The Cost of Inadequate Sleep among On-Call Workers in Australia: A Workplace Perspective

Move the night way: how can physical activity facilitate adaptation to shift work?

Shift work, involving night work, leads to impaired sleep, cognition, health and wellbeing, and an increased risk of occupational incidents. Current countermeasures include circadian adaptation to phase shift circadian biomarkers. However, evidence of real-world circadian adaptation is found primarily in occupations where light exposure is readily controlled. Despite this, non-photic adaptation to shift work remains under researched. Other markers of shift work adaptation exist (e.g., improvements in cognition and wellbeing outcomes) but are relatively unexplored. Timeframes for shift work adaptation involve changes which occur over a block of shifts, or over a shift working career. We propose an additional shift work adaptation timeframe exists which encompasses acute within shift changes in markers of adaptation. We also propose that physical activity might be an accessible and cost-effective countermeasure that could influence multiple markers of adaptation across three timeframes (Within Shift, Within Block, Within Work-span). Finally, practical considerations for shift workers, shift work industries and future research are identified.

Differences in shift and work-related patterns between metropolitan and regional/rural healthcare shift workers and the occupational health and safety risks

OBJECTIVES

To explore if there are differences in shift patterns and work-related factors between metropolitan and regional/rural healthcare shift workers and their risk of poor sleep and mental health. Furthermore, explore whether these factors impact on medical errors, workplace and car/near car accidents.

DESIGN

A cross-sectional study.

SETTING

An anonymous online survey of healthcare shift workers in Australia.

PARTICIPANTS

A total of 403 nurses, midwives and paramedics completed the survey.

MAIN OUTCOME MEASURES

Sample characteristics, employment location, shift work-related features, sleep and mental health measurements, workplace accidents, medical errors and car/near car accident post shift.

RESULTS

Regional/rural healthcare shift workers were significantly older, had more years' experience, worked more nights, on-call and hours per week. Those in metropolitan areas took significantly longer (minutes) to travel to work, had higher levels of anxiety, increased risk of shift work disorder, reported significantly more workplace accidents and were more likely to have a car/near car accident when commuting home post shift. Both groups reported ~25% having a medical error in the past year. Workplace accidents were related to more on-call shifts and poor sleep quality. Medical errors were associated with fewer years' experience, more evening shifts and increased stress. Car accidents were associated with metropolitan location and increased depression.

CONCLUSION

Differences in work-related factors between metropolitan and regional/rural healthcare shift workers were observed. Some of these factors contributed to occupational health and safety risks. Further exploration is needed to understand how to reduce occupational health and safety risks, and improve employee and patient safety both in both regional/rural and metropolitan areas.

Healthy sleep practices for shift workers: consensus sleep hygiene guidelines using a Delphi methodology

STUDY OBJECTIVES

The unique requirements of shift work, such as sleeping and working at variable times, mean that current sleep hygiene guidelines may be inappropriate for shift workers. Current guidelines may also contradict fatigue management advice (e.g. advising against daytime napping). The present study utilized a Delphi methodology to determine expert opinion regarding the applicability of current guidelines for shift workers, the appropriateness of the term "sleep hygiene," and develop tailored guidelines for shift workers.

METHODS

The research team reviewed current guidelines and existing evidence to draft tailored guidelines. Seventeen individual guidelines, covering sleep scheduling, napping, sleep environment, bedtime routine, substances, light exposure, diet, and exercise were drafted. Experts from sleep, shift work, and occupational health fields (n = 155) were invited to review the draft guidelines using a Delphi methodology. In each round, experts voted on individual guidelines, with 70% agreement considered consensus. Where consensus was not reached, written feedback from experts was discussed and incorporated into subsequent iterations.

RESULTS

Of the experts invited, 68 (44%) agreed to participate, with 55 (35%) completing the third (final) round. Most experts (84%) agreed that tailored guidelines were required for shift workers. Consensus was reached on all guidelines after three rounds. One additional guideline (sleep inertia) and an introductory statement were developed, resulting in a final set of 18 individual guidelines, termed "healthy sleep practices for shift workers."

CONCLUSIONS

This is the first study to develop tailored sleep hygiene guidelines for shift workers. Future research should investigate the acceptability and effectiveness of these guidelines amongst shift workers.

