Shift work and long work hours and their association with chronic health conditions: A systematic review of systematic reviews with meta-analyses

Sleep quality and the need for recovery among nurses working irregular shifts: A cross-sectional study

BACKGROUND

Shift work affects the mental and physical health of nurses, yet the effect of working irregular shifts on sleep and its association with the need for recovery is under-explored.

OBJECTIVE

The purpose of this study was to investigate the sleep quality of nurses working irregular shifts, including night shifts, and to determine whether sleep quality is associated with the need for recovery.

METHODS

This cross-sectional study included 405 nurses working irregular shifts. Data were collected using an online questionnaire that included sociodemographic characteristics, the Sleep-Wake Experience List, sleep problems, sleep duration, and the Need for Recovery scale. Data analyses included descriptive statistics, chi-square tests, t-tests, logistic and multiple linear regressions.

RESULTS

Nurses who worked irregular shifts had poor sleep quality. Those who also worked night shifts, had significantly poorer sleep quality and experienced more difficulties in daily functioning than those who did not work night shifts. Sleep quality was significantly associated with the need for recovery and this remained so after controlling for confounding variables (β= .554, p = .001).

CONCLUSION

The findings indicate that in nurses who work irregular shifts, the sleep quality is low. In this group, the sleep quality in nurses who work night shifts is lower than in nurses who do not work night shifts. Furthermore, better sleep quality was associated with lower need for recovery. These findings suggest that improving sleep quality in nurses working irregular shifts may lower their need for recovery, which may improve health, and reduce burnout and sickness absence.

Prospective associations of occupational and leisure-time physical activity with risk of diabetes: a cohort study from the United States

OBJECTIVES

Leisure-time physical activity (LTPA) can reduce the risk of incident diabetes, whereas the role of occupational physical activity (OPA) in developing diabetes is still unclear due to conflicting evidence. Moreover, the joint associations of OPA and LTPA with incident diabetes among US workers have not yet been systematically examined. The objective of this study was to assess the independent and joint associations of OPA and LTPA with incident diabetes.

METHODS

This prospective cohort study included 1406 workers free from diabetes at baseline (2004-2006) from the national, population-based Mid-life in the United States (MIDUS) study. Associations of OPA and LTPA at baseline with incident diabetes during 9 years of follow-up were examined using Poisson regression models. High OPA was defined based on engagement in physical demands at work, and high LTPA was defined as participation in moderate or vigorous LTPA at least once per week.

RESULTS

High OPA was associated with an increased risk of diabetes compared to low OPA (adjusted risk ratios and 95% confidence interval = 1.52 [1.04, 2.22]), while high LTPA was associated with a decreased risk of diabetes compared to low LTPA (0.66 [0.44, 0.97]). Diabetes risk was the highest among workers with high OPA and low LTPA (2.30 [1.30, 4.07]).

CONCLUSIONS

In a national, population-based prospective cohort study of US workers, high OPA was associated with an elevated risk of diabetes, while high LTPA was associated with a decreased diabetes risk. The combination of high OPA and low LTPA exhibited the greatest risk of diabetes.

Silver Lining Study: Missileer Fatigue Mitigation During 2020 Coronavirus Pandemic

INTRODUCTION

The U.S. Air Force's Intercontinental Ballistic Missile (ICBM) force stands ready to launch weapons 365 days per year. Since its inception, missileers vigilantly operate launch consoles on a 3-day cycle: minimum 24-hour alert-shift/24-hour travel-admin/24-hour off, leading to concerns that health, morale, and alertness are chronically impacted. In 2020, a Missileer Occupational Health Assessment (OHA) revealed 76% of respondents struggle with being rested for duty and 29% of respondents never feel adequately rested for duty. Later that year, 20th Air Force initiated long-duration operations to safeguard from the SARS CoV-2 (COVID-19) Pandemic, resulting in increased operations tempo, and exacerbating crew fatigue.341st Operations Group and 341st Medical Group at Malmstrom Air Force Base enacted interventions to mitigate crew fatigue and support continued readiness during pandemic operations. They recorded, analyzed, and compiled findings in this report, including recommendations for long-term ICBM operations at Missile Wings.

MATERIALS AND METHODS

All participants were Nuclear and Missile Operations Officers, or missileers, were continuously evaluated with qualitative and quantitative measures to ensure safety of the force during a period of unprecedented change. Interventions implemented and evaluated during the 9-month period included: environmental modifications, scheduling changes, and crew education on fatigue management, nutrition, anticipatory sleep preparation, and fitness. Most notably, the 341st Operations Group examined various 3-person and 4-person shift-length and alert duration schedules. Psychomotor vigilance testing results validated safety of operators and delta between pre- and post-shift measurements. Crew force readiness trends were analyzed for force-health awareness. Pre- and post-OHA results were compared for subjective changes. Fatigue and health-related outcomes were collected from a safety monitoring effort during standard and COVID-19 operations at 341st Missile Wing.

RESULTS

Findings from qualitative and quantitative data indicate the optimal schedule is a 3-week cycle:7-day alert/7-day recovery/7-day training-administrative utilizing 4-member or 3-member crews for low tempo operations. Crews experimented with shift-lengths of 24hrs-on/24hrs-off, 16hrs-on/8hrs-off, and 12hrs-on/12hrs-off. Maximum safe alert duration is 7 days due to task fatigue onset between 8 and 10 days. Short and long duration Duties Not to Include Flight (DNIF) (also known as Duties Not to Include Alert (DNIA) among missileers) rates decreased from the first to last month of the period by 74.6% and 79.2%, respectively. The number of alerts missed per month decreased 86% from baseline. The 2021 OHA found a 7% decline in members seeking separation, and absence of sleep, fatigue, and physical or mental health as missileer concerns.

CONCLUSIONS

This analysis has identified a sustainable alert rotation of 7/7/7 with emphasis on protected recovery and training time and has been continued after concluding pandemic operations, creating consistent schedule stability where there once was none. If executed properly, this alert rotation, regardless of shift-length selected, has potential to improve trust between crews and leadership, provides adequate recovery time between alerts to maintain health, and improves wellness, family stability, morale, unit cohesion, and crew force retention. Notably, all Air Force Global Strike Missile Operations Groups adjusted scheduling practices to align with these findings.

Exploring workability in an older working population: associations with cognitive functioning, sleep quality, and technostress

Objective

This observational study investigates workability and its associations with cognitive functioning, sleep quality and technostress among an older working population, also shedding light on potential differences between two occupational categories with different work schedules.

Methods

Workers aged over 50, employed in different working sectors (banking/finance, chemical and metal-mechanic industry) were administered a self- report questionnaire including Work Ability Index (WAI), cognitive tests (Stroop Color Task, Corsi Blocks, Digit Span), sleep quality questionnaires (Pittsburgh Sleep Quality Index-PSQI; Insomnia Severity Index-ISI; Ford Insomnia Response to Stress Test-FIRST) and technostress scale. Linear regression models evaluated associations among variables, interaction effects investigated potential moderators.

Results

A total of 468 aged workers categorized as white (WCWs; N = 289, 62%) or blue collars (BCWs; N = 179, 38%) were enrolled; most BCWs (N = 104; 58%) were night shift workers. WCWs reported higher workability, cognitive functioning, sleep quality and lower technostress (except for invasion and privacy subscales) than BCWs. Associations between cognitive functioning and workability were statistically significant only for BCWs [slopes equal to 0.2 (0.33), 0.8 (0.34), -0.02 (0.001) for Memory Span Corsi, Block Span Digit and Interference Speed respectively]; additionally, sleep quality significantly moderated this association (p = 0.007). Higher levels of technostress were associated with lower workability, and this relationship was stronger for BCWs.

Conclusion

The aging of the workforce has important implications for occupational health and safety. Our findings suggest potential interventions and protective measures to promote older workers' wellbeing; blue-collar workers particularly should benefit from tailored intervention to sustain workability and prevent technostress, considering the role of healthy sleep habits promotion.

Effects of fatigue on anaesthetist well-being and patient safety: a narrative review

The elements that render anaesthesia a captivating profession can also foster stress and fatigue. Professionals considering anaesthesia as a career choice should have a comprehensive understanding of the negative consequences of fatigue and its implications for clinical performance and of the available preventive measures. Available evidence suggests that factors unrelated to patient characteristics or condition can affect clinical outcomes where anaesthetists are involved. Workload, nighttime work, and fatigue are persistent issues in anaesthesia and are perceived as presenting greater perioperative risks to patients. Fatigue seems to negatively affect both physical and mental health of anaesthetists. Existing evidence justifies specific interventions by institutions, stakeholders, and scientific societies to address the effects of anaesthetist fatigue. This narrative review summarises current knowledge regarding the effects of fatigue on anaesthetist well-being and patient safety, and discusses potential preventive solutions.

