Assessment and management of sleep disorders in shift workers: Challenges and considerations for general practice.

BACKGROUND: Shift work is characterised by displaced sleep opportunities and associated sleep disturbance. Shift workers often report sleepiness and other wake time symptoms associated with poor sleep. However, clinical sleep disorders are also prevalent in shift workers. Although prevalence rates are similar or higher in shift workers compared with the general population, help seeking in shift workers with sleep disorders is low. OBJECTIVE: This article aims to provide general practitioners with a contemporary overview of the prevalence rates for sleep disorders in shift workers, to clarify the existing evidence relating to mental and physical health consequences of sleep disorders in shift workers and to highlight the need to consider undiagnosed sleep disorders before attributing sleep-related symptoms solely to work schedules. DISCUSSION: Symptoms of sleep loss associated with shift work overlap with symptoms experienced by individuals living with sleep disorders. Although >40% of middle-aged Australians live with a sleep disorder that requires investigation and management, symptoms in shift workers are often attributed to the work schedule and, as a result, might not be investigated for appropriate diagnosis and treatment. We argue that screening for sleep disorders in shift workers with sleep complaints should be a priority.

Assessment of retinal and choroidal microvasculature in night shift medical workers by OCT angiography.

This study evaluated retinal and choroidal microvascular changes in night shift medical workers and its correlation with melatonin level. Night shift medical workers (group A, 25 workers) and non-night shift workers (group B, 25 workers) were recruited. The images of macula and optic nerve head were obtained by swept-source OCT-angiography. Vessel density of retina, choriocapillaris (CC), choriocapillaris flow deficit (CC FD), choroidal thickness (CT) and choroidal vascularity index (CVI) were measured. 6-sulfatoxymelatonin concentration was analyzed from the morning urine. CC FD and CVI were significantly decreased and CT was significantly increased in group A (all P < 0.05). 6-sulfatoxymelatonin concentration was significantly lower in group A (P < 0.05), which was significantly positively correlated with CC FD size (r = 0.318, P = 0.024) and CVI of the most regions (maximum r-value was 0.482, P < 0.001), and was significantly negatively associated with CT of all regions (maximum r-value was - 0.477, P < 0.001). In night shift medical workers, the reduction of melatonin was significantly correlated with CT thickening, CVI reduction and CC FD reduction, which suggested that they might have a higher risk of eye diseases. CC FD could be a sensitive and accurate indicator to reflect CC perfusion.

Cohort Studies Versus Case-Control Studies on Night-Shift Work and Cancer Risk: The Importance of Exposure Assessment.

It is a general assumption that the prospective cohort study design is the gold standard approach and is superior to the case-control study design in epidemiology. However, there may be exceptions if the exposure is complex and requires collection of detailed information on many different aspects. Night-shift work, which impairs circadian rhythms, is an example of such a complex occupational exposure and may increase the risks of breast, prostate, and colorectal cancer. So far, for logistical reasons, investigators in cohort studies have assessed shift work rather crudely, lacking information on full occupational history and relevant shift-work metrics, and have presented mostly null findings. On the other hand, most cancer case-control studies have assessed the lifetime occupational histories of participants, including collection of detailed night-shift work metrics (e.g., type, duration, intensity), and tend to show positive associations. In this commentary, we debate why cohort studies with weak exposure assessment and other limitations might not necessarily be the preferred or less biased approach in assessing the carcinogenicity of night-shift work. Furthermore, we propose that risk-of-bias assessment and comparison of associations between studies with low versus high risks of bias be considered in future synthesis of the evidence.

Preliminary assessment of rotating shiftwork risk in a 24-hours metal industry.

BACKGROUND: Rotational shiftwork (RS) has been linked to increased risk for safety and health of shift workers, globally. A growing literature has revealed a trend toward increased accident and injury rates in shift workers than non-shift workers. AIMS: The present research was aimed: 1) to develop a methodological path for a preliminary objective assessment of occupational risk by RS in a metal industry 2) to detect the consequent effective interventions for moderating the RS risk. METHODS: A modified version of the Rotational Shiftwork Questionnaire was designed by a panel of experts, through a Delphi study; the questionnaire was used for a pilot study to assess the RS risk in a metal industry. RESULTS: The questionnaire was entitled Rotating Shiftwork Questionnaire-Industry (RSQ-I) and was made up of two sections: 1) Sentinel Events; 2) Risk Factors. The assessment of RS risk showed a medium level of risk in the studied metal industry. Organizational level interventions were detected for moderating the impact of RS-risk on workers' safety and health. CONCLUSION: RSQ-I showed a valid and reliable tool to analyze RS risk in a 24-hours metal industry. The pilot study demonstrated the effectiveness and feasibility of the introduced RSQ-I to approach the risk, through the analysis of both sentinel events and shift schedules.