Sleep and mental health in recruit paramedics: a 6-month longitudinal study

STUDY OBJECTIVES

To explore potential relationships and longitudinal changes in sleep and mental health in recruit paramedics over the first 6 months of work, and whether sleep disturbances pre-emergency work predict future mental health outcomes.

METHODS

Participants (N = 101, 52% female, Mage = 26 years) completed questionnaires prior to (baseline), and after 6 months of emergency work to assess for symptoms of insomnia, obstructive sleep apnea, post-traumatic stress disorder (PTSD), depression, anxiety, and trauma exposure. At each timepoint, participants also completed a sleep diary and wore an actigraph for 14 days to assess sleep patterns. Correlations between baseline sleep and mental health were conducted and changes in these variables across timepoints were examined using linear mixed models. Hierarchical regressions assessed whether sleep at baseline predicted mental health at follow-up.

RESULTS

Insomnia and depression symptoms, and total sleep time increased while sleep onset latency decreased across the first 6 months of emergency work. Participants experienced an average of 1 potentially traumatic event during the 6-month period. Baseline insomnia predicted increased depression symptoms at the 6-month follow-up, while baseline wake after sleep onset predicted follow-up PTSD symptoms.

CONCLUSION

Results highlight an increase in insomnia and depression across the initial months of emergency work, while sleep disturbances before emergency work were identified as potential risk factors for the development of depression and PTSD among paramedics in their early career. Screening and early interventions targeting poor sleep at the beginning of emergency employment may assist in reducing the risk of future mental health outcomes in this high-risk occupation.

Rise and shine: The use of polychromatic short-wavelength-enriched light to mitigate sleep inertia at night following awakening from slow-wave sleep

Sleep inertia is the brief period of performance impairment and reduced alertness experienced after waking, especially from slow-wave sleep. We assessed the efficacy of polychromatic short-wavelength-enriched light to improve vigilant attention, alertness and mood immediately after waking from slow-wave sleep at night. Twelve participants (six female, 23.3 ± 4.2 years) maintained an actigraphy-confirmed sleep schedule of 8.5 hr for 5 nights, and 5 hr for 1 night prior to an overnight laboratory visit. In the laboratory, participants were awakened from slow-wave sleep, and immediately exposed to either dim, red ambient light (control) or polychromatic short-wavelength-enriched light (light) for 1 hr in a randomized crossover design. They completed a 5-min Psychomotor Vigilance Task, the Karolinska Sleepiness Scale, and Visual Analogue Scales of mood at 2, 17, 32 and 47 min after waking. Following this testing period, lights were turned off and participants returned to sleep. They were awakened from their subsequent slow-wave sleep period and received the opposite condition. Compared with the control condition, participants exposed to light had fewer Psychomotor Vigilance Task lapses (χ² [1] = 5.285, p = 0.022), reported feeling more alert (Karolinska Sleepiness Scale: F_1,77  = 4.955, p = 0.029; Visual Analogue Scale_alert : F_1,77  = 8.226, p = 0.005), and reported improved mood (Visual Analogue Scale_cheerful : F_1,77  = 8.615, p = 0.004). There was no significant difference in sleep-onset latency between conditions following the testing period (t₁₀  = 1.024, p = 0.330). Our results suggest that exposure to polychromatic short-wavelength-enriched light immediately after waking from slow-wave sleep at night may help improve vigilant attention, subjective alertness, and mood. Future studies should explore the potential mechanisms of this countermeasure and its efficacy in real-world environments.

Work schedule and seasonal influences on sleep and fatigue in helicopter and fixed-wing aircraft operations in extreme environments

Sleep and fatigue were investigated in aviation search and rescue, firefighting, emergency medical services and offshore transfer operations in 210 participants, for 21 days each, across 17 datasets in seven countries. Sleep data were collected using wrist-worn actigraphs and sleep diaries. Sustained attention was assessed using a 5-min Psychomotor Vigilance Task (PVT). Duty information was provided from corporate IT systems. Despite the number of 24 h operations, most work occurred during daytime hours, and most sleep occurred at night. There were seasonal changes in work and sleep patterns, with naps used to augment total sleep time. The proportion of sleep occurring during duty varied from zero to 30%. Differences in PVT response times were trivial to small. Legislation that defines flight, duty time and minimum rest limits assume that sleep is not obtained during duty periods, apart from some napping under Fatigue Risk Management Systems (FRMS). However, especially in cases where the aviation service requires waiting for tasks (e.g. search and rescue, emergency medical response), this assumption may not always hold. FRMS should accommodate different modes of working that safely facilitate sleep during duty time where appropriate.

