Search

Background: Working during the night interferes with the timing of normal daily activities and is associated with an increased risk of chronic diseases. Under controlled experimental conditions, interventions focusing on sleep and nutrition can mitigate the short-term adverse effects of shift work. However, it is unclear how these results translate to real-life, how they can be targeted to individual conditions, and how they relate to long-term health. Therefore, the current study aims to implement a personalized sleep and nutritional intervention among night shift workers in the field., Methods: A non-blinded controlled intervention study is used, consisting of a run-in period, an intervention of 3 months, post-intervention measurements, and a follow-up after 12 months. Three study arms are included: sleep intervention, nutritional intervention, and control group (n = 25 each). Participants are healthy 18-60-year male night shift workers, with at least one year of experience in night shift work. Information from the run-in period will be used to personalize the interventions. The main outcomes are sleep measurements and continuous interstitial glucose levels. Furthermore, general health biomarkers and parameters will be determined to further evaluate effects on long-term health., Discussion: This study aims to mitigate negative health consequences associated with night shift work by introducing two personalized preventive interventions. If proven effective, the personalized interventions may serve as practical solutions that can have a meaningful impact on the sustainable health and employability of night shift workers. This study will thereby contribute to the current need for high-quality data on preventative strategies for night shift work in a real-life context., Trial Registration: This trial has been registered under ClinicalTrials.gov Identifier NCT06147089. Registered 27 November 2023., (© 2024. The Author(s).)

Objective: Shift work causes circadian rhythms to misalign with the demands of the environment, which has been associated with sleep difficulties and cognitive impairments. Although bright light exposure during night shifts can improve circadian alignment, its implementation is often infeasible. Here, we tested whether light exposure in the evening, before the night shift, could improve fatigue, work performance, mood, and sleep., Methods: Fifty-seven healthy nurses who worked full-time rapidly rotating shift schedules completed the study. In a mixed-design randomized controlled trial, participants completed a baseline observation period before following 1 of 2 interventions. The experimental intervention aimed to improve circadian alignment using evening light exposure and morning light avoidance; the control intervention aimed to improve alertness and reduce sleep disturbances by modifying diet. Every morning and evening for 30 days, participants completed measures of fatigue, work-related errors, sleepiness, mood, sleep duration, and sleep quality., Results: Compared to the baseline observation period, the experimental intervention reduced errors by 67%, while the control intervention reduced them by only 5%. This reduction was partially mediated by fatigue; experimental participants reported less fatigue on work days than control participants (d = 0.25 [0.10, 0.38]). The experimental group also showed a small improvement in mood. Both groups showed reductions in fatigue (d = 0.29 [0.20, 0.36]) and sleepiness (d = 0.21 [0.12, 0.28]) as well as a small increase in sleep duration., Conclusions: Interventions based on evening light may be a feasible and effective strategy to reduce fatigue and errors in night-shift workers., Competing Interests: Funding This research was supported by Mitacs (Accelerate award IT16334) and the Canada First Research Excellence Fund, awarded to the Healthy Brains for Healthy Lives initiative (3c-KM-32) at McGill University. MC acknowledges funding from le Fonds de recherche du Québec — Santé (FRQS) and DA acknowledges funding from the Canadian Institutes for Health Research. JO acknowledges funding from the Social Sciences and Humanities Research Council of Canada and FRQS., (Copyright © 2023 National Sleep Foundation. Published by Elsevier Inc. All rights reserved.)

Background: Shift work is commonly associated with health problems resulting from circadian misalignment and sleep restriction. About one in three shift workers is affected by insomnia and up to 90% report regular fatigue and/or sleepiness at the workplace. Epidemiological data shows that shift workers are at increased risk of cardiovascular disease, diabetes, obesity, breast cancer, mental-health problems, and shift-work disorder, which conditions typically lead to reduced work performance, processing errors, accidents at work, absenteeism, and reduced quality of life. Given these widespread and debilitating consequences, there is an urgent need for treatments that help improve the sleep, health, and functional performance of the shift-working population. The most common non-pharmacological recommendations are improved scheduling, bright-light exposure, napping, psychoeducation promoting sleep hygiene, and cognitive-behavioral techniques. The objectives of the present study are to investigate the effects of a multimodal shift-work intervention on perceived fatigue, sleepiness, physical and mental health, sleep parameters, and absenteeism., Methods: A randomized controlled interventional study comparing the two groups each comprising at least 80 drivers of a public transport company, using self-report questionnaires and health checks completed at intake and after 3 and 6 months following the start of the intervention or waiting-list period. The intervention consists of (a) healthy scheduling taking into account shift-rotation direction and speed, chronotype, resting time, and napping; (b) an education program specifically developed for shift workers; and (c) a dedicated information campaign for shift planners. The primary outcome is symptomatic burden in terms of sleepiness, and the key secondary outcome is symptomatic burden in terms of fatigue. Supplementary secondary outcomes are sleep parameters, absenteeism, general and clinical health, changes in mood, and anxiety., Discussion: Expected outcomes are significant improvements on all primary and secondary outcome parameters in the intervention group. To our knowledge, ours is the first randomized controlled study to systematically investigate the effects of a multimodal program on multiple health, sleep, and performance parameters in shift workers. Our research also aims at providing evidence-based practice guidelines for healthy scheduling in general and thus contribute to diminishing the serious health and economic burdens associated with shift work overall., Trial Registration: EDGE registration number: 000339., Clinicaltrials: gov NCT05452096., (© 2022. The Author(s).)

Objective: Pilot test the effectiveness of an online training program for managing shift work and long work hours., Method: Fifty-seven officers from across the United States participated for 12 weeks in a pre-test, training intervention, post-test design assessing the following measures: sleep using actigraphy, diaries, and surveys; knowledge and feedback about the training using surveys., Results: After the training, actigraphy data showed significant reductions in sleep latency and awakenings during sleep. Survey data showed reductions in sleepiness, difficulty staying awake during the day, and difficulty getting things done. Frequency of nightmares also decreased. Participant's knowledge about sleep improved and satisfaction with the training was high., Conclusion: Participants were satisfied with the training and showed objective improvements in their sleep and subjective improvements in feelings when awake. This research will help inform interventions to improve police officer health and wellness., Competing Interests: The authors report no conflicts of interest., (Copyright © 2022 American College of Occupational and Environmental Medicine.)

