caffeine consumption. An awareness of potential sleep differences associated with shift-working adults may ensure children are supported to have consistent sleep routines that promote adequate sleep.

Does the circadian clock drift when pilots fly multiple transpacific flights with 1- to 2-day layovers?

On trips with multiple transmeridian flights, pilots experience successive non-24 h day/night cycles with circadian and sleep disruption. One study across a 9-day sequence of transpacific flights (no in-flight sleep, 1-day layovers between flights) reported an average period in the core body temperature rhythm of 24.6 h (circadian drift). Consequently, pilots were sometimes flying through the circadian performance nadir and had to readapt to home base time at the end of the trip. The present study examined circadian drift in trip patterns with longer flights and in-flight sleep. Thirty-nine B747-400 pilots (19 captains, 20 first officers, mean age = 55.5 years) were monitored on 9- to 13-day trips with multiple return flights between East Coast USA and Japan (in 4-pilot crews) and between Japan and Hawaii (in 3-pilot crews), with 1-day layovers between each flight. Measures included total in-flight sleep (actigraphy, log books) and top of descent (TOD) measures of sleepiness (Karolinska Sleepiness Scale), fatigue (Samn-Perelli Crew Status Check) and psychomotor vigilance task (PVT) performance. Circadian rhythms of individual pilots were not monitored. To detect circadian drift, mixed-model analysis of variance examined whether for a given flight, total in-flight sleep and TOD measures varied according to when the flight occurred in the trip sequence. In addition, sleep propensity curves for pre-trip and post-trip days were examined (Chi-square periodogram analyses). Limited data suggest that total in-flight sleep of relief crew at landing may have decreased across successive East Coast USA-Japan (flights 1, 3, 5 or 7; median arrival 03:45 Eastern Daylight Time (EDT)). However, PVT response speed at TOD was faster on East Coast USA-Japan flights later in the trip. On these flights, circadian drift would result in flights later in the trip landing closer to the evening wake maintenance zone, when sleep is difficult and PVT response speeds are fastest. On Japan-East Coast USA flights (flights 2, 4, 6 or 8; median arrival time 14:52 EDT), PVT response speeds were slower on flight 8 than on flight 2. Circadian drift would move these arrivals progressively earlier in the SCN pacemaker cycle, where PVT response speeds are slower. Across the five post-trip days, 12 pilots (Group A) immediately resumed their pre-trip sleep pattern of a single nocturnal sleep episode; 9 pilots (Group B) had a daytime nap on most days that moved progressively earlier until it merged with nocturnal sleep and 17 pilots (Group C) had nocturnal sleep and intermittent naps. Chi-square periodogram analyses of the sleep propensity curves for each group across baseline and post-trip days suggest full adaptation to EDT from post-trip day 1 (dominant period = 24 h). However, in Groups B and C, the patterns of split sleep post-trip compared to pre-trip suggest that this may be misleading. We conclude that the trends in total in-flight sleep and significant changes in PVT performance speed at TOD provide preliminary evidence for circadian drift, as do persistent patterns of split sleep post-trip. However, new measures to track circadian rhythms in individual pilots are needed to confirm these findings.

Genotype vs. Phenotype and the Rise of Non-Communicable Diseases: The Importance of Lifestyle Behaviors During Childhood.

Despite continued research and growing public awareness, the incidence of non-communicable diseases (NCD) continues to accelerate. While a person may have a genetic predisposition to certain NCDs, the rapidly changing epidemiology of NCDs points to the importance of environmental, social, and behavioural determinants of health. Specifically, three lifestyle behaviours expose children to important environmental cues and stressors: physical activity, nutritional intake, and sleep behaviour. Failure to expose children to proper gene-environment interactions, through the aforementioned lifestyle behaviours, can and will predispose children to the development of NCDs. Reengineering the environments of children can induce a paradigm shift, from a predominantly biomedical health model of treating symptomology, to a more holistic model based on encouraging appropriate behavioral decisions and optimal health.

Pre-Adolescent Cardio-Metabolic Associations and Correlates: PACMAC methodology and study protocol.