On-call work and sleep: the importance of switching on during a callout and switching off after a call

Due to the unpredictable nature of working time arrangements, on-call workers experience regular disruption to sleep, particularly if woken by calls. Sleep disruption can impact long term physical and mental health, next day performance, and importantly, performance immediately after waking. To reduce the impact of performance impairments upon waking (i.e., reducing sleep inertia), research has investigated strategies to promote alertness (e.g., bright light, caffeine, and exercise). This review puts forth on-call workers who are likely to return to sleep after a call, it is also important to consider the impact of these sleep inertia countermeasures on subsequent sleep. Future research should build on the preliminary evidence base for sleep inertia countermeasures by examining the impact on subsequent sleep. This research is key for both supporting alertness and performance during a call ("switching on") and for allowing the on-call worker to return to sleep after a call ("switching off").

A survey of train driver schedules, sleep, wellbeing, and driving performance in Australia and New Zealand

Train drivers work long hours on 24 h schedules and many factors impact their fatigue risk at work, creating a clear imperative for good rostering practice. Adopting a systems approach, this study investigated the relationship between multiple interrelated factors (train drivers’ schedule, sleep, wellbeing, and fatigue) and the perceived influence of these factors on train driving performance and safety using an online survey distributed in Australia and New Zealand. In addition to demographics and work schedule, passenger and freight train drivers (n = 751) answered questions about: (1) Sleep duration; (2) wellbeing, including physical and mental health, the extent to which shiftwork causes sleep, social, domestic, and work problems, and (3) the extent to which ten fatigue, health and wellbeing factors in the work and home environment negatively impact their driving performance. The key factor that emerged from analyses, with the largest and most consistent negative effects (and controlling for other factors) was schedule irregularity. Approved rosters were ranked as having the most important impact on day-to-day driving performance, followed by physical and mental health, and outside work factors. Results also suggested that schedule irregularity may amplify the negative impacts of the roster, impaired physical and mental health, and outside work factors on driving performance. As shift variability and schedule irregularity are often poorly represented in existing industry guidance, these results provide evidence for increased reflection on current fatigue management guidelines for train drivers and suggest a need for greater focus on schedule irregularity through the lens of a systems approach.

Informal management of health and safety risks associated with alarm response by Australian firefighters

Fire-fighters use informal strategies to manage risks to health and safety during operations. It is not known whether such strategies are used during the high-risk alarm response period. The aim of this study was to determine if informal risk management strategies are employed by Australian firefighters during the alarm response procedure, and if these strategies differ between salaried and retained personnel. Forty-six metropolitan firefighters (all male; mean age 38 years ± 10 years; 22 salaried; 24 retained) participated in semi-structured group interviews. A general inductive data analysis approach revealed that firefighters use multiple informal risk management strategies. Some similar themes were reported by both salaried and retained personnel, for example leveraging team dynamics, communication about sleep and fatigue, stress adaptation, informal debriefs, and enhancing physical preparedness. These findings could be used by fire services to tailor risk management approaches during the alarm response period. Practitioner summary: Identifying informal risk management strategies firefighters use during alarm response will allow their development, refinement and dissemination, and may help other firefighters and emergency service workers to manage these risks. This qualitative study reveals multiple informal strategies that firefighters employ during alarm response to keep themselves and their team-mates safe.

The impact of a short burst of exercise on sleep inertia

STUDY OBJECTIVES

Determine whether 30 s (s) of exercise performed upon waking can reduce sleep inertia and accelerate an increase in the cortisol awakening response (CAR) and core body temperature (CBT), compared to when sedentary.