Study Objectives: While insomnia and sleepiness symptoms are common in shift workers, 20%-30% experience more severe symptoms and meet the criteria for shift work disorder (SWD). SWD can lead to impairments in cognitive function, physical and mental health, and reduced productivity and increased risk of workplace injury. The aim of this study was to deliver and evaluate a shift work individual management coaching program, focusing on sleep education, promoting good sleep hygiene, and providing individualized behavioral strategies to cope with shift schedules., Methods: A clustered randomized controlled trial of sleep education and sleep disorders screening was undertaken, based on hospital wards at a tertiary hospital in Melbourne, Australia. Participants identified as high risk for SWD underwent one of two 8-week programs, a shift work individualized management program, or an active control. The primary outcome was ward-based sick leave. Secondary outcomes were SWD risk, sleep hygiene, insomnia, depression, and anxiety. A total of 149 nurses, across 16 wards (96% female, 34.66 ± 11.99 years) completed both baseline and follow-up questionnaires (23.9% were high risk SWD)., Results: There was no significant reduction in sick leave between intervention and control wards (mean difference = 1.2 days, P = .063). Improvements were seen in insomnia ( P < .0001) and depression (intervention, P ≤ .0001, control, P = .023) in both groups, but were not significantly different between programs. Anxiety ( P = .001. control P = .079) and Functional Outcomes of Sleep Questionnaire 10 ( P = .001 control P = .056) improved only for the intervention., Conclusions: This SWD intervention trial did not reduce sick leave compared to the active control but there was an improvement. Improvements in sleep hygiene, insomnia, depression, and anxiety severity were seen for both groups. Future intervention trials should consider including both sleep and mental health interventions, strategies to avoid between group contamination and the duration of programs for optimal behavioral modification., Clinical Trial Registration: Registry: Australian New Zealand Clinical Trials Registry; Name: Sleep Health Management for Healthcare Workers; URL: https://anzctr.org.au/Trial/Registration/TrialReview.aspx?ACTRN=12616000369426; Identifier: ACTRN12616000369426., Citation: Booker LA, Sletten TL, Barnes M, et al. The effectiveness of an individualized sleep and shift work education and coaching program to manage shift work disorder in nurses: a randomized controlled trial. J Clin Sleep Med . 2022;18(4):1035-1045., (© 2022 American Academy of Sleep Medicine.)

Graduate medical education (GME) training commonly requires residents and fellows to engage in night float shift work. This review aims to assess the effectiveness of interventions for trainees when preparing for, completing, and recovering from working night float shifts. We reviewed all available studies published prior to September 2019 using PubMed, Scopus, CINAHL, the Cochrane library, PsycINFO, and Google Scholar databases. We included all original, primary research articles assessing either non-pharmacological or pharmacological interventions on the chronobiological and physiological effects of night float shift work among GME trainees. Five studies (n = 179 patients) met inclusion criteria. Interventions included melatonin in the morning before sleep after night float shifts, napping during night float shifts, modafinil after a night of sleep deprivation, and caffeinated energy drinks after 6 consecutive night float shifts. Melatonin improved one measure of attention. A 2-hr nap was associated with improved speed related to task switching. Modafinil improved performance in tests of cognition. Caffeinated energy drinks led to improvement in select driving performance variables and reaction time. Effect sizes for outcome variables were calculated. Heterogeneity among the studies precluded combining the data in a meta-analysis. According to GRADE criteria, the quality of the evidence in these studies was low or very low. Our findings suggest GME trainees may benefit from utilising a limited number of interventions when preparing for or recovering from night float shift work. More investigation is needed to identify interventions that could help GME trainees adapt to and recover from working night float shifts., (© 2020 European Sleep Research Society.)

This study aimed to investigate the association between work organization and the trajectories of insomnia patterns among night shift workers in a hospital. The health examination data of hospital workers, recorded from January 2014 to December 2018, were collected; 6765 records of 2615 night shift workers were included. Insomnia was defined as a score of ≥ 15 on the Insomnia Severity Index (ISI). Participants were categorized into five groups according to insomnia patterns derived from the analysis of their ISI scores. Work organization and socio-demographic characteristics were also investigated. Generalized estimating equation models and linear mixed models were constructed to analyze the longitudinal data. Of the total participants, 53.0% reported insomnia at least once during the follow-up period. The lack of nap opportunities and work-time control was associated with the occurrence of insomnia, whereas more than 5 years of shift work experience was related to the resolution of insomnia. All work-related factors were significantly related to insomnia risk; however, the effects were not significant in the sustained insomnia group. Although sleep problems are inevitable in night shift workers, well-designed work schedules and better work organization can help reduce the occurrence of insomnia among them.

Objectives: Recent studies have demonstrated that first-line nurses involved in the coronavirus disease-2019 (COVID-19) crisis may experience sleep disturbances. As breathing relaxation techniques can improve sleep quality, anxiety, and depression, the current study aimed to evaluate the effectiveness of diaphragmatic breathing relaxation training (DBRT) for improving sleep quality among nurses in Wuhan, China during the COVID-19 outbreak., Methods: This study used a quasi-experimental (before and after) intervention strategy, with 151 first-line nurses from four wards in Leishenshan hospital. The Pittsburgh Sleep Quality Index (PSQI), Self-Rating Anxiety Scale (SAS), and Self-Rating Depression Scale (SDS) to evaluate the effectiveness of DBRT before and after the intervention. Data were examined using the Shapiro-Wilk test, Levene's test, and paired t-test., Results: A total of 140 nurses completed the DBRT sessions. First-line nurses achieved significant reductions in global sleep quality (p < 0.01), subjective sleep quality (p < 0.001), sleep latency (p < 0.01), sleep duration (p < 0.001), sleep disturbances (p < 0.001), habitual sleep efficiency (p = 0.015), daytime dysfunction (p = 0.001), and anxiety (p = 0.001). There were no significant reductions in the use of sleeping medication (p = 0.134) and depression (p = 0.359)., Conclusion: DBRT is a useful non-pharmacological treatment for improving sleep quality and reducing anxiety among first-line nurses involved in the COVID-19 outbreak. The study protocol was clinically registered by the Chinese Clinical Trial Registry., Clinical Trial Registration Number: ChiCTR2000032743., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Sleep deprivation and emotional problems such as stress, anxiety, and depression commonly occur in university students. Exercise is beneficial to ameliorate those problems; however, university students are not serious to take up physical activity. Commercially available exergame such as Xbox ® 360 Kinect is one of the alternatives. This study aims at investigating the feasibility and the potential efficacy of using Xbox 360 Kinect game among health care undergraduate students. A pilot two-armed parallel randomized controlled trial was implemented. A total of 36 undergraduate students was recruited and randomly allocated into the intervention group (playing Xbox 360 Kinect) or the control group (continue with normal daily routine). The intervention group received 30 minutes of Xbox Kinect activity, three times per week for 6 weeks. Information on psychology (Depression, Anxiety, and Stress Scale-21) and sleep (Functional Outcome Sleep Questionnaire-30) status was collected at pre- and post-experiment. The researcher-developed feasibility questionnaire was given to the participants in the intervention group at post-experiment. Repeated-measures analysis of variance was used to investigate within-between group comparison, and significance value was set at p  ≤ 0.05. The analysis found potential improvement on sleep ( p  = 0.039) and psychological health ( p  = 0.002-0.067). The intervention protocol is feasible and highly accepted by the participants. The required optimum amount of dosage, sample size, and the use of outcome measures are suggested from the findings. This pilot and feasibility study supports the use of Xbox 360 Kinect games in practice and to be implemented for future research.