INTRODUCTION: Although cardiovascular disease is typically associated with middle or old age, the atherosclerotic process often initiates early in childhood. The process of atherosclerosis appears to be occurring at an increasing rate, even in pre-adolescents, and has been linked to the childhood obesity epidemic. This study will investigate the relationships between obesity, lifestyle behaviours and cardiometabolic health in pre-pubescent children aged 8-10 years, and investigates whether there are differences in the correlates of cardiometabolic health between Maori and Caucasian children. Details of the methodological aspects of recruitment, inclusion/exclusion criteria, assessments, statistical analyses, dissemination of findings and anticipated impact are described. METHODS AND ANALYSIS: Phase 1: a cross-sectional study design will be used to investigate relationships between obesity, lifestyle behaviours (nutrition, physical activity/fitness, sleep behaviour, psychosocial influences) and cardiometabolic health in a sample of 400 pre-pubescent (8-10 years old) children. Phase 2: in a subgroup (50 Caucasian, 50 Maori children), additional measurements of cardiometabolic health and lifestyle behaviours will be obtained to provide objective and detailed data. General linear models and logistic regression will be used to investigate the strongest correlate of (1) fatness; (2) physical activity; (3) nutritional behaviours and (4) cardiometabolic health. ETHICS AND DISSEMINATION: Ethical approval will be obtained from the New Zealand Health and Disabilities Ethics Committee. The findings from this study will elucidate targets for decreasing obesity and improving cardiometabolic health among preadolescent children in New Zealand. The aim is to ensure an immediate impact by disseminating these findings in an applicable manner via popular media and traditional academic forums. Most importantly, results from the study will be disseminated to participating schools and relevant Maori health entities.

Circadian adaptation of airline pilots during extended duration operations between the USA and Asia.

This study tracked circadian adaptation among airline pilots before, during, and after trips where they flew from Seattle (SEA) or Los Angeles (LAX) to Asia (7--9 time zones westward), spent 7--12 d in Asia, and then flew back to the USA. In Asia, pilots' exposures to local time cues and sleep opportunities were constrained by duty (short-haul flights crossing ≤ 1 time zone/24 h). Fourteen captains and 16 first officers participated (median age = 56 versus 48 yrs, p.U) < 0.001). Their sleep was monitored (actigraphy, duty/sleep diaries) from 3 d pre-trip to 5 d post-trip. For every flight, Karolinska Sleepiness and Samn-Perelli Fatigue scales and 5-min psychomotor vigilance task (PVT) tests were completed pre-flight and at top of descent (TOD). Participants had ≥ 3 d free of duty prior to outbound flight(s). From 72--24 h prior to departure (baseline sleep), mean total sleep/24 h (TST) = 7.00 h (SD = 1.18 h) and mean sleep efficiency = 87% (SD = 4.9%). Most pilots (23/30) flew direct to and from Asia, but 7 LAX-based pilots flew via a 1-d layover in Honolulu (HNL). On flights with ≥ 2 pilots, mean total in-flight sleep varied from 0.40 to 2.09 h outbound and from 0.74 to 1.88 h inbound. Duty patterns in Asia were variable, with ≤ 2 flights/d (mean flight duration = 3.53 h, SD = 0.53 h). TST on days 17 in Asia did not differ from baseline (p.F) = 0.2031). However, mean sleep efficiency was significantly lower than baseline on days 5--7 (p.F) = 0.0041). More pilots were on duty between 20:00 and 24:00 h on days 57 (mean = 21%) than on days 24 (mean = 14%). Sleep propensity distribution phase markers and chi-square periodogram analyses suggest that adaptation to local time was complete by day 4 in Asia. On pre-flight PVT tests in Asia, the slowest 10% of responses improved for flights departing 14:00--19:59 h (p.F) = 0.0484). At TOD, the slowest 10% of responses improved across days for flights arriving 14:00--19:59 h (p.F) = 0.0349) and 20:00--01:59 h (p.F) = 0.0379). Sleepiness and fatigue ratings pre-flight and at TOD did not change across days in Asia. TST on post-trip day 1 was longer than baseline (estimated mean extension = 1.68 h; adjusted p(t) < 0.0001). On all post-trip days, sleep efficiency was comparable to baseline. Sleep propensity distribution phase markers and chi-square periodogram analyses suggest complete readaptation in 12 d. Two opposing influences appeared to affect sleep and PVT performance across days in Asia: progressive circadian adaptation to local time and increasing duty during local night, which displaced sleep from the optimal physiological time. Cumulative sleep restriction across the return flight may explain the large rebound in TST on day 1 post-trip. Thereafter TST, sleep efficiency, and sleep timing suggest that readaptation was complete. Rapid post-trip readaptation may be facilitated by pilots having unconstrained nocturnal sleep opportunities, coupled with stronger patterns of family and social cues than in Asia.

Sleep and sleepiness of fishermen on rotating schedules.

