Shift schedules and circadian preferences: the association with sleep and mood.

Object: We explored the circadian preferences of non-shift workers (non-SWs) and various types of shift workers (SWs), and the associations of these preferences with sleep and mood. Methods: In total, 4,561 SWs (2,419 women and 2,142 men aged 37.00 ± 9.80 years) and 2,093 non-SWs (1,094 women and 999 men aged 37.80 ± 9.73 years) completed an online survey. Of all SWs, 2,415 (1,079 women and 1,336 men aged 37.77 ± 9.96 years) reported regularly rotating or fixed schedules ("regular SWs"), and 2,146 (1,340 women and 806 men aged 36.12 ± 9.64 years) had irregular schedules ("irregular SWs"). Of the regular SWs, 2,040 had regularly rotating schedules, 212 had fixed evening schedules, and 163 had fixed night schedules. All participants completed the Morningness-Eveningness Questionnaire (MEQ) exploring circadian preferences, the short form of the Center for Epidemiological Studies-Depression Scale (CES-D) evaluating depression, the Insomnia Severity Index (ISI), and the Epworth Sleepiness Scale (ESS). Results: Compared to non-SWs, SWs had lower MEQ scores, i.e., more eveningness, after controlling for age, gender, income, occupation, and weekly work hours (F = 87.97, p < 0.001). Irregular SWs had lower MEQ scores than regular SWs (F = 50.89, p < 0.001). Among regular SWs, the MEQ scores of fixed evening and fixed night SWs were lower than those of regularly rotating SWs (F = 22.42, p < 0.001). An association between the MEQ and ESS scores was apparent in non-SWs (r = -0.85, p < 0.001) but not in SWs (r = 0.001, p = 0.92). Conclusion: SWs exhibited more eveningness than non-SWs; eveningness was particularly prominent in SWs with irregular or fixed evening/night shifts. Eveningness was associated with sleepiness only in non-SWs, but not in SWs.

Decoding the impact of night/day shiftwork on well-being among healthcare workers.

This study delved into the complex effects of work schedules on the well-being of healthcare professionals, spotlighting Nigeria's medical landscape. A diverse cohort of 387 participants, spanning doctors, nurses, pharmacists, and laboratory technicians or scientists, formed the research base, with the majority being women (67.7%), with a mean age of 34.67 years. Professionals self-reported their predominant schedules to gauge work patterns, classifying them as day or night shifts. The World Health Organization Quality of Life Brief Version (WHOQOL-BREF) tool assessed the quality of life across the physical, psychological, social relationship, and environmental domains. Psychological distress was measured using the Depression, Anxiety, and Stress Scales (DASS), and perceived social support was evaluated via the Multidimensional Scale of Perceived Social Support (MSPSS). A cross-sectional design was adopted, and the study employed moderated mediation analysis using SmartPLS 4.0. The results underscored the significant ramifications of night shifts on environmental and physical well-being. Psychological health and social relationships were better among day shift than night shift workers. There was a pronounced correlation between night shifts and heightened levels of anxiety, stress, and depression. The mediating role of psychological distress and the moderating influence of social support in these relationships were evident. This study offers invaluable insights into the role of work schedules in shaping the well-being of healthcare professionals, emphasising the protective role of social support and the unique challenges faced by migrant health workers.

Life satisfaction and job and personal resources among public workers with non-standard work schedules.

BACKGROUND: While the link between non-standard work schedules and poor health outcomes is established, few studies have examined how resources both in and outside of work can support the well-being of workers with non-standard work schedules. METHODS: Using a cross-sectional survey, we assessed the association between one facet of well-being, life satisfaction, and job and personal resources. In 2019, an electronic survey was administered to two unionized, public service populations who work non-standard work schedules: transportation maintainers and correctional supervisors. We assessed life satisfaction with a 10-item scale; a broad set of job resources (reward satisfaction, supervisor support, co-worker support, schedule satisfaction, and working hours fit); and a broad set of personal resources (health status, sleep, physical activity, and finances). We used log-binomial regression models to estimate prevalence ratios and 95% confidence intervals among statistically significant univariate predictors. RESULTS: Of the 316 workers surveyed, the majority were male (86%), White (68%), and reported positive life satisfaction (56%). In multivariate models, the prevalence of positive life satisfaction was higher in workers reporting reward satisfaction (PR:1.35, 95% CI: 1.11, 1.65; p = 0.003), good work schedule fit (PR:1.43, 95% CI: 1.12, 1.83; p = 0.004), good health (PR:2.92, 95% CI: 1.70, 4.99; p < 0.0001), and good finances (PR:1.32, 95% CI: 1.01, 1.72; p = 0.04). CONCLUSION: Employers should consider increasing work recognition, as well as improving schedule fit, financial well-being, and overall good health in support of worker life satisfaction and ultimately well-being.