Fatigue and sleep deficiency among public safety personnel are threats to wellness, public and personal safety, and workforce retention. Napping strategies may reduce work-related fatigue, improve safety and health, yet in some public safety organizations it is discouraged or prohibited. Our aim with this commentary is to define intra-shift napping, summarize arguments for and against it, and to outline potential applications of this important fatigue mitigation strategy supported by evidence. We focus our discussion on emergency medical services (EMS); a key component of the public safety system, which is comprised of police, fire, and EMS. The personnel who work in EMS stand to benefit from intra-shift napping due to frequent use of extended duration shifts, a high prevalence of personnel working multiple jobs, and evidence showing that greater than half of EMS personnel report severe fatigue, poor sleep quality, inadequate inter-shift recovery, and excessive daytime sleepiness. The benefits of intra-shift napping include decreased sleepiness and fatigue, improved recovery between shifts, decreased anxiety, and reduced feelings of burnout. Intra-shift napping also mitigates alterations in clinician blood pressure associated with disturbed sleep and shift work. The negative consequences of napping include negative public perception, acute performance deficits stemming from sleep inertia, and the potential costs associated with reduced performance. While there are valid arguments against intra-shift napping, we believe that the available scientific evidence favors it as a key component of fatigue mitigation and workplace wellness. We further believe that these arguments extend beyond EMS to all sectors of public safety., (© 2020 The Authors. American Journal of Industrial Medicine published by Wiley Periodicals LLC.)

Night-workers, transcontinental travelers and individuals that regularly shift their sleep timing, suffer from circadian desynchrony and are at risk to develop metabolic disease, cancer, and mood disorders, among others. Experimental and clinical studies provide evidence that food intake restricted to the normal activity phase is a potent synchronizer for the circadian system and can prevent the detrimental metabolic effects associated with circadian disruption. As an alternative, we hypothesized that a timed piece of chocolate scheduled to the onset of the activity phase may be sufficient stimulus to synchronize circadian rhythms under conditions of shift-work or jet-lag. In Wistar rats, a daily piece of chocolate coupled to the onset of the active phase (breakfast) accelerated re-entrainment in a jet-lag model by setting the activity of the suprachiasmatic nucleus (SCN) to the new cycle. Furthermore, in a rat model of shift-work, a piece of chocolate for breakfast prevented circadian desynchrony, by increasing the amplitude of the day-night c-Fos activation in the SCN. Contrasting, chocolate for dinner prevented re-entrainment in the jet-lag condition and favored circadian desynchrony in the shift-work models. Moreover, chocolate for breakfast resulted in low body weight gain while chocolate for dinner boosted up body weight. Present data evidence the relevance of the timing of a highly caloric and palatable meal for circadian synchrony and metabolic function.

Over a quarter of employees in North America and a fifth of those in the European Union do shift work. Working these schedules increases fatigue, sleepiness, and errors at work. In the long term, it may also increase the risk of cardiovascular disease, gastrointestinal problems, and cancer. Some of these consequences may be partly due to circadian misalignment, in which sleep and activity patterns no longer align with one's circadian rhythms. Previous research has found that controlling light exposure can improve circadian alignment in individuals who work permanent night shifts. However, light-based interventions are rarely tested with rapidly rotating shift schedules, which include more than one type of shift within the same week (e.g., day shifts followed by night shifts). Further, many of the available interventions are seldom used in the workplace and may be less feasible in healthcare environments. In hospitals, the health and safety of both workers and patients can be compromised by increases in fatigue. We thus developed a practical intervention based on circadian and sleep hygiene principles to reduce some of the negative consequences associated with shift work. We then tested this intervention in a feasibility study of 33 nurses working rapidly rotating shifts. The study took place over two separate periods: the control (observation) period and the intervention period. Each period included two to four consecutive night shifts as well as the two days before and after those shifts. Nurses completed daily self-report questionnaires during both periods. During the intervention period, the nurses additionally followed a fatigue reduction plan. The plan involved 40 min of bright light exposure from a portable light box before night shifts, light avoidance using sunglasses after those shifts, and suggestions regarding the ideal times to sleep and nap. Results showed that nurses complied with the large majority of these recommendations. During the intervention period, nurses reported less fatigue, fewer work errors, better and longer sleep, and a more positive mood. Moreover, nurses with a preference for evenings (i.e., later chronotypes) reported the strongest benefits. Though more controlled studies are needed to assess causal mechanisms and long-term effectiveness, these promising results suggest that light-based interventions are feasible and may be effective at reducing fatigue in rapidly rotating shift workers.

Aim: We systematically reviewed the quality of sleep measurement instruments applied to shift-work nurses and analyzed the effects of intervention research., Background: There is a need to test the effects of experimental studies worldwide that conducted interventions to improve the sleep quality of nurses who work shiftwork., Methods: In this systematic literature review and meta-analysis, we used PICO (Participant, Intervention, Comparison, and Outcome) and searched for papers in Korean and English published up until August 2018. We utilized Cochrane Review Manager Software 5.3., Results: Thirteen articles from 1991 to 2018 were included in the systematic literature review, and 6 of those were used in a meta-analysis. The instrument used most often to asses subjective sleep quality was the Pittsburgh Sleep Quality Index. Additionally, an actigraph and sleep logs were used to collect physiological data about participants' sleep quality. Intervention types were categorized into aroma-inhalation therapy, shift-rotation interventions, physical-activity interventions, and cognitive-behavioral therapy. Ultimately, the effects of the aroma-inhalation therapy intervention significantly improved shift-work nurses' sleep quality., Conclusions: We established a basic understanding of a strategy to measure and improve participants' sleep quality. Consequently, sleep interventions that can positively promote nurses' health and foster effective job performance should be developed., Competing Interests: Declaration of competing interest No conflict of interest has been declared by the authors., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Background: Around the age of 6 months, difficulties in settling to sleep and frequent night awakenings are generally occurring in 20 to 30% of infants. According to the transactional model parental factors can play a significant role in influencing infant sleep development. The purpose of the current study was to explore the combined effect of infants' factors (temperament and sleep onset problems), and parental factors (parental mental health in terms of post-partum affective disorders, consistent bedtime routines and fathers' involvement at bedtime), on infant bedtime difficulties (e.g. fussing, crying or protesting), including both maternal and paternal perspectives., Methods: Sixty Italian intact two-parent families of infants (34 boys and 26 girls) ageing from 8 to 12 months (M = 10.73, SD = 2.54) were enrolled in the study. The parents filled out self-report questionnaires to measure the aforementioned variables. To investigate which infant and parental factors predicted infants' bedtime difficulties, two multiple linear regressions (MR), one for fathers and one for mothers, and relative weight analyses (RWA) were conducted., Results: With regard to infants' bedtime difficulties reported by fathers (R 2  = .35) they were explained by infant involvement in constant bedtime routines (β = -.35, p = .030) and paternal involvement at bedtime (β = -.45, p = .007). Instead infants' bedtime difficulties reported by mothers (R 2  = .32) were explained by minutes the child taken to fall asleep (β = .24, p = .04), infant involvement in constant bedtime routines (β = -.31, p = .01) and bedtime paternal involvement (β = -.27, p = .05)., Conclusions: The main results of this study emphasized the protective role of consistent bedtime routines and bedtime paternal involvement in reducing infants' bedtime difficulties perceived both from mothers and fathers. Future research could help to raise awareness and improve understanding of the familial influences on children's sleep, providing recommendations for educating families, school professionals, healthcare providers, and the general public on risk and protective factors that could play a meaningful role in infants and children's developing sleep patterns.