Night Shift Work and Risk of Breast Cancer in Women.

BACKGROUND: Night shift work involving circadian disruption has been associated with increased breast cancer rates in some epidemiological studies, but the evidence is still on debate. AIM OF THE STUDY: The objective of this study is to assess the association between night shift work and breast cancer in Mexican women. METHODS: A Case-control study was conducted with incident cases of breast cancer at the Instituto de Seguridad Social del Estado de México y Municipios. Cases were interviewed about past exposures prior to the final diagnosis. Controls were women without breast cancer matched on multiple sociodemographic characteristics. RESULTS: 101 cases and 101 matched controls were interviewed; this small sample size provided consistent, but wide estimates of the assessed associations. The multivariate conditional logistic regression showed that breast-feeding was associated with reduced risk for breast cancer (OR 0.12; 95% CI: 0.02-0.60); women who experienced early menarche (12 years) were more likely to develop breast cancer (OR 18.58; 95% CI 18: 2.19-148). Women who worked at night were more likely to develop breast cancer compared to women who never did (OR = 8.58; 95% CI: 2.19-33.8). CONCLUSIONS: Our results are consistent with studies from other countries, which positively associated night shift work with breast cancer.

Working Time Society consensus statements: Evidence-based effects of shift work and non-standard working hours on workers, family and community.

Working time arrangements that require shift work or other non-standard working hours have significant potential to encroach on time that is highly valued for family, social and leisure activity. This can often result in workers experiencing poorer work-family or work-life balance. Based on an extensive literature search and expert knowledge, primary risk factors were identified including shift work; long, irregular and unpredictable working hours; and work on evenings and weekends (in combination and independent of shift work). On the other hand, flexibility, in the form of adequate worker control over work schedules, may be a protective factor. In addition, workers experiencing excessive work-life conflict are likely to reduce their working hours, reflecting a reciprocal relationship between working hours and work-life balance. Workers' families are also affected by shift work and non-standard working hours. Parents' shift work is associated with poorer emotional and developmental outcomes for their children, and to a greater likelihood of risky behavior in adolescence. Additionally, the risk of separation or divorce is increased, especially for parents working night shifts. Due to relationships such as those above, the consequences of shiftwork and non-standard working hours on family and social life are largely dependent on a complex interaction between specific work schedules, other aspects of work organization, and family and individual worker characteristics. This article provides an overview of current evidence regarding the relationships between working time arrangements and various social and family variables, and concludes with shift scheduling and intervention recommendations to improve work-life balance and social well-being.

Association between 12-hr shifts and nursing resource use in an acute hospital: Longitudinal study.

AIM: To evaluate whether ≥12-hr shifts are associated with a decrease in resource use, in terms of care hours per patient day and staffing costs per patient day. BACKGROUND: Nurses working long shifts may become less productive and no research has investigated whether potential cost savings are realized. METHOD: A retrospective longitudinal study using routinely collected data from 32 wards within an English hospital across 3 years (1 April 2012-31 March 2015). There were 24,005 ward-days. Hierarchical linear mixed models measured the association between the proportion of ≥12-hr shifts worked on a ward-day, care hours per patient day and staffing costs per patient day. RESULTS: Compared with days with no ≥12-hr shifts, days with between 50% and 75% ≥12-hr shifts had more care hours per patient day and higher costs (estimate for care hours per patient day: 0.32; 95% CI: 0.28-0.36; estimate for staffing costs per patient day: £8.86; 95% CI: 7.59-10.12). CONCLUSIONS: We did not find reductions in total care hours and costs associated with the use of ≥12-hr shifts. The reason why mixed shift patterns are associated with increased cost needs further exploration. IMPLICATIONS FOR NURSING MANAGEMENT: Increases in resource use could result in additional costs or loss of productivity for hospitals. Implementation of long shifts should be questioned.

A mixed methods study of the impact of consultant overnight working in an English Emergency Department.