The influence of shift work: A bibliometric analysis of research progress and frontiers on health effects

Shift work has been found to disrupt the circadian system, leading to negative health effects. The objective of this study was to assess the progress and frontiers in research on the health-related influence of shift work. The study analyzed 3,696 data points from Web of Science, using the bibliometric software CiteSpace to visualize and analyze the field. The results showed a steady increase in annual publications, particularly in the last 5 years, with a rapid increase in publications from China. The United States contributed the most to the number of publications and worldwide collaborations. The most prolific institution and author were the Brigham and Women's Hospital and Professor Bjorn Bjorvatn, respectively. The Journal of Chronobiology International ranked at the top and focused primarily on shift worker research. In the first decade of study, the primary focus was on the associations between shift work and cardiovascular disease and metabolic disorders. Over time, research on the health effects of shift work has expanded to include cancer and mental health, with subsequent studies investigating molecular mechanisms. This study provides a comprehensive and intuitive analysis of the negative health impacts of shift work. It highlights existing research hotspots and provides a roadmap for future studies. Further research is needed to explore the adverse health consequences and related mechanisms of shift work exposure, as well as interventions to mitigate its health effects.

Night shift work and cardiovascular diseases among employees in Germany: five-year follow-up of the Gutenberg Health Study

OBJECTIVE

This study aimed to determine if there is an increased risk of incident cardiovascular diseases (CVD) resulting from cumulative night shift work in the German population-based Gutenberg Health Study (GHS).

METHODS

We examined working participants of the GHS at baseline and after five years. Cumulative night shift work in the 10 years before baseline was assessed and categorized as low (1-220 nights ≙ up to 1 year), middle (221-660 nights ≙ 1-3 years), and high (>660 nights ≙ more than 3 years) night shift exposure. Hazard ratios (HR) were estimated for incident "quality-assured CVD events" using Cox proportional hazard models.

RESULTS

At baseline, 1092 of 8167 working participants performed night shift work. During the follow-up, 202 incident cardiovascular events occurred. The crude incidence rates for CVD per 1000 person-years were 6.88 [95% confidence interval (CI) 4.80-9.55] for night shift workers and 5.19 (95% CI 4.44-6.04) for day workers. Cumulative incidence curves showed a higher cumulative incidence in workers exposed to night shift work compared to day workers after five years. The adjusted HR for incident CVD events were 1.26 (95% CI 0.68-2.33), 1.37 (95% CI 0.74-2.53) and 1.19 (95% CI 0.67-2.12) for employees in the low, middle and high night shift categories compared to employees without night shift work, respectively.

CONCLUSIONS

The observed tendencies indicate that night shift work might be negatively associated with cardiovascular health. We expect the continued follow-up will clarify the long-term impact of night shift work.

Association of diet, lifestyle, and chronotype with metabolic health in Ukrainian adults: a cross-sectional study

Morning chronotypes are associated with healthier metabolic profiles and lifestyles compared to evening chronotypes. However, limited research examined the relationship between chronotype, dietary intake, and metabolic health using accurate measures such as food records. This cross-sectional study aimed to investigate the association between chronotype, dietary intake, and metabolic health markers in a cohort of Ukrainian individuals. Chronotypes were determined using the Morningness-Eveningness Questionnaire (MEQ) in 110 healthy to obese individuals (30-75 years) without type 2 diabetes. Dietary intake was derived from weighed seven days food diaries, anthropometrics and blood markers of glucose and lipid metabolism were measured. Morning chronotypes were significantly older and exhibited distinct dietary patterns, including lower intake of fat and animal protein and higher intake of carbohydrates when compared to evening chronotypes (p < 0.01). Higher MEQ scores, reflecting a tendency toward a morning chronotype, were associated with lower BMI, waist circumference, fasting triglycerides, and glucose (p < 0.05). Further, being of morning chronotype predicted better overall metabolic health. These associations remained significant after adjusting for confounders. The findings suggest that morning chronotypes have a different dietary pattern characterized by a more balanced diet and favorable metabolic profile. Synchronizing daily routines with morning preferences could positively influence metabolic health.

Alterations of functional brain activity and connectivity in female nurses working on long-term shift

AIM

To investigate the alterations of functional brain activity and connectivity in female nurses working on long-term shifts and explore their correlations with work-related psychological traits.

DESIGN

An exploratory cross-sectional study.

METHODS

Thirty-five female nurses working on long-term shifts (shift nurses) and 35 female nurses working on fixed days (fixed nurses) were enrolled. After assessing the work-related psychological traits, including burnout, perceived stress, anxiety, and depression of nurses, the fractional amplitude of low-frequency fluctuations (fALFF) and region of interest (ROI)-based functional connectivity (FC) analyses were performed to investigate the differences of brain spontaneous activity and functional connectivity between these two groups of nurses. Thereafter, correlations between the functional brain parameters (fALFF and FC) and clinical metrics were investigated among the shift nurses.

RESULTS

Compared to fixed nurses, shift nurses had higher burnout, perceived stress and depression scores, lower fALFF in the right dorsolateral prefrontal cortex (dlPFC), left and right superior parietal lobule (SPL), bilateral anterior cingulate cortex (ACC), and higher fALFF in the right superior/middle temporal gyrus, as well as decreased FC between the right dlPFC (the selected ROI) and bilateral ACC, left and right inferior frontal/orbitofrontal gyrus (IFG/IOFG), right SPL, and left middle occipital gyrus (voxel-level p < 0.001, cluster level p < 0.05, GRF correction). Correlation analyses demonstrated that the fALFF value of the right dlPFC was significantly correlated with the burnout and anxiety scores, the FC value of the right dlPFC-right SPL was correlated with the perceived stress and burnout scores, the FC value of the right dlPFC-right IFG/IOFG was correlated with the burnout score in shift nurses (p < 0.05).

CONCLUSION

Shift nurses had work-related altered functional activity and connectivity in the right frontoparietal network, which provided objective and visualised evidence to clarify the hazards of long-term shift work on female nurses.

PATIENT OR PUBLIC CONTRIBUTION

Seventy nurses participated deeply as subjects in this study. These findings are expected to draw managers' attention to the harmful influences of shift work on nurses.

Circadian immunity from bench to bedside: a practical guide

The immune system is built to counteract unpredictable threats, yet it relies on predictable cycles of activity to function properly. Daily rhythms in immune function are an expanding area of study, and many originate from a genetically based timekeeping mechanism known as the circadian clock. The challenge is how to harness these biological rhythms to improve medical interventions. Here, we review recent literature documenting how circadian clocks organize fundamental innate and adaptive immune activities, the immunologic consequences of circadian rhythm and sleep disruption, and persisting knowledge gaps in the field. We then consider the evidence linking circadian rhythms to vaccination, an important clinical realization of immune function. Finally, we discuss practical steps to translate circadian immunity to the patient's bedside.

The importance of sleep regularity: a consensus statement of the National Sleep Foundation sleep timing and variability panel

OBJECTIVE

To develop and present consensus findings of the National Sleep Foundation sleep timing and variability panel regarding the impact of sleep timing variability on health and performance.

METHODS

The National Sleep Foundation assembled a panel of sleep and circadian experts to evaluate the scientific evidence and conduct a formal consensus and voting procedure. A systematic literature review was conducted using the NIH National Library of Medicine PubMed database, and panelists voted on the appropriateness of 3 questions using a modified Delphi RAND/UCLA Appropriateness Method with 2 rounds of voting.

RESULTS

The literature search and panel review identified 63 full text publications to inform consensus voting. Panelists achieved consensus on each question: (1) is daily regularity in sleep timing important for (a) health or (b) performance? and (2) when sleep is of insufficient duration during the week (or work days), is catch-up sleep on weekends (or non-work days) important for health? Based on the evidence currently available, panelists agreed to an affirmative response to all 3 questions.

CONCLUSIONS

Consistency of sleep onset and offset timing is important for health, safety, and performance. Nonetheless, when insufficient sleep is obtained during the week/work days, weekend/non-work day catch-up sleep may be beneficial.