Work hours, weekend working, nonstandard work schedules and sleep quantity and quality: findings from the UK household longitudinal study.

BACKGROUND: Atypical temporal work patterns such as working longer than the standard 35-40 h/ week, weekend working, and nonstandard work schedules (i.e. outside of the typical 9-5, including but not restricted to shiftwork) are increasingly prevalent in the UK. Aside from occupation-specific studies, little is known about the effects of these atypical temporal work patterns on sleep among workers in the UK, even though poor sleep has been linked to adverse health problems, lower workplace productivity, and economic costs. METHOD: We used regression models to investigate associations between three types of atypical temporal work patterns (long and short weekly work hours, weekend working, and nonstandard schedules) and sleep duration and disturbance using data from over 25,000 employed men and women from 2012-2014 and/or 2015-2017 in the UK Household Longitudinal Study, adjusting for potential confounders and psychosocial work factors. RESULTS: We found that relative to a standard 35-40 h/week, working 55 h/week or more was related to short sleep (less than 7 h/night) and sleep disturbance. Working most/all weekends compared to non-weekends was associated with short sleep, long sleep (more than 8 h/night), and sleep disturbance, as was working nonstandard schedules relative to standard schedules (fixed day-time schedules). Further analyses suggested some gender differences. CONCLUSIONS: These results should prompt employers and policymakers to recognise the need for rest and recovery, consider how the timing and scheduling of work might be improved to better support workers' health and productivity, and consider appropriate compensation for anyone required to work atypical temporal work patterns.

"Multivariate analysis of the impact of sleep and working hours on medical errors: a MICE approach".

BACKGROUND: The main objective of this study was to describe the relationship between working conditions, sleep and psycho-affective variables and medical errors. METHODS: This was an observational, analytical and cross-sectional study in which 661 medical residents answered questionnaires about working conditions, sleep and psycho-affective variables. Actigraphic sleep parameters and peripheral temperature circadian rhythm were measured in a subgroup of 38 subjects. Bivariate and multivariate predictors of medical errors were assessed. RESULTS: Medical residents reported working 66.2 ± 21.9 weekly hours. The longest continuous shift was of 28.4 ± 10.9 h. They reported sleeping 6.1 ± 1.6 h per day, with a sleep debt of 94 ± 129 min in workdays. A high percentage of them reported symptoms related to psycho-affective disorders. The longest continuous shift duration (OR = 1.03 [95% CI, 1.00-1.05], p = 0.01), working more than six monthly on-call shifts (OR = 1.87 [95% CI, 1.16-3.02], p = 0.01) and sleeping less than six hours per working day (OR = 1.66 [95% CI, 1.10-2.51], p = 0.02) were independently associated with self-reported medical errors. The report of medical errors was associated with an increase in the percentage of diurnal sleep (2.2% [95% CI, 0.1-4.3] vs 14.5% [95% CI, 5.9-23.0]; p = 0.01) in the actigraphic recording. CONCLUSIONS: Medical residents have a high working hour load that affect their sleep opportunities, circadian rhythms and psycho-affective health, which are also related to the report of medical errors. These results highlight the importance of implementing multidimensional strategies to improve medical trainees' sleep and wellbeing, increasing in turn their own and patients' safety.

Associations between excessive fatigue and pain, sleep, mental-health and work factors in Norwegian nurses.