METHODS

Fifteen participants (mean age ± SD, 25.9 ± 5.9 years; six females) completed a counterbalanced, repeated measures, in-laboratory study involving three single experimental nights, each separated by a four-night recovery period. Participants were woken following a 2-h nap (2400-0200) and completed a cycling bout of high-intensity (30-s sprint), low-intensity (30 s at 60% maximum heart rate), or no exercise (sedentary). Sleep inertia testing (eight batteries, 15-min intervals) began immediately following and included measures of subjective sleepiness (Karolinska Sleepiness Scale) and cognitive performance tasks (psychomotor vigilance, serial addition and subtraction, and spatial configuration). CBT was measured continuously via an ingestible telemetric capsule. The CAR was determined using salivary cortisol samples collected at 0, 30 and 45 min post-waking. Data were analysed using mixed effects analysis of variance.

RESULTS

There was no difference in cognitive performance or CBT between conditions. Participants felt less sleepy in the high-intensity condition, followed by the low-intensity and sedentary conditions (p = .003). The CAR was greatest in the high-intensity condition, followed by the sedentary condition, and low-intensity condition (p < 0.001), with no differences between the low-intensity and sedentary conditions.

CONCLUSIONS

Those who exercise upon waking should be aware that while they may feel more alert, they may not be performing better than if they had not exercised. Future research should investigate whether exercise of different duration or timing may impact sleep inertia.

Identifying lower limb problems and the types of safety footwear worn in the Australian wine industry: a cross-sectional survey

BACKGROUND

The Australian wine industry is a valuable part of the wider Australian economy worth approximately A$45 billion annually and employs 163,790 people either full time or part time. Australian agricultural industries are amongst the nation's most dangerous workplaces with joint, ligament, muscle and tendon injuries being commonplace along with wounds, lacerations and musculoskeletal diseases. It is therefore important to try and minimise the risk of injuries to workers. The aims of this study were to (1) identify whether lower limb problems occur in the Australian wine industry and (2) identify the types of safety footwear worn.

METHODS

Participants were recruited from the Australian wine industry. The study was a cross-sectional anonymous survey of 82 questions with n = 207 respondents. Questions related to job role performed, types of lower limb problems experienced, level of pain, restriction of activities, types of footwear worn, general health and physical health.

RESULTS

The main working roles were winery (73.4%), vineyard (52.2%), laboratory (39.6%), cellar door (32.4%) and office (8.2%), with 63.3% of participants working in more than one role. Lower back pain was the most commonly reported problem at 56% followed by foot pain (36.7%), knee pain (24.6%), leg pain (21.3%), ankle pain (17.9%), hip pain (15.5%), toe pain (13%) and heel pain (11.1%). The most popular footwear used by participants were elastic sided safety boots, followed by high cut lace up safety boots with side zip. Overall, although the pain experienced was moderate, it did not impact the workers ability to perform their duties and the majority self-reported as being in very good general and physical health.

CONCLUSION

To date no data have been published on the types of lower limb problems or the types of safety footwear worn in the Australian wine industry. This study is the first to demonstrate that elastic sided safety boots were the most popular amongst respondents and that lower limb problems occur with workers. Therefore, further research into the safety footwear used in the Australian wine industry is needed to better support workers health while working in their varied roles and conditions.

Who is 'on-call' in Australia? A new classification approach for on-call employment in future population-level studies

BACKGROUND

On-call research and guidance materials typically focus on 'traditional' on-call work (e.g., emergency services, healthcare). However, given the increasing prevalence of non-standard employment arrangements (e.g., gig work and casualisation), it is likely that a proportion of individuals who describe themselves as being on-call are not included in current on-call literature. This study therefore aimed to describe the current sociodemographic and work characteristics of Australian on-call workers.

METHODS

A survey of 2044 adults assessed sociodemographic and work arrangements. Of this population, 1057 individuals were workforce participants, who were asked to provide information regarding any on-call work they performed over the last three months, occupation type, weekly work hours, and the presence or absence of non-standard work conditions.

RESULTS

Of respondents who were working, 45.5% reported working at least one day on-call in the previous month. There was a high prevalence of on-call work in younger respondents (63.1% of participants aged 18-24 years), and those who worked multiple jobs and more weekly work hours. Additionally, high prevalence rates of on-call work were reported by machinery operators, drivers, community and personal service workers, sales workers, and high-level managers.