Long working hours and self-rated health in the national Brazilian working population: gender and employment status differences, 2019

BACKGROUND

The regulation of working hours is governed by legal standards in formal employment. While the association between long working hours and various health outcomes has been extensively studied, there is limited evidence regarding Brazil. The objective of this study was to investigate the association among working hours, employment status, and self-rated health (SRH), taking into account differences between men and women in a national representative sample of the working population in Brazil.

METHODS

A cross-sectional study was conducted among a representative sample of 33,713 workers in Brazil to assess self-rated health (SRH). We examined the associations between working hours and employment status, categorizing working hours as standard (40-44 h per week) or long (> 44 h per week), and employment status as formal or informal. Logistic regression models were employed, adjusting for sociodemographic, occupational characteristics, and health behaviors. Probabilities of negative SRH were calculated for men and women in different exposure profiles. Results were stratified by gender, and 95% confidence intervals (CIs) were applied to the findings.

RESULTS

The prevalence of long working hours was higher among informal workers for both men and women. Adjusted odds ratio (AOR) results revealed that informal employment (AORwomen = 1.53; 95% CI: 1.13-2.07 and AORmen = 1.55; 95% CI: 1.22-1.96) and long working hours (AORwomen = 1.23; 95% CI: 1.06-1.43 and AORmen = 1.14; 95% CI: 1.00-1.30) were independently associated with negative SRH. Significant interactions between long working hours and informal employment were observed. Among individuals with the same exposure profile, women who engaged in long working hours had a higher probability of reporting negative SRH compared to men.

CONCLUSIONS

The results of this study are in line with the literature, as differences between men and women in the likelihood of negative self-rated health were observed. The adverse health effects underscore the importance of implementing intersectoral actions to inform the revision of regulations concerning weekly working hours and the expansion of informal employment in low- and middle-income countries.

Fatigue and somatization in shift-workers: Effects of depression and sleep

OBJECTIVE

We investigated the differences in fatigue and somatization between shift and non-shift workers and explored the effects of sleep and depression on fatigue and somatization in shift workers.

METHODS

In total, 4543 shift workers and 2089 non-shift workers completed self-reported questionnaires. The Center for Epidemiologic Studies Depression Scale (CESD), Pittsburgh Sleep Quality Index (PSQI), Fatigue Severity Scale (FSS), and Somatization subscale of the Symptom Checklist 90-item version (SCL-SOM) were used to measure depression, sleep quality, fatigue, and somatization, respectively. Fatigue and somatization were compared between shift and non-shift workers after controlling for different sets of covariates.

RESULTS

Compared to non-shift workers, shift workers reported higher FSS (mean difference: 2.19 ± 0.30, p < 0.01) and SCL-SOM (mean difference: 1.77 ± 0.21, p < 0.01) scores after controlling for age, gender, presence of medical illness, occupational category, monthly income, length of service, and weekly working hours. The between-group difference in FSS score was no longer significant after additionally controlling for CES-D (p = 0.15) or PSQI (p = 0.18). The between-group difference in SCL-SOM score showed only non-significant trends after additionally controlling for CES-D (p = 0.09) or PSQI (p = 0.07). The group difference in SCL-SOM scores disappeared after controlling for both CES-D and PSQI scores (p = 0.99).

CONCLUSIONS

Shift workers had higher fatigue and somatization levels than non-shift workers and the group difference was associated with disturbed sleep and depressed mood in shift workers.

Self-Employment, Working Hours, and Hypertension by Race/Ethnicity in the USA

There is a large literature on work-related characteristics and hypertension, but studies on self-employment, longer working hours, and hypertension are mixed. Assessments of self-employment should be extended to account for people with part-time self-employment (i.e., employees also earning income from self-employment). The aim of this study was to determine the association of different types of self-employment with hypertension among adults by race/ethnicity and to assess whether longer working hours moderated these associations. Using data from the 2007-2018 National Health and Nutrition Examination Survey, measured hypertension (blood pressure ≥ 140/90 mm Hg) was assessed and employment categories included employees, part-time self-employment (i.e., employee with self-employment income), or full-time self-employment. Modified Poisson regressions and multiplicative interaction terms were used. Having full-time self-employment was associated with lower relative risk (RR) of hypertension compared to employees among Black (RR = 0.77, 95% confidence interval (CI) = 0.61-0.96) and White men (RR = 0.77, 0.65-0.93) compared to employees. Full-time self-employment was associated with higher risk of hypertension (RR = 1.36, 95% CI = 1.01-1.82) compared to employees among Hispanic women, while part-time self-employment was associated with lower risk (RR = 0.69, 95% CI = 0.48-0.98). Among White women, part-time self-employment was associated with higher relative risk of hypertension (RR = 1.27, 95% CI = 1.05-1.53) compared to employees. There were significant interactions between employment categories and longer working hours among Hispanic women as well as Black women and men. The results suggest that self-employment categories and longer working hours impact hypertension by race/ethnicity and sex. Because the number of full-time and part-time self-employed adults has increased, the health of this particular subgroup of workers should be further addressed.

Non-dipping blood pressure pattern in pediatricians during on-duty

INTRODUCTION

People with a reduced nighttime dip in blood pressure have an increased cardiovascular risk. Our objective was to describe the different patterns in blood pressure (BP) among pediatricians who work in long on-duty shifts in relation with sex, medical rank and sleeping time.

METHODS

Descriptive, cross-sectional, two-center study. On duty pediatric Resident physicians and pediatric Consultants were recruited between January 2018 and December 2021.

RESULTS

Fifty-one physicians were included in the study (78.4% female, 66.7% Resident physicians). Resident physicians had a higher night/day ratio (0.91 vs 0.85; p<0.001) and a shorter nighttime period (3.87 vs 5.41, p<0.001) than Consultants. Physicians sleeping less than 5h had a higher night/day ratio (0.91 vs 0.87, p=0.014). Being a Resident showed a ∼4.5-fold increased risk of having a non-dipping BP pattern compared to Consultants.

CONCLUSION

We found a potential link between both being a Resident and, probably, having shorter sleeping time, and the non-dipping BP pattern in physicians during prolonged shifts.

Home-Based Dynamics of Sleepiness-Related Conditions Starting at Biological Evening and Later (Beyond Working)

Shift work requires round-the-clock readiness to perform professional duties, and the workers' performance highly depends on their sleepiness level, which can be underestimated during a shift. Various factors, including the time of day, can influence sleepiness in shift workers. The objective of this study was to explore the dynamics of sleepiness-related conditions assessed through heart rate variability analysis, starting from the biological evening and continuing in vivo (at home), without the need for artificial alertness support. The participants solely performed regular evening household duties. A total of 32 recordings were collected from the Subjective Sleepiness Dynamics Dataset for analysis. At 8:00 p.m. and every 30 min thereafter, the participants completed cyclic sleepiness scales (the KSS and the SSS) until the time they went to bed, while their heart rate was recorded. The results of the study indicated that during the biological evening, high sleepiness is associated with a 'stressed' condition characterized by higher sympathetic activation. Later on, it is associated with a 'drowsy' condition characterized by higher parasympathetic activation and a decline in heart rate variability. Our findings provide evidence that the type of condition experienced during high sleepiness depends on the biological time. This should be taken into account when managing work regimes in shift work and developing alertness detectors.

Doctors' alertness, contentedness and calmness before and after night shifts: a latent profile analysis

BACKGROUND

While night shifts are crucial for patient care, they threaten doctors' well-being and performance. Knowledge of how the impact of night shifts differs for doctors is needed to attenuate the adverse effects of night shifts. This study aimed to obtain more precise insight into doctors' feelings surrounding night shift by: identifying profiles based on doctors' alertness, contentedness and calmness scores before and after night shifts (research question (RQ) 1); assessing how doctors' pre- and post-shift profiles change (RQ2); and determining associations of doctors' demographics and shift circumstances with alertness, contentedness and calmness change (RQ3).

METHODS

Latent Profile Analysis using doctors' pre- and post-shift self-rated alertness, contentedness and calmness scores was employed to identify pre- and post-shift profiles (RQ1). A cross-tabulation revealed pre- and post-shift profile changes (RQ2). Multiple regressions determined associations of demographics (i.e. age, sex, specialty) and night shift circumstances (i.e. hours worked pre-call, hours awake pre-call, shift duration, number of consecutive shifts, total hours of sleep) with alertness, contentedness and calmness change (RQ3).