Objective: The aims of this study were: 1) to determine the short-term impact of the SleepTrackTXT2 intervention on air-medical clinician fatigue during work shifts and 2) determine the longer-term impact on sleep quality over 120 days. Methods: We used a multi-site randomized controlled trial study design with a targeted enrollment of 100 (ClinicalTrials.gov NCT02783027). The intervention was behavioral (non-pharmacological) and participation was scheduled for 120 days. Participation was voluntary. All consented participants answered baseline as well as follow-up surveys. All participants answered text message queries, which assessed self-rated fatigue, sleepiness, concentration, recovery, and hours of sleep. Intervention participants received additional text messages with recommendations for behaviors that can mitigate fatigue. Intervention participants received weekly text messages that promoted sleep. Our analysis was guided by the intent-to-treat principle. For the long-term outcome of interest (sleep quality at 120 days), we used a two-sample t-test on the change in sleep quality to determine the intervention effect. Results: Eighty-three individuals were randomized and 2,828 shifts documented (median shifts per participant =37, IQR 23-49). Seventy-one percent of individuals randomized (n = 59) participated up to the 120-day study period and 52% (n = 43) completed the follow-up survey. Of the 69,530 text messages distributed, participants responded to 61,571 (88.6%). Mean sleep quality at 120 days did not differ from baseline for intervention (p > 0.05) or control group participants (p > 0.05), and did not differ between groups (p > 0.05). There was no change from baseline to 120 days in the proportion with poor sleep quality in either group. Intra-shift fatigue increased (worsened) over the course of 12-hour shifts for participants in both study arms. Fatigue at the end of 12-hour shifts was higher among control group participants than participants in the intervention group (p < 0.05). Pre-shift hours of sleep were often less than 7 hours and did not differ between the groups over time. Conclusions: The SleepTrackTXT2 behavioral intervention showed a positive short-term impact on self-rated fatigue during 12-hour shifts, but did not impact longer duration shifts or have a longer-term impact on sleep quality among air-medical EMS clinicians.

Objectives: The primary aims of the present study were to assess the sleep hygiene knowledge of high performance team sport coaches and sports science support staff; the sleep practices these individuals implement with athletes; and the barriers to the more frequent use of these practices., Design: Cross-sectional observational study., Methods: A sample of 86 Australian coaches and sports science support staff working within high performance team sport volunteered to complete a four-part questionnaire, including the Sleep Beliefs Survey used to assess sleep hygiene knowledge., Results: Overall sleep hygiene knowledge was adequate (15.3±2.9, score range 0-20; mean±SD), however knowledge of sleep-wake cycle behaviours (score 4.9±1.6 out of 7) and thoughts and attitudes about sleep (3.6±1.0 out of 5) were inadequate. Over half (56%) of coaches and support staff had monitored athlete sleep, while 43% had promoted sleep hygiene. Lack of resources (response range 44-60%) and knowledge (16-41%) were the two main barriers to the implementation of sleep monitoring and sleep hygiene practices., Conclusions: Team sport coaches and sports science support staff have adequate overall sleep hygiene knowledge, yet some specific areas (e.g. sleep-wake cycle behaviours) warrant improvement. There appear to be limited sleep practices implemented with athletes, particularly regarding the promotion of sleep hygiene. The development of educational sleep resources for coaches and support staff to implement with athletes may help address the identified barriers and improve sleep knowledge., (Copyright © 2019 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.)

Canada's freight rail system moves 70% of the country's surface goods and almost half of all exports (RAC, 2016). These include dangerous goods. Anonymous survey of freight rail operating employees conducted by the Teamsters Canada Rail Conference (TCRC, 2014) revealed that many do not report getting enough sleep because of their work schedules, and that fatigue may be affecting their performance at work. Besides general impairments in attention and cognitive functioning, fatigue in railway operating employees slows reaction time to safety alarms and impairs conformance to train operating requirements. Shift scheduling practices can contribute to sleep-related fatigue by restricting sleep opportunities, requiring extended periods of wakefulness and by disrupting daily (circadian) rhythms. The primary goal of accident investigation is to identify causal and contributing factors so that similar occurrences can be prevented. A database search of Transportation Safety Board (TSB) rail investigation reports published in the 21-year period from 1995 to 2015 identified 18 that cited sleep-related fatigue of freight rail operating employees as a causal, contributing, or risk finding. This number represents about 20% of TSB rail investigations from the same period in which a human factors aspect of freight train activities was a primary cause. Exploration of accident themes suggests that management of fatigue and shift scheduling in the freight rail industry is a complex issue that is often not conducive to employee circadian rhythms and sleep requirements. It also suggests that current shift scheduling and fatigue management practices may be insufficient to mitigate the associated safety risk. Railway fatigue management systems that are based on the principles of modern sleep science are needed to improve scheduling practices and mitigate the ongoing safety risk., (Crown Copyright © 2018. Published by Elsevier Ltd. All rights reserved.)

A substantial body of literature indicates that shift workers have a significantly higher risk of workplace accidents and injuries, compared to workers in regular daytime schedules. This can be attributed to work during nights which require workers to stay awake during normal sleeping hours and sleep during natural waking hours, leading to circadian desynchronization, sleep disruption and cognitive impairment. A fatigue-risk trajectory model developed by Dawson and McCulloch has been used to describe the series of events which may precede fatigue-related incidents. This includes insufficient sleep opportunities, impaired sleep, fatigue-behavioral symptoms, and fatigue-related errors. The purpose of this paper is to provide examples of control measures along each level of the fatigue-risk trajectory, which include: (i) work scheduling strategies to include breaks for adequate sleep opportunities; (ii) training and educational programs to help workers make best use of recovery times for quality sleep; (iii) fatigue-detection devices to alert workers and safety managers of fatigue-related behaviors and errors. A brief introduction to Fatigue-Risk Management systems is also included as a long-term sustainable strategy to maintain shift worker health and safety. The key statements in this paper represent a consensus among the Working Time Society regarding a multi-level approach to managing occupational sleep-related fatigue.