AIM: To investigate whether pain, sleep duration, insomnia, sleepiness, work-related factors, anxiety, and depression associate with excessive fatigue in nurses. BACKGROUND: Fatigue among nurses is a problem in the context of ongoing nursing shortages. While myriad factors are associated with fatigue not all relationships are understood. Prior studies have not examined excessive fatigue in the context of pain, sleep, mental health, and work factors in a working population to determine if associations between excessive fatigue and each of these factors remain when adjusting for each other. METHODS: A cross-sectional questionnaire study among 1,335 Norwegian nurses. The questionnaire included measures for fatigue (Chalder Fatigue Questionnaire, score ≥4 categorized as excessive fatigue), pain, sleep duration, insomnia (Bergen Insomnia Scale), daytime sleepiness (Epworth Sleepiness Scale), anxiety and depression (Hospital Anxiety and Depression Scale), and work-related factors. Associations between the exposure variables and excessive fatigue were analyzed using chi-square tests and logistic regression analyses. RESULTS: In the fully adjusted model, significant associations were found between excessive fatigue and pain severity scores for arms/wrists/hands (adjusted OR (aOR) = 1.09, CI = 1.02-1.17), hips/legs/knees/feet (aOR = 1.11, CI = 1.05-1.18), and headaches/migraines (aOR = 1.16, CI = 1.07-1.27), sleep duration of <6 hours (aOR = 2.02, CI = 1.08-3.77), and total symptom scores for insomnia (aOR = 1.05, CI = 1.03-1.08), sleepiness (aOR = 1.11, CI = 1.06-1.17), anxiety (aOR = 1.09, CI = 1.03-1.16), and depression (aOR = 1.24, CI = 1.16-1.33). The musculoskeletal complaint-severity index score (aOR = 1.27, CI = 1.13-1.42) was associated with excessive fatigue in a separate model adjusted for all variables and demographics. Excessive fatigue was also associated with shift work disorder (OR = 2.25, CI = 1.76-2.89) in a model adjusted for demographics. We found no associations with shift work, number of night shifts and number of quick returns (<11 hours between shifts) in the fully adjusted model. CONCLUSION: Excessive fatigue was associated with pain, sleep- and mental health-factors in a fully adjusted model.

Retired night shift workers exhibit poorer neurocognitive function compared to retired day workers.

STUDY OBJECTIVES: Shift work is associated with compromised cognitive function, and with chronic exposure, may place shift workers at elevated risk for dementia. However, evidence of cognitive impairment among former night shift workers is mixed, possibly due to inconsistencies regarding retirement status, work history classification, and cognitive assessments. To address these limitations, this study compared neurocognitive function between retired night shift workers and retired day workers using a well-characterized sample and a rigorous neurocognitive test battery. METHODS: Participants (N = 61; mean age: 67.9 ± 4.7 years; 61% females; 13% non-white) were 31 retired day workers and 30 retired night shift workers equated on age, sex, race/ethnicity, premorbid IQ, years retired, and diary-assessed habitual sleep characteristics. Participants completed a neurocognitive battery assessing six cognitive domains (language, visuospatial ability, attention, immediate and delayed memory, executive function) and self-reported cognitive function. Linear regression models compared groups on individual cognitive domains, adjusting for age, sex, race/ethnicity, education level, and habitual sleep quality. RESULTS: Retired night shift workers scored lower than retired day workers on attention (B = -0.38, 95% CI [-0.75, -0.02], p = .040) and executive function (B = -0.55, 95% CI [-0.92, -0.17], p = .005). In post hoc analyses, attention and executive function were unrelated to diary-assessed habitual sleep characteristics (disruption, timing, and irregularity) in retired night shift workers. CONCLUSIONS: The observed cognitive weaknesses in retired night shift workers may suggest increased risk for future dementia. Retired night shift workers should be followed to determine whether observed weaknesses progress.

Sleep in Residents: A Comparison between Anesthesiology and Occupational Medicine Interns.

Sleep deprivation is a significant risk to the health and judgment of physicians. We wanted to investigate whether anesthesiology residents (ARs) who work only one night shift per week have different physical and mental health from occupational medicine residents (OMRs) who do not work at night. A total of 21 ARs and 16 OMRs attending a university general hospital were asked to wear an actigraph to record sleep duration, heart rate and step count and to complete a questionnaire for the assessment of sleep quality, sleepiness, fatigue, occupational stress, anxiety, depression and happiness. ARs had shorter sleep duration than OMRs; on average, they slept 1 h and 20 min less (p < 0.001). ARs also had greater daytime sleepiness, a higher heart rate and lower happiness than OMRs. These results should be interpreted with caution given the cross-sectional nature of the study and the small sample size, but they are an incentive to promote sleep hygiene among residents.

Shift Work and Sleep Disturbance in the Oil Industry.