RESULTS

In total, 211 doctors participated with a mean age of 39.8 ± 10 years; 47.4% was male. The participants included consultants (46.4%) and trainees (53.6%) of the specialties surgery (64.5%) and obstetrics/gynaecology (35.5%). Three pre-shift (Indifferent, Ready, Engaged) and four post-shift profiles (Lethargic, Tired but satisfied, Excited, Mindful) were found. Most doctors changed from Ready to Tired but satisfied, with alertness reducing most. Age, specialty, sleep, shift duration and the number of consecutive shifts associated with alertness, contentedness and calmness changes.

CONCLUSIONS

The results provided nuanced insight into doctors' feelings before and after night shifts. Future research may assess whether specific subgroups benefit from tailored interventions.

Development of a Multilevel Model to Identify Patients at Risk for Delay in Starting Cancer Treatment

Importance

Delays in starting cancer treatment disproportionately affect vulnerable populations and can influence patients' experience and outcomes. Machine learning algorithms incorporating electronic health record (EHR) data and neighborhood-level social determinants of health (SDOH) measures may identify at-risk patients.

Objective

To develop and validate a machine learning model for estimating the probability of a treatment delay using multilevel data sources.

Design, Setting, and Participants

This cohort study evaluated 4 different machine learning approaches for estimating the likelihood of a treatment delay greater than 60 days (group least absolute shrinkage and selection operator [LASSO], bayesian additive regression tree, gradient boosting, and random forest). Criteria for selecting between approaches were discrimination, calibration, and interpretability/simplicity. The multilevel data set included clinical, demographic, and neighborhood-level census data derived from the EHR, cancer registry, and American Community Survey. Patients with invasive breast, lung, colorectal, bladder, or kidney cancer diagnosed from 2013 to 2019 and treated at a comprehensive cancer center were included. Data analysis was performed from January 2022 to June 2023.

Exposures

Variables included demographics, cancer characteristics, comorbidities, laboratory values, imaging orders, and neighborhood variables.

Main Outcomes and Measures

The outcome estimated by machine learning models was likelihood of a delay greater than 60 days between cancer diagnosis and treatment initiation. The primary metric used to evaluate model performance was area under the receiver operating characteristic curve (AUC-ROC).

Results

A total of 6409 patients were included (mean [SD] age, 62.8 [12.5] years; 4321 [67.4%] female; 2576 [40.2%] with breast cancer, 1738 [27.1%] with lung cancer, and 1059 [16.5%] with kidney cancer). A total of 1621 (25.3%) experienced a delay greater than 60 days. The selected group LASSO model had an AUC-ROC of 0.713 (95% CI, 0.679-0.745). Lower likelihood of delay was seen with diagnosis at the treating institution; first malignant neoplasm; Asian or Pacific Islander or White race; private insurance; and lacking comorbidities. Greater likelihood of delay was seen at the extremes of neighborhood deprivation. Model performance (AUC-ROC) was lower in Black patients, patients with race and ethnicity other than non-Hispanic White, and those living in the most disadvantaged neighborhoods. Though the model selected neighborhood SDOH variables as contributing variables, performance was similar when fit with and without these variables.

Conclusions and Relevance

In this cohort study, a machine learning model incorporating EHR and SDOH data was able to estimate the likelihood of delays in starting cancer therapy. Future work should focus on additional ways to incorporate SDOH data to improve model performance, particularly in vulnerable populations.

The impacts of working time flexibilization on occupational safety and health: an expert survey

The policy proposal by the current Korean government that proposes flexible overtime rules is causing social controversy. This study has explored the 612 experts' opinions on the occupational safety and health impacts of the policy using an online self-report survey. They expected short-term overwork (87.25%), overwork inequality (86.44%), irregular working hours (84.31%), chronic overwork (84.15%), long working hours (83.66%), and unpredictability of working hours (81.86%) as a result of the policy change. They also responded that the policy change would increase industrial accident deaths (87.25%), mental illnesses (87.09%), deaths due to overwork or cardiovascular diseases (83.84%), and accidents (83.33%). They disagreed that the government's flexibilization policy, while agreeing that the necessity of policies on regulating night work (94.77%), guaranteeing wages to eliminate overtime (90.36%), establishing working time regulations for the bogus self-employed (82.84%), and applying the 52-hour workweek system to all workplaces (76.47%). These expert opinions are consistent with previous research on the health effects of working hours.

Engaging Leadership and Psychological Safety as Moderators of the Relationship between Strain and Work Recovery: A Cross-Sectional Study of HSS Employees

Work in the health and social sector (HSS) is highly straining and therefore recovery from work needs to be promoted. Less is known on how job resources can be used to alleviate job strain and increase recovery from work. Thus, we analyzed the following: the association between job demands and work recovery; the connections of engaging leadership and psychological safety to recovery from work; and the moderating effects of engaging leadership and psychological safety on the relationship between strain and recovery from work. This cross-sectional study of 18,155 HSS and 4347 eldercare employees in 2020 using linear regression analysis showed that job strain (p < 0.001) and moral distress (p < 0.001) were associated with decreased recovery from work. Engaging leadership (p < 0.001) and psychologically safe work community (p < 0.001) enhanced recovery from work independently. Engaging leadership mitigated the harmful effect of job strain (p < 0.01) and moral distress (p < 0.05), and psychological safety mitigated the effect of job strain (p < 0.001), but not moral distress (p > 0.05). Thus, it is important to reduce job strain so that employees recover from work. Further job resources such as engaging leadership and psychological safety are important in themselves as they support recovery from work and employees' well-being, but also as they alleviate job demands.

Psychosocial Work Stress and Occupational Stressors in Emergency Medical Services

Emergency medical service (EMS) professionals often experience work stress, which escalated during COVID-19. High job demand in the EMS profession may lead to progressive decline in physical and mental health. We investigated the prevalence of psychosocial job stress in the three levels of EMS: basic, advanced, and paramedic, before and during the COVID-19 pandemic. EMS professionals (n = 36) were recruited from EMS agencies following the Institutional Review Board approval. Participants took surveys on demographics, personal characteristics, chronic diseases, and work schedules. Job stress indicators, namely the effort–reward ratio (ERR) and overcommitment (OC), were evaluated from survey questionnaires using the effort–reward imbalance model. Associations of job stress indicators with age, sex, body mass index, and working conditions were measured by logistic regression. Psychosocial work stress was prevalent with effort reward ratio > 1 in 83% of participants and overcommitment scores > 13 in 89% of participants. Age, body mass index, and work hours showed strong associations with ERR and OC scores. The investigation findings suggested that a psychosocial work environment is prevalent among EMS, as revealed by high ERR, OC, and their correlation with sleep apnea in rotating shift employees. Appropriate interventions may be helpful in reducing psychosocial work stress in EMS professionals.

Longer working hours and musculoskeletal pain: a meta-analysis

Objectives. Musculoskeletal pain is the most common health problem in the workplace, and one of the most important risk factors for this pain is longer working hours. This study aimed to investigate the association between long working hours and musculoskeletal pain. Methods. Based on the keywords, two scientific sources - PubMed and Embase - were reviewed. The time limit search included articles that were published until May 2020 and only studies published in English were eligible. The results of the studies were combined based on random effects and pooled odds ratio (OR) reported. The degree of heterogeneity in all analyses was investigated and reported based on χ² and I² tests. Publishing bias was also measured using statistical tests. Results. Longer working hours are associated with increased musculoskeletal pain with OR = 1.11 and 95% confidence interval (CI) [1.08, 1.14]. The result was OR = 1.52 and 95% CI [1.14, 2.03] in men and OR = 1.11 and 95% CI [1.00, 1.24] in women. Conclusion. Long working hours are an important and threatening factor for musculoskeletal health. Therefore, this issue should be considered in health policy as well as treatment and prevention.

Krüppel-like factor 9 (KLF9) links hormone dysregulation and circadian disruption to breast cancer pathogenesis

BACKGROUND

Circadian disruption is an emerging driver of breast cancer (BCa), with epidemiological studies linking shift work and chronic jet lag to increased BCa risk. Indeed, several clock genes participate in the gating of mitotic entry, regulation of DNA damage response, and epithelial-to-mesenchymal transition, thus impacting BCa etiology. Dysregulated estrogen (17β-estradiol, E2) and glucocorticoid (GC) signaling prevalent in BCa may further contribute to clock desynchrony by directly regulating the expression and cycling dynamics of genes comprising the local breast oscillator. In this study, we investigated the tumor suppressor gene, Krüppel-like factor 9 (KLF9), as an important point of crosstalk between hormone signaling and the circadian molecular network, and further examine its functional role in BCa.