Aim: To identify if complementary interventions impacted on conscious intensive care patients' perception of stress factors and quality of sleep., Research Methodology: A non-controlled clinical study was undertaken on conscious patients in an intensive care unit in central Italy. Patients perception of stress factors and quality of sleep during the first night with usual medical and nursing treatments was measured using two questionnaires: the Stress Factors in Intensive Care Unit Questionnaire and the Modified Richards-Campbell Sleep Questionnaire. During the second night two specific treatments were administered: (1) receptive musical sounds and (2) a massage using sweet lavender/lemon-scented almond oil. The same variables were measured on the third day using the same questionnaires., Results: The data of 74 patients were analysed. The patients' main concerns were "hearing unusual noises" (n = 46, 62.2%), "having people continuously working around the bed" (n = 53, 71.6%), "being worried" (n = 60, 81.1%) and "being unable to sleep" (n = 47, 63.5%). Fifty-three patients (71.6%) reported waking up in the middle of the night and 21 (28.3%) of them were unable to fall asleep again. Receptive musical sounds and massage using aromatherapy improved the quality of patients' sleep (t = 2.01, p = 0.047)., Conclusion: Complementary interventions may reduce patients' perception of stress and improve their sleep. Further research is now needed., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Introduction: Shift patterns, work hours, work arrangements and worker motivations have increasingly become key factors for job performance. The main objective of this article is to design an expert system that identifies the negative effects of shift work and prioritizes mitigation efforts according to their importance in preventing these negative effects. The proposed expert system will be referred to as the shift expert., Methods: A thorough literature review is conducted to determine the effects of shift work on workers. Our work indicates that shift work is linked to demographic variables, sleepiness and fatigue, health and well-being, and social and domestic conditions. These parameters constitute the sections of a questionnaire designed to focus on 26 important issues related to shift work. The shift expert is then constructed to provide prevention advice at the individual and organizational levels, and it prioritizes this advice using a fuzzy analytic hierarchy process model, which considers comparison matrices provided by users during the prioritization process. An empirical study of 61 workers working on three rotating shifts is performed. After administering the questionnaires, the collected data are analyzed statistically, and then the shift expert produces individual and organizational recommendations for these workers.

Night work is not only a work performed at night. It has also to be considered as a specifically organized work with its own duties and moving tasks in a different relational context. Primary preventive assessments regarding work schedules and occupational associated constraints have to be considered beside family potential consequences. Taking account of the consensually accepted impact of night-shift work on health, particularly on sleep, we recommend an annual medical visit for night-shift workers. We also recommend to declare the night shift diseases to the Regional committee of occupational diseases via the "alinea 4"., (Copyright © 2018 Elsevier Masson SAS. All rights reserved.)

Objectives: We reviewed Jetlag, particularly in view of its effects on sleep and how it can be managed., Methods: The Proquest Central database of Kırıkkale University, PubMed and Google scholar were used while searching for the following key words: "Jetlag", "symptoms", "sleep", "melatonin" and "treatment"., Results: Flight dysrhythmia, otherwise known as jetlag, is caused by flying globally over various time zones. Most passengers who fly over six or more different time zones generally require 4-6 days after travelling to resume their usual sleep patterns and to feel less lethargic during the day. Signs of jet lag can vary between debilitated awareness, insomnia, feeling tired during the day and frequent waking during the night. During the night our pineal glands excrete a hormone called melatonin; dim lights cause the continuation of excretion of these hormones whereas any exposure to bright lights stems the flow of release. Common precautionary measures are specific diets, bright lights and melatonin agonists (Ramelteon, Agomelatine)., Conclusion: Sleep issues derived from jetlag were found to be most common in passengers who flew through various time belts. Melatonin assumes a critical part in adjusting the body's circadian rhythms and has been utilized restoratively to re-establish irritated circadian rhythms., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Background: Shift work disorder (SWD) is a major concern for both healthcare workers (HCWs) employed in hospital wards and healthcare organizations. The consequences of SWD may lead to increased service costs and lower standards of care., Objectives: To identify and evaluate the latest developments in assessing and managing the occupational risk of SWD in shift-HCWs through a search of the literature published in the last five years., Methods: We performed a search of the literature starting from June 2012, using MEDLINE/Pubmed. The articles were reviewed and categorized into one or more of the following categories based on their subject matter: Risk assessment, Risk management, Occurrence rates., Results: A total of 25 publications matched the inclusion criteria. The topics discussed, in order of frequency (from the highest to the lowest), were: "Risk Assessment" (84%), "Occurrence Rates" (64%) and "Risk Management" (48%). Number of nights worked per year, long night-time working hours, frequent missing of nap opportunities during night-shift, quick returns and unhealthy workplace were found as organizational determinants of SWD that should be prioritized in the risk assessment of shift work in the healthcare sector., Conclusions: Organizational interventions targeted on both healthy shift-work scheduling and improvement of the workplace safety are proposed to moderate the occurrence of SWD and, consequently, to ensure HCWs' wellness and suitable standards of patient care. Further studies aimed to investigate the effectiveness of such interventions in minimizing SWD occurrence are needed.

Background: Fatigue training may be an effective way to mitigate fatigue-related risk. We aimed to critically review and synthesize existing literature on the impact of fatigue training on fatigue-related outcomes for Emergency Medical Services (EMS) personnel and similar shift worker groups., Methods: We performed a systematic literature review for studies that tested the impact of fatigue training of EMS personnel or similar shift workers. Outcomes of interest included personnel safety, patient safety, personnel performance, acute fatigue, indicators of sleep duration and quality, indicators of long-term health (e.g., cardiovascular disease), and burnout/stress. A meta-analysis was performed to determine the impact of fatigue training on sleep quality., Results: Of the 3,817 records initially identified for review, 18 studies were relevant and examined fatigue training in shift workers using an experimental or quasi-experimental design. Fatigue training improved patient safety, personal safety, and ratings of acute fatigue and reduced stress and burnout. A meta-analysis of five studies showed improvement in sleep quality (Fixed Effects SMD -0.87; 95% CI -1.05 to -0.69; p < 0.00001; Random Effects SMD -0.80; 95% CI -1.72, 0.12; p < 0.00001)., Conclusions: Reviewed literature indicated that fatigue training improved safety and health outcomes in shift workers. Further research is required to identify the optimal components of fatigue training programs to maximize the beneficial outcomes.