BACKGROUND: Rotating shift work is common in high-hazard industries, despite documented associations with sleep disturbance and impairment. In the oil industry, where rotating and extended shift schedules are used to staff safety-sensitive positions, work intensification and increasing overtime rates have been broadly documented over the last few decades. Research on the impacts of these work schedules on sleep and health has been limited for this workforce. METHODS: We examined sleep duration and quality among rotating shift workers in the oil industry and explored associations between schedule characteristics, sleep, and health outcomes. We recruited hourly refinery workers from the West and Gulf Coast oil sector members of the United Steelworkers union. FINDINGS: Impaired sleep quality and short sleep durations were common and associated with health and mental health outcomes common among shift workers. Shortest sleep durations followed shift rotations. Early rise and start times were associated with shorter sleep duration and poorer sleep quality. Drowsiness and fatigue-related incidents were common. CONCLUSION/APPLICATION TO PRACTICE: We observed lower sleep duration and quality and increased overtime in 12-hour rotating shift schedules. These long workdays with early start times may reduce available hours for quality sleep; here they were associated with reduced exercise and leisure activity which correlated with good sleep. This safety-sensitive population appears severely impacted by poor sleep quality, which has broader implications for process safety management. Later start times, slower rotation, and a reconsideration of two-shift schedules are interventions to consider for improving sleep quality among rotating shift workers.

Evaluation of work conditions of nurses employed in a shift system in hospital wards during the COVID-19 pandemic.

BACKGROUND: Nurses work in a shift system that determines the provision of round-the-clock care of a patient in hospital conditions; however, it entails health consequences. OBJECTIVE: The aim of the study was the evaluation of work conditions of nurses engaged in shift work in hospital wards during the COVID-19 pandemic. METHODS: The study was conducted in 2020, and included 108 nurses working in a shift system in hospital wards. The research method was a diagnostic survey, using an author-constructed questionnaire. RESULTS: 88.9% nurses reported a negative effect of shift work on their physical health: 'musculoskeletal pain', 'elevated arterial blood pressure', and 'hormonal disorders' - 54.5% of respondents used pharmacological treatment. The causes of physical disorders were: 'microclimate', 'physical effort', 'noise', and 'forced body position'. Shift work exerted a negative effect on psychological health of the majority of respondents (75.0%): 'deconcentration', 'sleep disorders', 'feeling of occupational burnout' - treatment in 38.9% of respondents. Psychological health disorders were caused by: 'circadian rhythms disturbance by shift work', 'chronic stresses', and 'conflicts at work'. 69.7% of respondents reported that their shift work was disturbed by organizational factors, including: a 'badly planned work schedule', 'enhanced pace of work due to staff shortage', 'ambiguous division of duties, rights, responsibilities', 'shortages of equipment at the workplace'. CONCLUSION: The examined nurses experienced a negative effect of shift work on their physical and psychological health which, for some of them, was the cause of pharmacological treatment. Many organizational factors hindered the work of nurses in a shift system in hospital wards.

Improving performance on night shift: a study of resident sleep strategies.

STUDY OBJECTIVES: To identify sleep strategies of internal medicine residents transitioning to night shift and report their effect on performance. METHODS: Residents logged hours of sleep and work starting 3 days prior to the first night shift and continuing through the next 8 days. Cohorts were defined by sleep logs and compared separately by transition strategy, total hours of sleep, amount of sleep occurring at work, weekend sleep schedule, and residency training year. Data from logs were entered into the Fatigue Avoidance Scheduling Tool to measure predicted Performance Effectiveness (PE) during each night shift. RESULTS: Twenty-three residents were evaluated. The Sleep Banking transition strategy (n = 2) had higher PE (mean = 88.6%) than all other sleep strategies combined (n = 21, mean = 80.9%; P = .016). Additionally, residents who slept an average of 8-9 hours daily during their week of night shifts had a higher mean PE compared to those who slept < 6 hours (86.8% vs 78.6%; P = .014). CONCLUSIONS: Residents who engaged in Sleep Banking prior to the first night shift had higher PE and spent less time above a 0.05% blood alcohol concentration equivalent compared to all other strategies. Similarly, PE and time spent above a 0.05% blood alcohol concentration equivalent improved with increased average hours slept per day during the week of night shifts. Optimizing performance on night shift through the adoption of efficacious sleep strategies is imperative to mitigate patient safety issues that may result from poor alertness and cognitive abilities. CITATION: Cushman P, Scheuller HS, Cushman J, Markert RJ. Improving performance on night shift: a study of resident sleep strategies. J Clin Sleep Med. 2023;19(5):935-940.