Seafaring is a hazardous occupation with high death and injury rates, but the role of seafarer fatigue in these events is generally not well documented. The International Maritime Organization has identified seafarer fatigue as an important health and safety issue. Most research to date has focused on more regularly scheduled types of operations (e.g., merchant vessels, ferries), but there is relatively little information on commercial fishing, which often involves high day-to-day and seasonal variability in work patterns and workload. The present study was designed to monitor the sleep and sleepiness of commercial fishermen at home and during extended periods at sea during the peak of the hoki fishing season, with a view to developing better fatigue management strategies for this workforce. Sleep (wrist actigraphy and sleep diaries) and sleepiness (Karolinska Sleepiness Scale [KSS] before and after each sleep period) of 20 deckhands were monitored for 4-13 days at home and for 5-9 days at sea while working a nominal 12 h on/6 h off schedule. On the 12 h on/6 hoff schedule, there was still a clear preference for sleep at night. Comparing the last three days at home and the first three days at sea showed that fishermen were more likely to have split sleep at sea (Wilcoxon signed ranks p < 0.001), but the median sleep/24 h did not differ significantly by location (5.9 h at sea vs. 6.7 h at home). However, on 23% of days at sea, fishermen obtained < 4 h total sleep/24 h, compared to 3% of days at home ( p(chi 2) < 0.01). Sleep efficiency, mean activity counts/min sleep, and subjective ratings of sleep quality did not differ significantly between the last three days at home and the first three days at sea. However, sleepiness ratings remained higher after sleep at sea (Wilcoxon signed ranks p < 0.05), with fishermen having post-sleep KSS ratings >or= 7 on 24% of days at sea vs. 9% of days at home (Wilcoxon signed ranks p < 0.01). This work adds to the limited number of studies that objectively monitored the sleep of seafarers. It has the strength of operational fidelity but the weakness that large inter- and intra-individual variability in sleep, combined with the small sample size, limited the power of the study to detect statistically significant differences between sleep at home and at sea. The clear preference for sleep at night during the 12 h on/6 h off schedule at sea is consistent with the expectation that this 18 h duty/rest cycle is outside the range of entrainment of the circadian pacemaker. High levels of acute sleep loss, and residual sleepiness after sleep, were much more common at sea than at home. The longer duration of trips during the peak of the fishing season increases the risk of performance impairment due to greater cumulative sleep loss than would be expected on typical three-day trips. Key fatigue management strategies in this environment include that fishermen report to work as well rested as possible. Once at sea, the day-to-day variability in activities due to uncontrollable factors, such as fishing success, repairing gear, and weather conditions, mean that contingency planning is required for managing situations where the entire crew have experienced long periods of intensive work with minimum recovery opportunities.

Who is too old for shift work? Developing better criteria.

Demographic and social trends in industrialized countries are expected to lead to increasing numbers of older shift workers, raising concerns about possible health and safety risks. For older night workers, the International Labour Organization has recommended options for transferring to day work or early retirement, but few States have adopted these measures. For commercial air transport pilots, the International Civil Aviation Organization has implemented a series of regulatory measures that could manage the risks associated with aging, including a mandatory retirement age, regular medical assessments for fitness to fly, and limits on the duration of duty and rest. Each of these approaches has strengths and weaknesses. The mandatory retirement age is effectively arbitrary, has been controversial, and was recently increased from 60 to 65 yrs for one member of a two-person cockpit crew. Medical assessments offer a more individualized approach, but to improve safety, they must address aspects of health and physical or mental function that affect work performance and safety outcomes. The traditional focus has been on cardiovascular risk factors, although cardiac incapacitation is not a cause of accidents in a two-person cockpit aircraft. On the other hand, while pilot fatigue is an acknowledged cause of accidents, there is currently no requirement to consider issues associated with fatigue or sleep problems in fitness-to-fly medical assessments. Older long-haul pilots show greater sleep fragmentation than their younger colleagues and those in the general population. Sleep becomes more fragmented with increasing age, but the functional significance of this remains unclear. Among younger adults, experimental sleep fragmentation leads to increased sleepiness and degradation of performance and mood. Greater sleep loss is reported by older long-haul pilots, as well as other older shift workers, compared to younger people working similar duty patterns. Experimental sleep restriction causes a degradation of performance and mood that is cumulative and dose-dependent. In addition, a recent large-scale flight simulation study indicates that the duration of sleep obtained by individual pilots is an independent predictor of crew performance in a two-person cockpit. Based on these considerations, we propose that fatigue and sleep-related issues should become a standard part of fitness-for-work medical assessments, particularly for older shift workers. A multi-layered approach is proposed, with a routine structured sleep history leading to referral to specialist sleep services where appropriate. Criteria for specialist referral and medical retirement should be related to the workplace risk represented by an older worker. Additional research is needed to develop and validate sleep-related criteria for assessing fitness for work. For example, a better understanding of the effects of sleep fragmentation on the waking function of older workers might lead to a fragmentation threshold for fitness for work. The potential negative effects of unemployment and early retirement also need to be taken into account when considering the options for managing the occupational health and safety needs of older shift workers.