CONCLUSIONS

These data suggest that on-call work is more prevalent than previously recorded and is likely to refer to a broad set of employment arrangements. Current classification systems may therefore be inadequate for population-level research. A taxonomy for the classification of on-call work is proposed, incorporating traditional on-call work, gig economy work, relief, or unscheduled work, and out of hours work.

Perception versus Reality: The Relationship between Subjective and Objective Measures of Sleep When On-call under Simulated Laboratory Conditions

BACKGROUND

On-call working arrangements have been shown to negatively impact sleep. However, workers may perceive their sleep to be worse than it actually is. The aim of this study was to compare participants' pre- and post-sleep estimates of sleep duration and sleep quality with objectively measured sleep when on-call under laboratory conditions.

PARTICIPANTS

72 healthy, adult males.

METHODS

Analyses were performed on three interrelated studies, all of which consisted of four nights in a sleep laboratory. Following adaptation and baseline nights were two on-call nights (sleep opportunity 23:00 h - 07:00 h). Before and after each sleep opportunity, participants provided subjective estimates of sleep. Sleep was objectively measured using polysomnography.

RESULTS

Estimated sleep duration (6.74 ± 1.13 h) and sleep onset latency (20.55 ± 14.85 min) were significantly poorer than objectively measured sleep outcomes (sleep duration 7.21 ± 1.25 h; sleep latency 13.20 ± 10.06 min). Of the variance in post-sleep estimated sleep duration, 14% was associated with objectively measured minutes of N3 (R²Δ = 0.55) and REM (R²Δ = 0.75). Additionally, 14% of post-sleep sleep quality estimation variance was associated with minutes of N2 (R²Δ = 0.60) and N3 (R²Δ = 0.79), measured by polysomnography.

CONCLUSIONS

Some objective measures of sleep were associated with subjective estimates of sleep duration and sleep quality. However, individuals may overestimate sleep onset latency and underestimate sleep duration during on-call periods. It may be beneficial for on-call workers to actively reflect on feelings of fatigue/alertness for workplace fatigue management, rather than relying solely on estimates of sleep.

Are Individuals with Low Trait Anxiety Better Suited to On-Call Work?

Research has indicated that individuals with certain traits may be better suited to shiftwork and non-standard working arrangements. However, no research has investigated how individual differences impact on-call outcomes. As such, this study investigated the impact of trait anxiety on sleep and performance outcomes on-call. Seventy male participants (20–35 years) completed an adaptation night, a control night, and two on-call nights in a laboratory. Trait anxiety was determined using the State Trait Anxiety Inventory (STAI) X-2, and participants completed the STAI X-1 prior to bed each night to assess state anxiety. Sleep was measured using polysomnography and quantitative electroencephalographic analysis. Performance was assessed using a 10-min psychomotor vigilance task (PVT) performed each day at 0930, 1200, 1430 and 1700 h. Data pooled from three separate but inter-related studies was used for these analyses. Results indicated that the effects of trait anxiety on state anxiety, sleep and performance outcomes on-call were generally limited. These findings suggest that on-call outcomes are not negatively affected by higher levels of trait anxiety.

The effect of a short burst of exercise during the night on subsequent sleep

When on-call workers wake during the night to perform work duties, they may experience reduced alertness and impaired performance as a result of sleep inertia. After performing their duties, on-call workers may have the opportunity to return to sleep. Thus, it is important that sleep inertia countermeasures do not affect subsequent sleep. Exercise may be a suitable countermeasure; however, the impact on subsequent sleep is untested. Healthy participants (n = 15) completed three conditions in a counterbalanced order: sedentary, low-intensity exercise or high-intensity exercise, performed for 2 min upon awakening. Sleep was recorded 2 hr later using polysomnography, the Karolinska Sleepiness Scale was administered to measure subjective sleepiness, and core body temperature was measured continuously. Results indicate there was no effect of condition on most sleep variables; however, three variables had small differences, with longer total sleep time (p = .006), higher sleep efficiency (p = .006) and shorter N3 latency (p < .001) in the low-intensity exercise condition. There was no difference in subjective sleepiness (p = .124) or core body temperature (p = .216) 90 min after the exercise intervention. These results indicate that using a short burst of exercise to counteract sleep inertia when woken during the night may be a suitable countermeasure for on-call workers who not only need to be alert upon waking but also need quality sleep when returning to bed. Future research could include participants of other ages and health statuses to investigate whether the results are generalizable.