BACKGROUND: There is a growing expectation that consultant-level doctors should be present within an ED overnight. However, there is a lack of robust evidence substantiating the impact on patient waiting times, safety or the workforce. OBJECTIVES: To evaluate the impact of consultant-level doctors overnight working in ED in a large university hospital. METHODS: We conducted a controlled interrupted time series analysis to study ED waiting times before and after the introduction of consultant night working. Adverse event reports (AER) were used as a surrogate for patient safety. We conducted interviews with medical and nursing staff to explore attitudes to night work. RESULTS: The reduction seen in average time in department relative to the day, following the introduction of consultant was non-significant (-12 min; 95% CI -28 to 4, p=0.148). Analysis of hourly arrivals and departures indicated that overnight work was inherited from the day. There were three (0.9%) moderate and 0 severe AERs in 1 year. The workforce reported that night working had a negative impact on sleep patterns, performance and well-being and there were mixed views about the benefits of consultant night presence. Additional time off during the day acted as compensation for night work but resulted in reduced contact with ED teams. CONCLUSIONS: Our single-site study was unable to demonstrate a clinically important impact of consultant night working on total time patients spend in the department. Our analysis suggests there may be more potential to reduce total time in department during the day, at our study site. Negative impacts on well-being, and likely resistance to consultant night working should not be ignored. Further studies of night working are recommended to substantiate our results.

[Hygiene in Sleep: Problems of Sleeping Habits in Shift Workers].

Since World War II, Japan has achieved remarkable economic development and has become an advanced country. Particularly in the industrial field, a production system has been developed to reduce the loss of machining time by adopting a shiftwork in factories operating 24 hours a day, which contributes to the improvement of productivity. Nowadays, this shiftwork practice has spread from the industrial field to other businesses such as 24-hour entertainment facilities and convenience stores, which lead to sleep deprivation in Japanese society. Even at home, certain conditions adversely affect sleeping habits. We are concerned about the risks of physical and mental health, impairments posed by the use of tablets, PCs, smartphones, and other devices so popular in today's Japan, as they delay sleep. It is urgent to improve poor sleeping habits because their outcomes such as sleep disorders and deprivation may also lead to traffic and industrial accidents.

Does Implementation of Biomathematical Models Mitigate Fatigue and Fatigue-related Risks in Emergency Medical Services Operations? A Systematic Review.

BACKGROUND: Work schedules like those of Emergency Medical Services (EMS) personnel have been associated with increased risk of fatigue-related impairment. Biomathematical modeling is a means of objectively estimating the potential impacts of fatigue on performance, which may be used in the mitigation of fatigue-related safety risks. In the context of EMS operations, our objective was to assess the evidence in the literature regarding the effectiveness of using biomathematical models to help mitigate fatigue and fatigue-related risks. METHODS: A systematic review of the evidence evaluating the use of biomathematical models to manage fatigue in EMS personnel or similar shift workers was performed. Procedures proposed by the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methodology were used to summarize and rate the certainty in the evidence. Potential bias attached to retained studies was documented using the Cochrane Collaboration's Risk of Bias tool for experimental studies. RESULTS: The literature search strategy, which focused on both EMS personnel and non-EMS shift workers, yielded n = 2,777 unique records. One paper, which investigated non-EMS shift workers, met inclusion criteria. As part of a larger effort, managers and dispatchers of a trucking operation were provided with monthly biomathematical model analyses of predicted fatigue in the driver workforce, and educated on how they could reduce predicted fatigue by means of schedule adjustments. The intervention showed a significant reduction in the number and cost of vehicular accidents during the period in which biomathematical modeling was used. The overall GRADE assessment of evidence quality was very low due to risk of bias, indirectness, imprecision, and publication bias. CONCLUSIONS: This systematic review identified no studies that investigated the impact of biomathematical models in EMS operations. Findings from one study of non-EMS shift workers were favorable toward use of biomathematical models as a fatigue mitigation scheduling aid, albeit with very low quality of evidence pertaining to EMS operations. We propose three focus areas of research priorities that, if addressed, could help better elucidate the utility and impact of biomathematical models as a fatigue-mitigation tool in the EMS environment.

Chronotype and work shift in nursing workers of university hospitals.

OBJECTIVE:: To identify the predominant chronotype in nursing workers who work in surgical clinics of university hospitals and to verify the association with work shift. METHOD:: Cross-sectional study, performed in surgical clinics of university hospitals in the Southern region of Brazil. The sample of 270 nursing workers answered questions of socio-occupational characterization, of health and the Morningness-Eveningness Questionnaire of Horne and Östberg. We performed a descriptive and bivariate analysis with the help of the SPSS software and confidence interval of 95%. RESULTS:: The indifferent chronotype predominated (45.2%). There were significant differences between occupational categories and variables "age" (p<0.001), "use of medication" (p=0.035) and "choice of work shift" (p=0.001). There was an association between the chronotype and the variables "work leave due to illness" (p=0.021), "children" (p=0.025), "use of medication" (p=0.018) and "work shift" (p=0.001). CONCLUSION:: The chronotype remained indifferent, and the results confirmed association between chronotype and work shift. OBJETIVO:: Identificar o cronotipo predominante em trabalhadores de enfermagem que atuam em clínicas cirúrgicas de hospitais universitários e verificar associação com o turno de trabalho. MÉTODO:: Estudo transversal, realizado em clínicas cirúrgicas de hospitais universitários da região Sul do Brasil. A amostra de 270 trabalhadores de enfermagem respondeu questões de caracterização sociolaboral, de saúde e o Questionário de Matutinidade-Vespertinidade de Horne e Östberg. Realizou-se análise descritiva e bivariada com auxílio do software SPSS e intervalo de confiança de 95%. RESULTADOS:: Predominou o cronotipo indiferente (45,2%). Houve diferença significativa entre as categorias profissionais e as variáveis "idade" (p<0,001), "uso de medicação" (p=0,035) e "opção pelo turno de trabalho" (p=0,001). Foi identificada associação entre o cronotipo e as variáveis "afastado do trabalho por motivo de doença" (p=0,021), "filho(s)" (p=0,025), "uso de medicação" (p=0,018) e "turno de trabalho" (p=0,001). CONCLUSÃO:: Predominou o cronotipo indiferente, e os resultados confirmaram a associação entre cronotipo e turno de trabalho.