Objectives: Night workers often experience high levels of sleepiness due to misalignment of the sleep-wake cycle from the circadian pacemaker, in addition to acute and chronic sleep loss. Exposure to light, in particular short wavelength light, can improve alertness and neurobehavioural performance. This randomised controlled trial examined the efficacy of blue-enriched polychromatic light to improve alertness and neurobehavioural performance in night workers., Design: Participants were 71 night shift workers (42 males; 32.8±10.5 years) who worked at least 6 hours between 22:00 and 08:00 hours. Sleep-wake logs and wrist actigraphy were collected for 1-3 weeks, followed by 48-hour urine collection to measure the circadian 6-sulphatoxymelatonin (aMT6s) rhythm. On the night following at least two consecutive night shifts, workers attended a simulated night shift in the laboratory which included subjective and objective assessments of sleepiness and performance. Workers were randomly assigned for exposure to one of two treatment conditions from 23:00 hours to 07:00 hours: blue-enriched white light (17 000 K, 89 lux; n=36) or standard white light (4000 K, 84 lux; n=35)., Results: Subjective and objective sleepiness increased during the night shift in both light conditions (p<0.05, η p 2 =0.06-0.31), but no significant effects of light condition were observed. The 17 000 K light, however, did improve subjective sleepiness relative to the 4000 K condition when light exposure coincided with the time of the aMT6s peak (p<0.05, d=0.41-0.60)., Conclusion: This study suggests that, while blue-enriched light has potential to improve subjective sleepiness in night shift workers, further research is needed in the selection of light properties to maximise the benefits., Trial Registration Number: The Australian New Zealand Clinical Trials Registry ACTRN12610000097044 (https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=320845&isReview=true)., Competing Interests: Competing interests: TLS reports that her institution has received equipment donations or other support from Philips Lighting, Philips Respironics, Optalert and Compumedics. She serves as a Project Leader in the Cooperative Research Centre for Alertness, Safety and Productivity. SFt serves as a Project Leader in the Cooperative Research Centre for Alertness, Safety and Productivity. RRG serves as a Program Leader in the Cooperative Research Centre for Alertness, Safety and Productivity which provides equipment and other in-kind support for research from Philips. In the past 5 years, SWL has received consulting fees from Blackrock, Carbon Limiting Technologies (on behalf of PhotonStar LED), Cowen & Co, Endurant Capital Management, Far West Capital Management, Fidelity, Frankel Group, Impax Laboratories, Kearney Venture Partners, Lazard Capital Markets, Naturebright, New Horizon Capital, Perceptive Advisors, Polar Capital, ResearchWorks, Serrado Capital, Thomas Jefferson University and Wyvern Funds; has current consulting contracts with Akili Interactive, Delos Living LLC, Environmental Light Sciences LLC, Focal Point LLC, Headwaters, Hintsa Performance AG, OpTerra Energy Services, Pegasus Capital Advisors LP, PlanLED, Wyle Integrated Science and Engineering; has received unrestricted equipment gifts from Bioilluminations LLC, Bionetics Corporation and Philips Lighting; a fellowship gift from Optalert; advance author payment and royalties from Oxford University Press; payment for editing a textbook section from Elsevier; honoraria from the National Sleep Foundation and for an article in the Wall Street Journal; honoraria plus travel, accommodation or meals for invited seminars, conference presentations or teaching from Brookline Adult Education, Brown University, Estee Lauder, Harvard University (CME), MediCom Worldwide (CME); travel, accommodation and/or meals only (no honoraria) for invited seminars, conference presentations or teaching from the 8th International Conference on Managing Fatigue, 14th Annual Tennessee Perfusion Conference, American Society for Photobiology, Cantifix, Connecticut Business & Industry Association Health and Safety Conference, Emergency Services Steering Committee, FASEB, Harvard University, Hintsa Performance AG, Illuminating Engineering Society, Lightfair, Massachusetts General Hospital, Midwest Lighting Institute, New England College of Occupational and Environmental Medicine, Ontario Association of Fire Chiefs, Rio Tinto, UMass Memorial, University of Manchester, University of Texas Medical Branch and Woolcock Institute of Medical Research; ongoing investigator-initiated research grants from Biological Illuminations LLC and Respironics; completed service agreements with Rio Tinto Iron Ore and Vanda Pharmaceuticals; three completed sponsor-initiated clinical research contracts with Vanda Pharmaceuticals; and one completed investigator-initiated research grant from Vanda Pharmaceuticals. SWL also holds a process patent for the use of short-wavelength light for resetting the human circadian pacemaker and improving alertness and performance which is assigned to the Brigham and Women’s Hospital per hospital policy and has received revenue from a patent on the use of short-wavelength light, which is assigned to the University of Surrey. SWL has also served as a paid expert witness on behalf of eight public bodies and one union for arbitration and cases related to sleep, circadian rhythms and work hours. SWL also serves as a Program Leader in the Cooperative Research Centre for Alertness, Safety and Productivity. SMWR reports that he has served as a consultant through his institution to Vanda Pharmaceuticals, Philips Respironics, EdanSafe, The Australian Workers’ Union, National Transport Commission and Transport Accident Commission and has through his institution received research grants and/or unrestricted educational grants from Vanda Pharmaceuticals, Takeda Pharmaceuticals North America, Philips Lighting, Philips Respironics, Cephalon and ResMed Foundation and reimbursements for conference travel expenses from Vanda Pharmaceuticals. His institution has received equipment donations or other support from Optalert, Compumedics and Tyco Healthcare. He has also served as an expert witness and/or consultant to shift work organisations. SMWR also serves as a Program Leader in the Cooperative Research Centre for Alertness, Safety and Productivity., (© Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.)

Shift work sleep disorder is a common problem in industrialized countries because of the need for occupations and services to continue to function 24 hours/day. Approximately 20% of employed adults in the United States are engaged in shift work. Shift work sleep disorder is diagnosed if there is a report of insomnia or excessive sleepiness for at least 3 months associated with a recurring work schedule that overlaps the usual time for sleep. Shift work is associated with an increased occurrence of metabolic disorders, such as insulin resistance, diabetes, dyslipidemia, and metabolic syndrome, and it has been implicated in weight gain and cognitive impairment. There is evidence of increased absenteeism in night workers compared with day workers. A planned sleep schedule, timed bright light exposure, timed melatonin administration, and stimulants or drugs promoting alertness can be used to manage shift work sleep disorder. Jet lag is characterized by a misalignment between internal circadian rhythms and local time caused by rapid travel across at least two time zones. Not all travelers experience jet lag; risk factors include age, number of time zones crossed, and circadian preference. Management includes timed melatonin along with optional timed and dosed bright light exposure., (Written permission from the American Academy of Family Physicians is required for reproduction of this material in whole or in part in any form or medium.)

Objectives: Napping has known benefits for fatigue mitigation and improved alertness. However the Accreditation Council for Graduate Medical Education (ACGME) New Common Program Requirements recently removed the 16 h work limit for PGY1 residents and removed any suggestions of napping., Methods: We utilized a cross-sectional study design to administer a 44-item questionnaire in June 2016 to 858 residents and fellows at one large urban academic medical center. We assessed: 1) resident physician sentiment of work environment supportiveness for napping at work; and 2) agreement with 2011 ACGME guidelines on workweek hour limitations and strategic napping recommendations., Results: While 89% of residents reported access to an on-call room at work, only 20% felt their work environment supported a culture of napping while at work. Over 76% expressed agreement with the 2011 ACGME work-hour restrictions., Conclusions: Strategies to support napping and well-being within the resident physician workforce and organizational setting are warranted., (© 2017 Wiley Periodicals, Inc.)