Impacts of Australian Firefighters' On-Call Work Arrangements on the Sleep of Partners

On-call work arrangements are commonly utilised in the emergency services sector and are consistency associated with inadequate sleep. Despite sleep being a common shared behaviour, studies are yet to assess the impact of on-call work on the sleep of co-sleeping partners. This study aimed to investigate whether frequent 24/7 on-call work impacted the sleep and relationship happiness of firefighters' partners. Two key research questions were investigated: (1) Does the frequency of calls impact sleep and relationship happiness? and, (2) Does the (a) sleep quantity and (b) sleep quality of partners impact perceived relationship happiness? A cross-sectional study was conducted using an online questionnaire completed by partners of on-call workers (n = 66; 93% female). The questionnaire included items on (i) sleep quantity and quality, (ii) on-call sleep disturbances and, (iii) relationship happiness. Responses were analysed using logistic regression models. Higher overnight call frequency was associated with greater self-reported levels of inadequate sleep (<7 h per night; p = 0.024). Support for continuance of a firefighter's role was less likely if the partner reported they regularly had trouble falling asleep within 30 min (p < 0.001). There were no other significant relationships between the frequency of calls or other sleep quantity or quality variables and relationship happiness. This study provides important first insights into how firefighters' on-call work arrangements impact partners' sleep. Future research is needed across periods of high and low call demand, using objective measures of sleep to further define the impacts of on-call work on partners' sleep.

The impact of anticipating a stressful task on sleep inertia when on-call

Sleep inertia, the state of reduced alertness upon waking, can negatively impact on-call workers. Anticipation of a stressful task on sleep inertia, while on-call was investigated. Young, healthy males (n = 23) spent an adaptation, control and two counterbalanced on-call nights in the laboratory. When on-call, participants were told they would be woken to a high or low stress task. Participants were not woken during the night, instead were given a 2300-0700 sleep opportunity. Participants slept ∼7.5-h in all conditions. Upon waking, sleep inertia was quantified using the Karolinska Sleepiness Scale and Psychomotor Vigilance and Spatial Configuration Tasks, administered at 15-min intervals. Compared to control, participants felt sleepier post waking when on-call and sleepiest in the low stress compared to the high stress condition (p < .001). Spatial performance was faster when on-call compared to control (p < .001). Findings suggest that anticipating a high-stress task when on-call, does not impact sleep inertia severity.

Predictor of sleep difficulty among community dwelling older populations in 2 African settings

Sleep deprivation is a common phenomenon among older population and is commonly linked to behavioral, physiological, and psychosocial factors. Not much is known about sleep deprivation among older population in Africa. Therefore, in this study we aimed to investigate the basic sociodemographic and psychosocial predictors of self-reported sleep deprivation among older population.In this study we analyzed cross-sectional data on 1495 community dwelling men and women aged 50 years and above. Data were collected from the SAGE Well-Being of Older People Study conducted in South Africa and Uganda. Outcome variable was self-reported sleep difficulty last 30 days. Multivariable logistic regression models were used to identify the variables significantly associated with sleep difficulty.The prevalence of mild-moderate sleep difficulty was 32.6% (27.9, 37.6) and severe/extreme 23.0% (20.3, 26.0) respectively. Multivariable analysis revealed that sleep difficulty was associated with several behavioral, environment, and illness conditions. In South Africa, those who reported dissatisfaction with living condition had 1.592 [1.087, 2.787] times higher odds of reporting mild/moderate sleep difficulty. Poor subjective quality of life (QoL) was associated with higher odds of severe/extreme sleep difficulties (odds ratios [OR] = 4.590, 95% confidence interval [CI] = 2.641, 7.977 for South Africa, and OR = 4.461, 95% CI = 2.048 and 9.716 for Uganda). In Uganda, perceived depression was associated with higher odds of severe/extreme (OR = 2.452, 95% CI = 1.073, 5.602) sleep difficulties among men, and both mild/moderate (OR = 1.717; 95% CI = 1.011, 2.914) and severe/extreme sleep difficulties among women (OR = 2.504, 95% CI = 1.408, 4.453).More than half of the participants had sleep difficulty of certain degrees, emphasising an urgent need for intervention for sleep deprivation in the population. Interventions targeting to promote subjective health, quality of life, and living environment may prove beneficial for improving sleep health in this regard.