METHODS

Through meta-analysis of publicly available RNA- and ChIP-sequencing datasets from BCa tumor samples and cell lines, and gene expression analysis by RT-qPCR and enhancer- reporter assays, we elucidated the molecular mechanism behind the clock and hormone regulation of KLF9. Lentiviral knockdown and overexpression of KLF9 in three distinct breast epithelial cell lines (MCF10A, MCF7 and MDA-MB-231) was generated to demonstrate the role of KLF9 in orthogonal assays on breast epithelial survival, proliferation, apoptosis, and migration.

RESULTS

We determined that KLF9 is a direct GC receptor target in mammary epithelial cells, and that induction is likely mediated through coordinate transcriptional activation from multiple GC-responsive enhancers in the KLF9 locus. More interestingly, rhythmic expression of KLF9 in MCF10A cells was abolished in the highly aggressive MDA-MB-231 line. In turn, forced expression of KLF9 altered the baseline and GC/E2-responsive expression of several clock genes, indicating that KLF9 may function as a regulator of the core clock machinery. Characterization of the role of KLF9 using complementary cancer hallmark assays in the context of the hormone-circadian axis revealed that KLF9 plays a tumor-suppressive role in BCa regardless of molecular subtype. KLF9 potentiated the anti-tumorigenic effects of GC in E2 receptor + luminal MCF7 cells, while it restrained GC-enhanced oncogenicity in triple-negative MCF10A and MDA-MB-231 cells.

CONCLUSIONS

Taken together, our findings support that dysregulation of KLF9 expression and oscillation in BCa impinges on circadian network dynamics, thus ultimately affecting the BCa oncogenic landscape.

Pregnancy, obstetrical and neonatal outcomes in women exposed to physician-related occupational hazards: a scoping review

OBJECTIVE

Evidence is needed to guide organisational decision making about workplace accommodations for pregnant physicians. Our objective was to characterise the strengths and limitations of current research examining the association between physician-related occupational hazards with pregnancy, obstetrical and neonatal outcomes.

DESIGN

Scoping review.

DATA SOURCES

MEDLINE/PubMed, EMBASE, CINAHL/ EBSCO, SciVerse Scopus and Web of Science/Knowledge were searched from inception to 2 April 2020. A grey literature search was performed on 5 April 2020. The references of all included articles were hand searched for additional citations.

ELIGIBILITY CRITERIA

English language citations that studied employed pregnant people and any 'physician-related occupational hazards', meaning any relevant physical, infectious, chemical or psychological hazard, were included. Outcomes included any pregnancy, obstetrical or neonatal complication.

DATA EXTRACTION AND SYNTHESIS

Physician-related occupational hazards included physician work, healthcare work, long work hours, 'demanding' work, disordered sleep, night shifts and exposure to radiation, chemotherapy, anaesthetic gases or infectious disease. Data were extracted independently in duplicate and reconciled through discussion.

RESULTS

Of the 316 included citations, 189 were original research studies. Most were retrospective, observational and included women in any occupation rather than healthcare workers. Methods for exposure and outcome ascertainment varied across studies and most studies had a high risk of bias in data ascertainment. Most exposures and outcomes were defined categorically and results from different studies could not be combined in a meta-analysis due to heterogeneity in how these categories were defined. Overall, some data suggested that healthcare workers may have an increased risk of miscarriage compared with other employed women. Long work hours may be associated with miscarriage and preterm birth.

CONCLUSIONS

There are important limitations in the current evidence examining physician-related occupational hazards and adverse pregnancy, obstetrical and neonatal outcomes. It is not clear how the medical workplace should be accommodated to improve outcomes for pregnant physicians. High-quality studies are needed and likely feasible.

The Prolonged Effect of Shift Work and the Impact of Reducing the Number of Nightshifts on Arterial Stiffness-A 4-Year Follow-Up Study

AIM

To assess changes in blood pressure (BP) and arterial stiffness among 84 rotating shift and 25 dayworkers (control subjects) at two industrial plants during a 4-year follow-up, and to assess changes in outcome variables among shift workers at the two plants after a reduction in the number of night shifts during the last year of follow-up in one of the plants.

METHODS

We collected demographic data using a questionnaire, examined systolic and diastolic blood pressure (sBP, dBP), central systolic and diastolic aorta pressure (cSP, cDP), augmentation pressure (AP), central pulse pressure (cPP), and pulse wave velocity (PWV). We registered sleep quality. The last 4-14 months of follow-up one plant implemented a 12-week shift plan reducing the total number of night shifts and consecutive night shifts from 16.8 to 14 and from 7.2 to 4. To assess differences in change of outcomes between study groups we applied linear mixed models.

RESULTS

The dayworkers were older, more hypertensive, reported less sleep disturbance, and smoked/snuffed less than the shift workers did. The adjusted annual increase in PWV was 0.34 m/s (95%CI, 0.22, 0.46) among shift workers and 0.09 m/s (95%CI, -0.05, 0.23) in dayworkers, yielding a significant difference of change of 0.25 m/s (95%CI, 0.06, 0.43). No significant differences were found between the two groups of shift workers in any cardiovascular disease (CVD) outcome during the last year of follow-up.

CONCLUSIONS

Shift work in industry is associated with arterial stiffness, reflecting an increased risk of future CVD. No significant changes in arterial stiffness were identified as a consequence of a small reduction in the number of night shifts and consecutive night shifts.

Fatigue and its impact on performance and health

An increasing body of evidence suggests that fatigue among healthcare staff is widespread, owing to a combination of high work intensity, long daytime hours and night-shift working. This has been linked to poorer outcomes for patients and longer inpatient stays, and to increased risks of work-related accidents, errors and injuries for practitioners. These include needlestick injuries and motor vehicle accidents, and other impacts on practitioner health, ranging from cancer, mental health problems, metabolic disorders to coronary disease. Other 24-hour safety-critical industries have fatigue policies that acknowledge the risks of staff fatigue and provide a system to manage it and mitigate harm, but these are still lacking within healthcare. This review explains the basic physiology behind fatigue and outlines its impacts on healthcare practitioners' clinical practice and wellbeing. It proposes methods to minimise these effects for individuals, organisations and the wider UK health service.

Association between medication adherence to chronic diseases and shift-work schedules in the Korean working population

Shift-working schedules are closely linked to chronic diseases, and only a few studies have investigated the association between working schedules and medication adherence in chronic diseases targeting workers. This study aimed to investigate whether shift-work schedules are associated with medication adherence in a working population with chronic conditions. The study participants (n = 11,460 person-years) were identified from the Korea Health Panel Study conducted from 2008 to 2018. Medication adherence was classified as good (2+) or poor (0 or 1) based on the 4-item Morisky Medication Adherence Scale. Work schedules were categorized as shifts and fixed daytime work. Its association with medication adherence was investigated using a generalized estimating equation model, generating odds ratios (OR) with 95% confidence intervals (CI). According to work schedules, shift workers were more likely than fixed-day workers to have poor medication adherence (adjusted OR = 1.16, 95% CI: 1.02-1.33). Regarding occupational classification, manual workers had a significantly higher risk of poor medication adherence than those in other occupational categories (adjusted OR = 1.27, 95% CI: 1.13-1.43). Among shift workers, the major reason for poor medication adherence was forgetting to take medication (SPR = 1.23, 95% CI: 1.07-1.38). Workers with irregular shift times are more vulnerable to poor medication adherence. Future studies are required to understand the mechanisms underlying this association and develop strategies to enhance medication adherence in the working population.

Psychosocial factors and physical activity among workers in Brazil

BACKGROUND

Complex behaviors, such as physical activity (PA), may be related to different levels of influence.

OBJECTIVE

To analyze the role of social support, mood and alcohol consumption as psychosocial predictors on the engagement in PA among Brazilian workers.

METHODS

This is a quantitative, cross-sectional analytical study. A sample of 395 participants answered a sociodemographic questionnaire, the Alcohol Use Disorder Identification Test (AUDIT), the Baecke Habitual Physical Activity Questionnaire, the Social Support Scale for Physical Activities (SSSPA) and the Brunel Mood Scale (BRUMS).