Background: Most air medical Emergency Medical Services (EMS) clinicians work extended duration shifts, and more than 50% report inadequate sleep, poor sleep quality, and/or poor recovery between shifts. The SleepTrackTXT pilot trial (ClinicalTrials.gov, NCT02063737) showed that use of mobile phone text messages could impact EMS clinician self-reported fatigue and sleepiness during long duration shifts. The purpose of the SleepTrackTXT2 trial is to leverage lessons learned from the first SleepTrackTXT study and test an enhanced intervention targeting air medical EMS clinicians., Methods/design: We will conduct a multi-site randomized trial with a sample of adult EMS clinicians recruited from four air medical EMS systems located in the midwest, northeastern, and southern USA. Participants will be allocated to one of two possible arms for a 4-month (120-day) study period. The intervention arm will involve text-message assessments of sleepiness, fatigue, and difficulty concentrating at the beginning, every 4 hours during, and at the end of scheduled shifts. Participants reporting high levels of sleepiness, fatigue, or difficulty with concentration will receive one of nine randomly selected intervention messages to promote behavior change during shift work to improve alertness. Intervention participants will receive a text-message report on Friday of each week that shows their sleep debt over the previous 7 days followed by a text message to promote paying back sleep debt recovery when feasible. Participants in the control group receive text messages that only include assessments. Both arms will receive text-message assessments of perceived recovery since last shift, sleepiness, fatigue, or difficulty with concentration at noon (1200 hours) on days between scheduled shifts (off-duty days). We have two aims for this study: (1) to determine the short-term impact of the enhanced SleepTrackTXT2 intervention on air medical clinician fatigue reported in real time during and at the end of shift work, and (2) to determine the long-term impact of the SleepTrackTXT2 intervention on sleep quality and sleep health indicators including hours of sleep and recovery between shift work., Discussion: The SleepTrackTXT2 trial may provide evidence of real-world effectiveness that would support widespread expansion of fatigue mitigation interventions in emergency care clinician shift workers. The trial may specifically support use of real-time assessments and interventions delivered via mobile technology such as text messaging., Trial Registration: ClinicalTrials.gov, NCT02783027 . Registered on 23 May 2016.

A significant proportion of the labor force works irregular hours during harvest, summer, or holiday work surges. Unfortunately such workers are often uninformed about the importance of sleep and fatigue management. Seasonally timed worker training can improve health and safety outcomes during work surges., (© 2015 The Author(s).)

Objectives: The aim of this review was to identify which limited wake shift work schedules (LWSW) best promote sleep, alertness, and performance. LWSW are fixed work/rest cycles where the time-at-work does is ≤8 hours and there is >1 rest period per day, on average, for ≥2 consecutive days. These schedules are commonly used in safety-critical industries such as transport and maritime industries., Methods: Literature was sourced using PubMed, Embase, PsycInfo, Scopus, and Google Scholar databases. We identified 20 independent studies (plus a further 2 overlapping studies), including 5 laboratory and 17 field-based studies focused on maritime watch keepers, ship bridge officers, and long-haul train drivers. The measurement of outcome measures was varied, incorporating subjective and objective measures of sleep: sleep diaries (N=5), actigraphy (N=4), and polysomnography, (N=3); sleepiness: Karolinska Sleepiness Scale (N=5), visual analog scale (VAS) alertness (N=2) and author-derived measures (N=2); and performance: Psychomotor Vigilance Test (PVT) (N=5), Reaction Time or Vigilance tasks (N=4), Vector and Letter Cancellation Test (N=1), and subjective performance (N=2)., Results: Of the three primary rosters examined (6 hours-on/6 hours-off, 8 hours-on/8 hours-off and 4 hours-on/8 hours-off), the 4 hours-on/8 hours-off roster was associated with better sleep and lower levels of sleepiness. Individuals working 4 hours-on/8 hours-off rosters averaged 1 hour more sleep per night than those working 6 hours-on/6 hours-off and 1.3 hours more sleep than those working 8 hours-on/8 hours-off (P<0.01). More broadly, findings indicate that LWSW schedules were associated with better sleep and lower sleepines in the case of (i) shorter time-at-work, (ii) more frequent rest breaks, (iii) shifts that start and end at the same clock time every 24 hours, and (iv) work shifts commencing in the daytime (as opposed to night). The findings for performance remain incomplete due to the small number of studies containing a performance measure and the heterogeneity of performance measures within those that did., Conclusion: The literature supports the utility of LWSW in industries where individuals sleep at or near the workplace as they facilitate at least some sleep during the biological night and minimize deficits associated with time-on-shift with shorter shifts. Overall, the 4 hour-on/8 hour-off roster best promoted sleep and minimized sleepiness compared to other LWSW schedules. Nevertheless, and considering the safety-critical nature of industries which employ LWSW, the limited literature needs to be greatly expanded with specific focus on the consequences for performance and comparison to mainstream rosters.

Background: There are conflicting reports regarding seasonal sleep difficulties in polar regions. Herein we report differences in actigraphic sleep measures between two summer trials (collected at Canadian Forces Station Alert, 82.5°N, in 2012 and 2014) and evaluate exogenous melatonin for preventing/treating circadian phase delay due to nocturnal light exposure., Methods: Subjects wore actigraphs continuously to obtain sleep data. Following seven days of actigraphic recording the subjects filled out questionnaires regarding sleep difficulty and psychosocial parameters and subsequently remained in dim light conditions for 24 hours, during which saliva was collected bihourly to measure melatonin. During Trial 2, individuals who reported difficulty sleeping were prescribed melatonin, and a second saliva collection was conducted to evaluate the effect of melatonin on the circadian system., Results: Trial 1 subjects collectively had late dim light melatonin onsets and difficulty sleeping; however, the Trial 2 subjects had normally timed melatonin rhythms, and obtained a good quantity of high-quality sleep. Nocturnal light exposure was significantly different between the trials, with Trial 1 subjects exposed to significantly more light between 2200 and 0200h. Melatonin treatment during Trial 2 led to an improvement in the subjective sleep difficulty between the pre- and post-treatment surveys; however there were no significant differences in the objective measures of sleep., Conclusions: The difference in sleep and melatonin rhythms between research participants in June 2012 and June 2014 is attributed to the higher levels of nocturnal light exposure in 2012. The avoidance of nocturnal light is likely to improve sleep during the Arctic summer., (Crown Copyright © 2014. Published by Elsevier B.V. All rights reserved.)