Chronotype and work shift in nursing workers of university hospitals / Cronotipo y turno de trabajo en trabajadores de enfermería de hospitales universitarios / Cronotipo e turno de trabalho em trabalhadores de enfermagem de hospitais universitários

ABSTRACT Objective: To identify the predominant chronotype in nursing workers who work in surgical clinics of university hospitals and to verify the association with work shift. Method: Cross-sectional study, performed in surgical clinics of university hospitals in the Southern region of Brazil. The sample of 270 nursing workers answered questions of socio-occupational characterization, of health and the Morningness-Eveningness Questionnaire of Horne and Östberg. We performed a descriptive and bivariate analysis with the help of the SPSS software and confidence interval of 95%. Results: The indifferent chronotype predominated (45.2%). There were significant differences between occupational categories and variables "age" (p<0.001), "use of medication" (p=0.035) and "choice of work shift" (p=0.001). There was an association between the chronotype and the variables "work leave due to illness" (p=0.021), "children" (p=0.025), "use of medication" (p=0.018) and "work shift" (p=0.001). Conclusion: The chronotype remained indifferent, and the results confirmed association between chronotype and work shift.

RESUMEN Objetivo: Identificar el cronotipo predominante en trabajadores de enfermería que actúan en clínicas quirúrgicas de hospitales universitarios y verificar asociación con el turno de trabajo. Método: Estudio transversal realizado en clínicas quirúrgicas de hospitales universitarios de la región sur de Brasil. La muestra de 270 trabajadores de enfermería respondió cuestiones de caracterización sociolaboral, de salud y el Cuestionario de Matutinidad-Vespertinidad de Horne y Östberg. Se realizó un análisis descriptivo y bivariado con ayuda del software SPSS y un intervalo de confianza del 95%. Resultados: Predominó el cronotipo intermedio (45,2%). Se observó una diferencia significativa entre las categorías profesionales y las variables "edad" (p <0,001), "uso de medicación" (p = 0,035) y "opción por el turno de trabajo" (p = 0,001). Se identificó asociación entre el cronotipo y las variables "alejado del trabajo por motivo de enfermedad" (p = 0,021), "hijo (s)" (p = 0,025), "uso de medicación" (p = 0,018) y "turno de trabajo" (p = 0,001). Conclusión: Predominó el cronotipo intermedio, y los resultados confirmaron la asociación entre cronotipo y turno de trabajo.

RESUMO Objetivo: Identificar o cronotipo predominante em trabalhadores de enfermagem que atuam em clínicas cirúrgicas de hospitais universitários e verificar associação com o turno de trabalho. Método: Estudo transversal, realizado em clínicas cirúrgicas de hospitais universitários da região Sul do Brasil. A amostra de 270 trabalhadores de enfermagem respondeu questões de caracterização sociolaboral, de saúde e o Questionário de Matutinidade-Vespertinidade de Horne e Östberg. Realizou-se análise descritiva e bivariada com auxílio do software SPSS e intervalo de confiança de 95%. Resultados: Predominou o cronotipo indiferente (45,2%). Houve diferença significativa entre as categorias profissionais e as variáveis "idade" (p<0,001), "uso de medicação" (p=0,035) e "opção pelo turno de trabalho" (p=0,001). Foi identificada associação entre o cronotipo e as variáveis "afastado do trabalho por motivo de doença" (p=0,021), "filho(s)" (p=0,025), "uso de medicação" (p=0,018) e "turno de trabalho" (p=0,001). Conclusão: Predominou o cronotipo indiferente, e os resultados confirmaram a associação entre cronotipo e turno de trabalho.