RESULTS

Analysis via Pearson's Correlation Test indicated a negative correlation between PA and depression and fatigue, and a positive correlation between PA and alcohol consumption, vigor and the four variables of social support (support of family members for walking; support of friends for walking; support of family members for moderate and vigorous physical activity; support of friends for moderate and vigorous physical activity). A positive relationship between PA and low-risk alcohol consumption was also identified. A hierarchical multiple regression analysis showed that family support for walking, friends support for moderate and vigorous physical activity, vigor and alcohol consumption are predictors of PA. Hayes' moderation analysis indicated that social support has a moderating effect on the relationship between alcohol use and PA.

CONCLUSION

Different factors may be involved in engaging in PA. A broader approach that addresses the singularities of individuals, especially in actions for different patterns of alcohol consumption, is recommended.

Shift work is significantly and positively associated with possible gastro-esophageal reflux disease: A meta-analysis study

Background

One of the health issues related to shift work patterns is possible gastro-esophageal reflux disease (GERD) symptoms. However, the association between shift work and possible GERD symptoms through meta-analysis has not been developed in the current literature field. Therefore, the purpose of this study is to analyze the association between shift work and possible GERD symptoms through meta-analysis.

Methods

Studies containing target keywords were found in three datasets, and four articles were selected for further analysis after examining the title, abstract, and text. All prevalence odds ratios (ORs) among different groups of the population and the standard error (SE) from each included study were calculated for conducting meta-analysis.

Result

The pooled OR has shown a significant positive association between shift work and possible GERD (OR 1.53; 95% confidence interval [CI] 1.33-1.77, p-value 0.003). Compared to non-shift workers, the subgroup analysis indicates there are positive associations between possible GERD and the night shift (OR 1.39; 95% CI 1.16-1.66), and the rotating shift (OR 1.83; 95% CI 1.44-2.33). The subgroup analysis has also shown similar trends in shift working men (OR 1.28; 95% CI 1.03-1.60) and shift workers of both genders (OR 1.75; 95% CI 1.45-2.11).

Conclusion

This study has shown a positive association between shift work and possible GERD.

What do we know about the effect of night-shift work on cardiovascular risk factors? An umbrella review

Objective

To evaluate the existing evidence on the effect of night-shift work and its subtypes (permanent and rotating) on cardiovascular risk factors: diabetes, lipid disorders, being overweight, hypertension, smoking habits, sedentariness, and occupational psychosocial stressors.

Method

A Web of Sciences and Cochrane review library search was conducted to identify systematic reviews with or without meta-analysis dealing with the quantification of the link between night-shift work and the studied cardiovascular risk factors in working populations. We used the AMSTAR 2 to evaluate the quality of each review. The main results of the included systematic reviews were compiled in a summary structured around the different cardiovascular risk factors.

Results

After selection, 33 systematic reviews were included: nine for diabetes, four for lipid disorders, nine for being overweight, four for hypertension, two for smoking habits, three for occupational psychosocial stressors and two for sedentariness. The results confirmed an excess risk of diabetes of about 10% regardless of the type of night work. A stated excess risk of being overweight at around 25% was also highlighted for shift workers overall, which could reach 38% among night-shift workers. An increased risk of obesity, estimated at 5% for night-shift workers and at 18% for rotating shift workers, was observed. An excess risk of hypertension was estimated at around 30% when considering the broad definition of shift work and when night periods were included in rotating shifts. The literature provided inconsistent results for the link between lipid disorders and night-shift work. Shift workers appeared to be more likely to smoke. The link between shift work and occupational psychosocial stressors was scarcely explored in the available studies. Sedentariness was scarcely considered in systematic reviews, which prevents any firm conclusions.

Conclusion

The consequences of night work in terms of diabetes, being overweight/obesity and hypertension are established. Monitoring of these cardiovascular risk factors for these night-shift workers could be implemented by practitioners. In contrast, the links with lipid disorders, sedentariness, smoking habits, and occupational psychosocial stressors warrant further investigation.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021275212, PROSPERO (ID CRD42021275212).

Association between working evening shifts and mental health among Korean employees: data from the 5th Korean Working Conditions Survey

Background

Many studies have been conducted to investigate the harmful effect of shift work on physical and mental health. Although, by definition, "working evening shift" is included in the scope of shift work, most related studies conducted thus far have focused on working night shifts, overtime work, or different types of shift work, with little research effort dedicated to "working evening shifts." Therefore, to fill this research gap, we investigated the effect of working evening shifts on workers' mental health.

Methods

The participants of this study were 16,692 employees of the 50,205 that participated in the 5^th wave of the Korean Working Conditions Survey. We performed χ² test and logistic regression analysis to analyze the effects of independent variables on health problems and calculated odds ratios and 95% confidence intervals (CIs).

Results

In the logistic regression analysis adjusted for sociodemographic characteristics, health-related factors, and work-related characteristics, employees who worked evening shifts showed higher levels of depression and anxiety compared to those that did not. In particular, the adjusted odds ratios of the group working evening shifts between one and nine times a month were the highest with 2.723 (95% CI: 2.014-3.682) for depression, 3.294 (95% CI: 2.547-4.259) for anxiety.

Conclusions

The results of our study suggest that working evening shifts has a negative effect on employees' mental health. This trend decreased with an increase in the monthly frequency of evening work.

The Time-Varying Effect of Participatory Shift Scheduling on Working Hour Characteristics and Sickness Absence: Evidence from a Quasi-Experiment in Hospitals

Participatory shift scheduling for irregular working hours can influence shift schedules and sickness absence. We investigated the effects of using participatory shift scheduling and shift schedule evaluation tools on working hour characteristics and sickness absence. We utilized a panel data for 2015-2019 with 16,557 hospital employees (6143 in the intervention and 10,345 in the control group). Difference-in-differences regression with ward-level clustered standard errors was used to estimate the average treatment effect on the treated coefficients relative to timing of the intervention with 95% confidence intervals (CI). Using participatory scheduling tool increased long working hours and weekend work and had delayed effects on the short (1-3 days) sickness absences. Increased effects were observed: 0.2 [95% CI 0.0-0.4] days for the second, and 0.8 [95% CI 0.5-1.0] for the third year after the onset of intervention. An average increase of 0.5 [95% CI 0.1-0.9] episodes on all sickness absence episodes was observed for the third year. Using the shift schedule evaluation tool with the participatory shift scheduling tool attenuated the adverse effects. To conclude, participatory shift scheduling increased some potentially harmful working hour characteristics but its effects on sickness absence were negligible, and further attenuated by using the shift schedule evaluation tool.

Time restricted feeding modifies leukocyte responsiveness and improves inflammation outcome

Time restricted eating, the dietary approach limiting food intake to a maximal 10-hour period of daytime is considered beneficial in metabolic dysfunctions, such as obesity and diabetes. Rhythm of food intake and parallel changes in serum nutrient levels are also important entrainment signals for the circadian clock, particularly in tissues involved in metabolic regulation. As both the metabolic state and the circadian clock have large impact on immune functions, we investigated in mice whether time restricted feeding (TRF) affects systemic inflammatory potential. TRF slackened the symptoms in K/BxN serum-transfer arthritis, an experimental model of human autoimmune joint inflammation. Compared to ad libitum conditions TRF reduced the expression of inflammatory mediators in visceral adipose tissue, an integrator and coordinator of metabolic and inflammatory processes. Furthermore, TRF strengthened the oscillation of peripheral leukocyte counts and alongside decreased the pool of both marginated and tissue leukocytes. Our data suggest that the altered leukocyte distribution in TRF mice is related to the attenuated expression of adhesion molecules on the surface of neutrophils and monocytes. We propose that TRF modifies both rhythm and inflammatory potential of leukocytes which contribute to the milder reactivity of the immune system and therefore time-restricted eating could serve as an effective complementary tool in the therapy of autoinflammatory processes.

Association of Shift Work with Normal-Weight Obesity in Community-Dwelling Adults

BACKGRUOUND

Shift work is associated with obesity and metabolic syndrome. However, this association in the normal-weight population remains unclear. This study aimed to investigate whether shift work is associated with normal-weight obesity (NWO).