Now that the 24-hour economy is putting an ever-increasing mark on social life, the effects of the disruption of natural biological rhythms are becoming clearer. In addition to its effects on sleep, this article discusses its long-term health effects. Potential measures to reduce and counteract the adverse effects of working night shifts on general well-being, sleep and health are summarized; the roles of light and rhythm are explored. Further research into the health effects of working nights and unsociable shift patterns is indicated.

Objectives: The aim of this study was to evaluate the effects of an mHealth intervention (intervention using mobile technology) consisting of tailored advice regarding exposure to daylight, sleep, physical activity, and nutrition, and aiming to improve health-related behavior, thereby reducing sleep problems and fatigue and improving health perception of airline pilots., Methods: A randomized controlled trial was conducted among 502 airline pilots. The intervention group was given access to both the MORE Energy mobile application (app) with tailored advice and a website with background information. The control group was directed to a website with standard information about fatigue. Health-related behavior, fatigue, sleep, and health perception outcomes were measured through online questionnaires at baseline and at three and six months after baseline. The effectiveness of the intervention was determined using linear and Poisson mixed model analyses., Results: After six months, compared to the control group, the intervention group showed a significant improvement on fatigue (β= -3.76, P<0.001), sleep quality (β= -0.59, P=0.007), strenuous physical activity (β=0.17, P=0.028), and snacking behavior (β= -0.81, P<0.001). No significant effects were found for other outcome measures., Conclusions: The MORE Energy mHealth intervention reduced self-reported fatigue compared to a minimal intervention. Some aspects of health-related behavior (physical activity and snacking behavior) and sleep (sleep quality) improved as well, but most did not. The results show offering tailored advice through an mHealth intervention is an effective means to support employees who have to cope with irregular flight schedules and circadian disruption. This kind of intervention might therefore also be beneficial for other working populations with irregular working hours.

Objectives: Associations between shift work and chronic disease have been observed, but relatively little is known about how to mitigate these adverse health effects. This critical review aimed to (i) synthesize interventions that have been implemented among shift workers to reduce the chronic health effects of shift work and (ii) provide an overall evaluation of study quality., Methods: MeSH terms and keywords were created and used to conduct a rigorous search of MEDLINE, CINAHL, and EMBASE for studies published on or before 13 August 2012. Study quality was assessed using a checklist adapted from Downs & Black., Results: Of the 5053 articles retrieved, 44 met the inclusion and exclusion criteria. Over 2354 male and female rotating and permanent night shift workers were included, mostly from the manufacturing, healthcare, and public safety industries. Studies were grouped into four intervention types: (i) shift schedule; (ii) controlled light exposure; (iii) behavioral; and, (iv) pharmacological. Results generally support the benefits of fast-forward rotating shifts; simultaneous use of timed bright light and light-blocking glasses; and physical activity, healthy diet, and health promotion. Mixed results were observed for hypnotics. Study quality varied and numerous deficiencies were identified., Conclusions: Except for hypnotics, several types of interventions reviewed had positive overall effects on chronic disease outcomes. There was substantial heterogeneity among studies with respect to study sample, interventions, and outcomes. There is a need for further high-quality, workplace-based prevention research conducted among shift workers.

Disruption in police officers. In recent years there has been a widespread growth in services, available regardless of time or day organization (24/7 service) and a diffuse increase in their use, both in work and private lives, generally ignoring the importance of a regular sleep organization. Police officers - often need to work extended shifts and long hours under highly stressful conditions, which results in reduced levels of safety and operational effectiveness. In numerous studies, perceived stress has been found to correlate with both subjective and objective disturbances in sleep. Consequently, excessive daytime sleepiness is one of the most frequent health and safety hazards that police officers have to deal with. Sleep deprivation affects performance outcomes through a wide range of cognitive domains. Sleepiness and fatigue, caused by sleep loss, extended work and wakefulness, circadian misalignment and sleep disorders are major causes of workplace human errors, incidents, and accidents. Therefore, prevention of sleep loss, high levels of stress and fatigue is a key factor to consider when assessing emergency intervention. In order to combat fatigue and sleepiness, a 30-90 minutes nap before night shift could be a viable option.

Almost all forms of life have predictable daily or circadian rhythms in molecular, endocrine, and behavioral functions. In mammals, a central pacemaker located in the suprachiasmatic nuclei coordinates the timing of these rhythms. Daily light exposure that affects the retina of the eye directly influences this area, which is required to align endogenous processes to the appropriate time of day. The present "Views and Reviews" articles discuss the influence of circadian rhythms, especially nightly secretion of melatonin, on reproductive function and parturition. In addition, an examination is made of problems that arise from recurrent circadian rhythm disruption associated with changes in light exposure patterns common to modern day society. Finally, a possible solution to prevent disruptions in circadian phase markers by filtering out short wavelengths from nocturnal light is reviewed., (Copyright © 2014 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.)

Shiftwork has been identified as a risk factor for various medical problems, such as cancer, heart disease, metabolic disturbances, depression, and anxiety disorders, and as reviewed this month, adverse reproductive function. Shiftwork misaligns physiological rhythms with respect to each other and to external environmental rhythms such as the 24-hour light/dark cycle. Light is the strongest time cue for entraining circadian rhythms in mammals, and aberrant light exposure patterns during shiftwork is one of the key factors that induce circadian misalignment. We have recently demonstrated, in both animal and clinical models, that filtering short wavelengths (below 480 nm) from nocturnal lighting can attenuate alterations in hormone secretion (melatonin and glucocorticoids) and in central and peripheral clock gene expression induced by nighttime light exposure. We also demonstrated that the use of optical filters led to an improvement in mood and in cognitive performance under controlled laboratory conditions and during field-based shiftwork studies. Moreover, there was an increase in sleep duration and quality on nights immediately following night shifts. We believe it is likely that optical filters incorporated into glasses or as coverings for light bulbs could be used as a method to improve or prevent many of the medical problems associated with circadian misalignment and rotating shiftwork., (Copyright © 2014 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.)

Maintaining a stable and adequate sleeping pattern is associated with good health and disease prevention. As a restorative process, sleep is important for supporting immune function and aiding the body in healing and recovery. Aging is associated with characteristic changes to sleep quantity and quality, which make it more difficult to adjust sleep-wake rhythms to changing environmental conditions. Sleep disturbance and abnormal sleep-wake cycles are commonly reported in seriously ill older patients in the intensive care unit (ICU). A combination of intrinsic and extrinsic factors appears to contribute to these disruptions. Little is known regarding the effect that sleep disturbance has on health status in the oldest of old (80+), a group, who with diminishing physiological reserve and increasing prevalence of frailty, is at a greater risk of adverse health outcomes, such as cognitive decline and mortality. Here we review how sleep is altered in the ICU, with particular attention to older patients, especially those aged ≥80 years. Further work is required to understand what impact sleep disturbance has on frailty levels and poor outcomes in older critically ill patients.