Overnight heart rate variability and next day cortisol response during simulated on-call conditions

OBJECTIVE

This study had two specific objectives, 1) to investigate the impact of being on-call on overnight heart rate variability during sleep and; 2) to examine whether being on-call overnight impacted next-day salivary cortisol concentrations.

METHODS

Data are reported from three within-subject laboratory studies (n = 24 in each study) that assessed varying on-call conditions. Healthy male participants (n = 72 total) completed a four-night laboratory protocol, comprising an adaptation night, a control night, and two counterbalanced on-call nights with varying on-call conditions. These on-call conditions were designed to determine the impact of, Study 1: the likelihood of receiving a call (definitely, maybe), Study 2: task stress (high-stress, low-stress), and Study 3: chance of missing the alarm (high-chance, low-chance), on measures of physiological stress. Overnight heart rate variability (HRV) (during sleep) was measured using two-lead electrocardiography, and time- and frequency-domain variables were analysed. Saliva samples were collected at 15-min time intervals from 0700-0800 h to determine cortisol awakening response outcomes and at four daily time points (0930 h, 1230 h, 1430 h, and 1730 h) to assess diurnal cortisol profiles.

RESULTS

There were few differences in HRV measures during sleep across all three studies. The only exception was in Study 1 where the standard deviation of the time interval between consecutive heartbeats and the root mean square of consecutive differences between heartbeats were lower across all sleep stages in the definitely condition, when compared to control. Across all three studies, being on-call overnight also had little impact on next-day cortisol awakening response (CAR), with the exception of Study 2 where the 1) CAR area under the curve with respect to increase was blunted in the high-stress condition, compared to the control and low-stress conditions and, 2) CAR reactivity was higher in low-stress condition, compared with the high-stress condition. In Study 1, diurnal cortisol area under the curve with respect to ground was lower in the on-call conditions (definitely and maybe) when compared to control. There were no differences in diurnal cortisol measures in Study 3.

CONCLUSION

This is the first study to investigate how different aspects of being on-call affect physiological stress responses. Overall, relatively little differences in measures of overnight heart rate variability and next-day cortisol response were recorded in all three studies. Further research utilising real on-call work tasks, not just on-call expectations (as in the current study) will help determine the impact of on-call work on the physiological stress response.

The effects of on-call work on mental health issues among wage workers in the Republic of Korea

On-call workers are often on standby at night or on weekends and are called to perform work when unanticipated incidents occur. However, the effects of on-call duty on the mental health has received little attention. The objective of this study was to investigate the effects of on-call work on mental health problems among Korean wage workers. Korean wage workers (56,553) from the 2011-2014 Korean Working Condition Survey were enrolled. The outcome measures included insomnia or sleep disorder and depression or anxiety disorder. General characteristics, occupational and work environment characteristics were used to adjust for control variables. Among the Korean wage workers, 8.2% (N=4,653) performed on-call duties. On-call workers were more likely to experience insomnia or sleep disturbance (3.8%vs2.4%; p<.0001) and depression or anxiety disorder (2.2%vs1.2%; p<.0001) than those who did not have on-call duties. After adjusting for control variables, the odds ratio (OR) for insomnia or sleep disturbance was 1.56 (95% CI, 1.23-1.99), and the OR for depression or anxiety disorder was 2.23 (95% CI, 1.61-3.08). In conclusion, on-call work was associated with mental health problems in Korean wage workers. Therefore, we need to understand the problems of on-call workers, and try to improve their health care.