METHODS

From the nationally representative Korea National Health and Nutrition Examination Survey (KNHANES) dataset (2008 to 2011), 3,800 full-time workers aged ≥19 years with a body mass index (BMI) ≤25 kg/m2 were analysed. We defined NWO as BMI ≤25 kg/m2 and body fat percentage ≥25% in men and ≥37% in women. Working patterns were classified into "daytime," "other than daytime," and "shift." Multivariable logistic regression analysis was performed to evaluate the relationship between shift work and NWO.

RESULTS

Shift work was associated with higher odds of NWO than daytime work (adjusted odds ratio [aOR], 1.47; 95% confidence interval [CI], 1.04 to 2.09) and night/evening work (aOR, 1.87; 95% CI, 1.11 to 3.14) after adjustment for type of work, working hours, age, sex, BMI, 25-hydroxyvitamin D levels, homeostatic model assessment for insulin resistance, and other sociodemographic factors. In subgroup analyses, the association between shift work and NWO was more robust in those aged ≥60 years and those working ≥56 hours/week.

CONCLUSION

Shift work was associated with NWO in community-dwelling Korean adults, independent of age, sex, BMI, and other covariates.

Complex physiology and clinical implications of time-restricted eating

Time-restricted eating (TRE) is a dietary intervention that limits food consumption to a specific time window each day. The effect of TRE on body weight and physiological functions has been extensively studied in rodent models, which have shown considerable therapeutic effects of TRE and important interactions among time of eating, circadian biology, and metabolic homeostasis. In contrast, it is difficult to make firm conclusions regarding the effect of TRE in people because of the heterogeneity in results, TRE regimens, and study populations. In this review, we 1) provide a background of the history of meal consumption in people and the normal physiology of eating and fasting; 2) discuss the interaction between circadian molecular metabolism and TRE; 3) integrate the results of preclinical and clinical studies that evaluated the effects of TRE on body weight and physiological functions; 4) summarize other time-related dietary interventions that have been studied in people; and 4) identify current gaps in knowledge and provide a framework for future research directions.

Night and shift work characteristics and incident ischemic heart disease and atrial fibrillation among healthcare employees - a prospective cohort study

OBJECTIVE

This study aimed to examine the effects of various aspects of night and shift work on the risk of incident ischemic heart disease (IHD) and atrial fibrillation (AF) using detailed and registry-based exposure data.

METHODS

This prospective cohort study included >30 300 healthcare employees (eg, nurses, nursing assistants) employed for at least one year in Region Stockholm 2008-2016. Information on daily working hours was obtained from a computerized administrative employee register and outcomes from national and regional registers. Using discrete-time proportional hazard models, we analyzed the outcomes as functions of working hour characteristics the preceding year, adjusted for sex, age, country of birth, education, and profession.

RESULTS

We observed 223 cases of IHD and 281 cases of AF during follow-up 2009-2016. The risk of IHD was increased among employees who the preceding year had permanent night shifts compared to those with permanent day work [hazard ratio (HR) 1.61, 95% confidence interval (CI) 1.06-2.43] and among employees working night shifts >120 times per year compared to those who never worked night (HR 1.53, 95% CI 1.05-2.21). When restricted to non-night workers, the risk of IHD was increased for employees having frequent quick returns from afternoon shifts. No increased risks were observed for AF.

CONCLUSIONS

Night work, especially working permanent night shifts and frequent night shifts, is associated with an increased risk of incident IHD but not AF. Moreover, frequent quick returns from afternoon shifts (among non-night workers) increased IHD risk. Organizing work schedules to minimize these exposures may reduce IHD risk.

Cohort Profile: The Assessing Economic Transitions (ASSET) Study-A Community-Based Mixed-Methods Study of Economic Engagement among Inner-City Residents

The Assessing Economic Transitions (ASSET) study was established to identify relationships between economic engagement, health and well-being in inner-city populations given that research in this area is currently underdeveloped. This paper describes the objectives, design, and characteristics of the ASSET study cohort, an open prospective cohort which aims to provide data on opportunities for addressing economic engagement in an inner-city drug-using population in Vancouver, Canada. Participants complete interviewer-administered surveys quarterly. A subset of participants complete nested semi-structured qualitative interviews semi-annually. Between April 2019 and May 2022, the study enrolled 257 participants ages 19 years or older (median age: 51; 40% Indigenous, 11.6% non-Indigenous people of colour; 39% cis-gender women, 3.9% transgender, genderqueer, or two-spirit) and 41 qualitative participants. At baseline, all participants reported past daily drug use, with 27% currently using opioids daily, and 20% currently using stimulants daily. In the three months prior to baseline, more participants undertook informal income generation (75%) than formal employment (50%). Employed participants largely had casual jobs (42%) or jobs with part-time/varied hours (35%). Nested qualitative studies will focus on how inner-city populations experience economic engagement. The resulting evidence will inform policy and programmatic initiatives to address socioeconomic drivers of health and well-being.

Ranking the effect of chronodisruption-based biomarkers in reproductive health

Chronodisruption alters circadian rhythms, which has negative consequences on different pathologies and mental disorders. This work studies whether factors related to chronodisruption of circadian rhythms motivated by shift works influence on reproductive health or not. In particular, this influence is studied on four particular aspects related to reproductive health: reproductive health disease, first pregnancy attempt, problems during pregnancy and gestation period. Some explainable machine learning models based on trees have been employed. These methods provided information about the importance of each predictor. The most important variables provided by each method were aggregated using a ranking aggregation function in order to reach a consensus ranking of variables that made possible to understand whether the chronodisruption factors had an effect on each of the aspects studied. The data have been obtained from 697 health professionals. Information about classical biomarkers, sleep quality indices and also other new variables related to eating jet lag, sleep hygiene and how the sleep is affected by shift works were considered as input data. Experiments have shown how some of these novel biomarkers are ranked in the top positions of the issues studied in relation to reproductive health. In particular, the light level and the use of electronic devices, which are features related to chronodisruption, are highlighted as biomarkers.

A systematic review of lifestyle and health among patrolling police officers

BACKGROUND

The police profession is a high-strain and high-risk profession, sometimes resulting in poor physical, mental and social health. This systematic review aims to identify and describe crucial areas for a healthy and sustainable lifestyle among patrolling police officers in Europe, an area not previously studied.

METHODS

The review was conducted according to the PRISMA guidelines. A protocol was published and registered with PROSPERO beforehand. Searches were carried out in eight databases. Two independent authors screened articles and critically appraised the included studies. A narrative synthesis was conducted to analyse the results. The review's total body of evidence was assessed with GRADE-CERQaul.

RESULTS

A total of 16 articles were located, representing 13 studies. Barriers and resources for a healthy and sustainable lifestyle were linked to a theoretical framework of life balance. Subsequently, a linkage model was created to explain different aspects of patrolling police officers' life balance and its relation to health (physical, social and mental).

CONCLUSIONS

Several crucial areas for a healthy and sustainable lifestyle were found and described, indicating that patrolling officers' working life affects their possibilities of living a balanced lifestyle, which might disturb different aspects of health, depending on which aspect is compromised.

Prevalence of elevated blood pressure among locomotive workers according to the long-term assessment of pre-trip health screening

Hypertension is considered as one of the leading cardiovascular diseases in transport workers.

Aim. In the context of epidemiological prospective study, to assess the prevalence of elevated blood pressure (BP) detected at pre-trip health screening (PTHS).

Material and methods. We analyzed records of the database of PTHS automatic system for 15 years (2006-2020) to reveal elevated systolic (140 mm Hg) and/or diastolic (90 mm Hg) BP.

Results. For 15 years, the detection rate of systolic BP >140 mm Hg has decreased by 4 times. For diastolic BP, the detection rate of values >90 mm Hg decreased by 8 times. The detection rate of non-normal systolic BP among railway staff correlates with the detection rate of non-normal diastolic BP (r=0,92; p<0,05) on different railways. Over the 15-year period, the number of suspensions from the trip due to PTHS has decreased by 2 times, while the number of suspensions due to hypertension decreased by 2,5 times.

Conclusion. The conducted study may indicate the effectiveness of primary and secondary prevention of hypertension among Russian Railways staff.