Twenty-four-hour pattern of operations-related injury occurrence and severity of off-site/on-call volunteer French firefighters

We assessed the 24-h pattern of operations-related injuries (ORI) experienced by scheduled off-site/on-call French volunteer firefighters (VFF) through analysis of an archival database. Occurrence and severity - evaluated by number of lost work days (LWD) and total medical costs (TMC) - of ORI were explored in terms of risk ratios, respectively, number of ORI/number of service operations (RR_ORI), number of LWD/number of ORI (RS_LWD,) and TMC/number of ORI (RS_TMC). Additionally, the collective work performance of all involved VFF was measured in terms of the lag time (LT) between emergency call-center firefighter-answered communication for service of observer-presumed out-of-hospital cardiac arrest (OHCA) and departure of vehicle from fire station to render aid, designated LT_OHCA. Cosinor and cross-correlation statistical methods were applied. A total of 252 ORI occurred while performing 146,479 service operations. High-amplitude 24 h variation was detected in RR_ORI (p < .003), SR_LWD (p < .001), SR_TMC (p < .012), and LT_OHCA (p < .001), all with nocturnal peak time. Coherence was found between the day/night variation of LT_OHCA and RR_ORI (r = 0.7, p < .0002), SR_LWD (r = 0.5, p < .02), and SR_TMC (r = 0.4, p < .05). This investigation verifies the occurrence and severity of ORI of scheduled off-site/on-call VFF exhibit high-amplitude 24 h patterning with nocturnal excess that closely coincides with their day/night work performance measured by LT_OHCA. These findings, which are essentially identical to ones of a previous study entailing on-site/on-call career firefighters, indicate the need for fatigue management and ORI prevention programs not yet available to VFF, who compose the majority of the field service workforce of French fire departments. Abbreviations:FF: firefighters; CFF: career firefighters; VFF: volunteer firefighters; FD: fire department; LT_OHCA: lag time (LT) response in min:sec between fire department call-center-answered communication for service of presumed out-of-hospital cardiac arrest (OHCA) and departure from fire station of vehicle to render aid; LWD: lost work days; ORI: operations-related injuries; SR_LWD: severity ratio of operations-related injuries in terms of number of lost work days, calculated as number of lost work days/number of operations-related injuries; RR_ORI: risk ratio of operations-related injuries calculated as number of operations-related injuries/number of operations; SR_TMC: severity ratio of operations-related injuries in terms of total medical costs, calculated as total medical costs/number of operations-related injuries; TMC: total medical costs.

The Impact of on-Call Work for Partners' Sleep, Relationship Quality and Daytime Functioning

The on-call schedule is a common work arrangement that allows for the continuance of services during periods of low demand or emergencies. Even though 17%–25% of the world’s population participate in on-call work, the human impacts of on-call are generally poorly described in the literature. Of the studies available on the effects of on-call work on workers, disturbances to sleep duration and sleep quality are the most commonly reported, along with negative sleep-related consequences on sleepiness, fatigue, stress and mood. Research has shown that for couples sharing a bed, disturbances to sleep can impair relationship conflict resolution and reduce relationship quality. In the ‘off-site’ on-call scenario where workers are sleeping at home, their co-sleeping partner may be at risk of sleep disturbances and the subsequent detrimental consequences of this disturbed sleep for themselves and their relationship. To date, few studies have investigated the impact of on-call work for partners’ sleep and the potential sleep-related consequences. Therefore, further studies are needed to specifically address whether on-call work impacts the sleep of partners and whether these sleep disturbances also impact the partner’s daily performance and relationship quality. Our aim was to provide a narrative around the existing, relevant literature that both investigate and inform the potential impact of on-call for workers’ partners’ sleep and related consequences.

Understanding the Differing Impacts of On-Call Work for Males and Females: Results from an Online Survey

On-call work is prevalent worldwide and is associated with adverse outcomes, including disrupted sleep, impaired leisure time, and difficulties in mentally detaching from work. Limited studies specifically explored whether men and women experience on-call differently; therefore, our aim was to investigate whether sex differences exist in terms of both the impacts of and coping strategies to deal with on-call work. On-call workers (n = 228) participated in an online survey to investigate how on-call work impacts domestic, non-domestic, and leisure activities, and coping strategies. Pearson chi-squared analyses were used to determine sex differences for each construct of interest. Results indicated that female respondents were more likely to be responsible for running their household, and reported that being on call disturbed leisure, domestic, and non-domestic activities "a lot/very much". While both males and females adopted engaged coping styles, a greater proportion of males used "problem solving" and a greater proportion of females "talked about their feelings" when managing on-call work. These findings provide valuable insight into how males and females are differentially impacted and cope with on-call work. Further research is required to better understand these impacts, particularly over time, and should include measures such as of quality of life, relationship satisfaction, and physical and mental health outcomes.