Shift and Night Work and All-Cause and Cause-Specific Mortality: Prospective Results From the STRESSJEM Study

The literature remains sparse and inconclusive about the impact of shift and night work on mortality, and still more on specific causes of death. The objectives were to explore the prospective associations between exposure to shift and night work and all-cause and cause-specific mortality. The study was based on a large national representative French prospective cohort of 1,511,456 employees followed up from 1976 to 2002. Exposure to shift and night work relied on a job-exposure matrix, and 3 time-varying measures (current, cumulative, and recency-weighted cumulative exposure) were constructed. Mortality and causes of death were provided by the national registry, and all-cause, cardiovascular, cancer and preventable mortality, and suicide were studied. Cox proportional hazards models were performed to study the associations between shift and night work and mortality. During follow-up, 22,105 deaths occurred for all-cause mortality. In the study of mortality until the end of last job during follow-up, shift and/or night work were associated with all-cause, cardiovascular, cancer and preventable mortality, and suicide (except night without shift work with cancer mortality and suicide) among men. Shift work (especially shift without night work) was associated with all-cause, cancer and preventable mortality among women. The results were similar for current, cumulative, and recency-weighted cumulative exposure. Associations were found for more detailed causes of death: cerebrovascular diseases for both genders, ischemic heart diseases, respiratory cancers, smoking-related mortality, and external causes of death among men, and breast cancer among women. In the study of mortality until the end of follow-up, some additional associations were found among women between night work and all-cause and preventable mortality, and suicide, suggesting long-term or delayed exposure effects. The study may, however, be underpowered to detect all the exposure-outcome associations, especially among women. More research and prevention are needed to reduce mortality among shift and night workers.

Field-Based Assessments of Behavioral Patterns During Shiftwork in Police Academy Trainees Using Wearable Technology

Circadian misalignment, as occurs in shiftwork, is associated with numerous negative health outcomes. Here, we sought to improve data labeling accuracy from wearable technology using a novel data pre-processing algorithm in 27 police trainees during shiftwork. Secondarily, we explored changes in four metabolic salivary biomarkers of circadian rhythm during shiftwork. Using a two-group observational study design, participants completed in-class training during dayshift for 6 weeks followed by either dayshift or nightshift field-training for 6 weeks. Using our novel algorithm, we imputed labels of circadian misaligned sleep episodes that occurred during daytime, which were previously were mislabeled as non-sleep by Garmin, supported by algorithm performance analysis. We next assessed changes to resting heart rate and sleep regularity index during dayshift versus nightshift field-training. We also examined changes in field-based assessments of salivary cortisol, uric acid, testosterone, and melatonin during dayshift versus nightshift. Compared to dayshift, nightshift workers experienced larger changes to resting heart rate, sleep regularity index (indicating reduced sleep regularity), and alterations in sleep/wake activity patterns accompanied by blunted salivary cortisol. Salivary uric acid and testosterone did not change. These findings show wearable technology combined with specialized data pre-processing can be used to monitor changes in behavioral patterns during shiftwork.

The Influence of Doing Shift Work on the Lifestyle Habits of Primary Care Nurses

Nurses’ lifestyle habits play a key role in promoting healthy lifestyles; although, they may not always be entirely healthy and can be influenced by working conditions. This paper aims to analyze the influence of doing shift work on nurses’ lifestyle habits. Participants (n = 219) were recruited from 27 primary health care centres in Spain. Data were collected on socio-demographic characteristics, working conditions and lifestyle behaviour, assessed by use of an adhoc questionnaire including validated measures. Descriptive analysis and logistic regression models were performed. A total of 95% of the nurses reported having an adequate diet; 45.2% did not engage in any type of physical activity; and 85.8% did not smoke, especially women. A total of 60.3% did shift work, especially the younger ones (80.8%; p < 0.001), these nurses being the ones with the worst food habits (81.8%). In contrast, nurses who did shift work, exercised more days a week (69.5%; p < 0.001). The dietary habits of the nurses were adequate. Low tobacco consumption and low adherence to physical activity were observed, especially among women. Shift work harmed eating habits and obesity rates, but was a protective factor in terms of adherence to physical exercise.

How the reduction of working hours could influence health outcomes: a systematic review of published studies

OBJECTIVES

The health effects of work-time arrangements have been largely studied for long working hours, whereas a lack of knowledge remains regarding the potential health impact of reduced work-time interventions. Therefore, we conducted this review in order to assess the relationships between work-time reduction and health outcomes.

DESIGN

Systematic review of published studies. Medline, PsycINFO, Embase and Web of Science databases were searched from January 2000 up to November 2019.

OUTCOMES

The primary outcome was the impact of reduced working time with retained salary on health effects, interventional and observational studies providing a quantitative analysis of any health-related outcome were included. Studies with qualitative research methods were excluded.

RESULTS

A total of 3876 published articles were identified and 7 studies were selected for the final analysis, all with a longitudinal interventional design. The sample size ranged from 63 participants to 580 workers, mostly from healthcare settings. Two studies assessed a work-time reduction to 6 hours per day; two studies evaluated a weekly work-time reduction of 25%; two studies evaluated simultaneously a reduced weekly work-time reduction proportionally to the amount of time worked and a 2.5 hours of physical activity programme per week instead of work time; one study assessed a reduced weekly work-time reduction from 39 to 30 hours per week. A positive relationship between reduced working hours and working life quality, sleep and stress was observed. It is unclear whether work time reduction determined an improvement in general health outcomes, such as self-perceived health and well-being.

CONCLUSIONS

These findings suggest that the reduction of working hours with retained salary could be an effective workplace intervention for the improvement of employees' well-being, especially regarding stress and sleep. Further studies in different contexts are needed to better evaluate the impact of work-time reduction on other health outcomes.

A scoping review of intermittent fasting, chronobiology, and metabolism

Chronobiology plays a crucial role in modulating many physiologic systems in which there is nutritional synergism with meal timing. Given that intermittent fasting (IF) has grown as a flexible dietary method consisting of delayed or early eating windows, this scoping review addresses the effects of IF protocols on metabolism as they relate to clinical nutrition and the circadian system. Although nocturnal habits are associated with circadian misalignments and impaired cardiometabolic profile-and nutritional physiology is better orchestrated during the day-most findings are based on animal experiments or human studies with observational designs or acute meal tests. Well-controlled randomized clinical trials employing IF protocols of delayed or early eating windows have sometimes demonstrated clinical benefits, such as improved glycemic and lipid profiles, as well as weight loss. However, IF does not appear to be more effective than traditional diets at the group level, and its effects largely depend on energy restriction. Thus, efforts must be made to identify patient biological rhythms, preferences, routines, and medical conditions before individual dietary prescription in clinical practice.

Drivers of professional fulfillment and burnout among emergency medicine faculty: A national wellness survey by the Society for Academic Emergency Medicine

BACKGROUND

Professional fulfillment and the mitigation of burnout can enhance clinician well-being and the resiliency of the health care organization. This study examined the extent to which specific individual and workplace factors are associated with professional fulfillment and burnout among a national sample of academic emergency physicians.

METHODS

This was a cross-sectional survey of faculty members of the Society for Academic Emergency Medicine. Primary outcomes were professional fulfillment and burnout. The survey also examined individual and workplace factors as well as faculty's thoughts of attrition from academic and clinical medicine. Logistic regression was performed to determine the relationships between each outcome and each factor, respectively.

RESULTS

A total of 771 of 3130 faculty completed the survey (response rate 24.6%). A total of 38.7% reported professional fulfillment and 39.1% reported burnout. Meaningfulness of work (odds ratio [OR] 2.2, 95% confidence interval [CI] 1.9-2.5), perceived appreciation (OR 1.9, 95% CI 1.7-2.1), and the academic work environment (OR 1.7, 95% CI 1.5-1.9) had the highest odds of being associated with professional fulfillment. In contrast, low score responses for meaningfulness of work (OR 0.6, 95% CI 0.5-0.6), self-compassion (0.6, 95% CI 0.5-0.6), and control over schedule (OR 0.6, 95% CI 0.6-0.7) were most associated with burnout. Faculty with professional fulfillment were less likely to report plans for attrition from academics (OR 0.1, 95% CI 0.1-0.2) and from clinical medicine (OR 0.2, 95% CI 0.1-0.4). Faculty with burnout were more likely to report plans for attrition from academics (OR 7, 95% CI 4.8-10.4) and clinical medicine (OR 5.7, 95% CI 3.9-8.6).

CONCLUSIONS

Individual and workplace factors that contributed to professional fulfillment and burnout were identified, with meaningfulness of clinical work demonstrating the strongest association with both occupational phenomena. Knowledge of which factors are most impactful in promoting professional fulfillment and mitigating burnout may be useful in guiding efforts to enhance clinician well-being.