Mental health risk factors for shift work disorder in paramedics: A longitudinal study.

OBJECTIVES: Depression and anxiety are prominent in paramedics, as is the prevalence of shift work disorder (SWD), a circadian sleep condition comorbid with mental health disorders. However, the role of mental health risk factors for SWD is largely unknown. This study investigated whether mental health levels in recruit paramedics before shift work predicted greater risk of SWD at 6-months into their career and explored whether shift and sleep factors mediated this relationship. DESIGN: A longitudinal study. SETTING: Victoria, Australia. PARTICIPANTS: Recruit paramedics were assessed at baseline (n = 101; ie, pre-shift work) and after 6-months (n = 93) of shift and emergency work. MEASUREMENTS: At both time points, participants completed self-reported measures of depression (Patient Health Questionnaire-9), anxiety (Generalized Anxiety Disorder Questionnaire-7), and SWD (SWD-Screening Questionnaire). Participants also filled a sleep and work diary for 14-days at each timepoint. RESULTS: After 6-months of emergency work 21.5% of paramedics had a high SWD risk. Logistic regression models showed baseline depression predicted 1.24-times greater odds for SWD at 6-months. Through Lavaan path analysis we found shift and sleep variables did not mediate the relationship between baseline mental health and SWD risk. Baseline depression was associated with increased sleepiness levels following paramedics' major sleep periods at 6-months. Pre-existing depression levels also predicted greater perceived nightshift workload. CONCLUSIONS: Our results highlight depression symptoms before emergency work are a risk factor for SWD within 6-months of work. Depression represents a modifiable risk factor amenable to early interventions to reduce paramedics' risk of SWD.

The Effect of Night Float Rotation on Resident Sleep, Activity, and Well-Being.

BACKGROUND: Night float call systems are becoming increasingly common at training programs with the goal of reducing fatigue related to sleep deprivation and sleep disturbance. Previous studies have shown that trainees obtain less sleep during the night float rotation and have decreased sleep efficiency for several days after the rotation. The impact on physical and emotional well-being has not been documented. METHODS: Twenty-seven anesthesia residents were enrolled in a study using wearable sleep and activity trackers and National Institutes of Health Patient-Reported Outcome Measurement Information System (NIH PROMIS) surveys for sleep disturbance, fatigue, and positive affect to record data the week before ("baseline"), during ("night float"), and 1 week after ("recovery") their night float rotation. Each subject's data during the night float week and recovery week were compared to his or her own baseline week data using a paired, nonparametric analysis. The primary outcome variable was the change in average daily sleep hours during the night float week compared to the baseline week. Average daily rapid eye movement (REM) sleep, daily steps, and NIH PROMIS scores comparing night float and recovery weeks to baseline week were prespecified secondary outcomes. NIH PROMIS scores range from 0 to 100 with 50 as the national mean and more of the construct having a higher score. RESULTS: There was no difference in average daily sleep hours between the night float and the baseline weeks (6.7 [5.9-7.8] vs 6.7 [5.5-7.7] hours, median [interquartile range]; P = .20). Residents had less REM sleep during the night float compared to the baseline weeks (1.1 [0.7-1.5] vs 1.4 [1.1-1.9] hours, P = .002). NIH PROMIS fatigue scores were higher during the night float than the baseline week (58.8 [54.6-65.1] vs 48.6 [46.0-55.1], P = .0004) and did not return to baseline during the recovery week (51.0 [48.6-58.8], P = .029 compared to baseline). Sleep disturbance was not different among the weeks. Positive affect was reduced after night float compared to baseline (39.6 [35.0-43.5] vs 44.8 [40.1-49.6], P = .0009), but returned to baseline during the recovery week (43.6 [39.6-48.2], P = .38). CONCLUSIONS: The residents slept the same number of total hours during their night float week but had less REM sleep, were more fatigued, and had less positive affect. All of these resolved to baseline except fatigue, that was still greater than the baseline week. This methodology appears to robustly capture psychophysiological data that might be useful for quality initiatives.

Daytime eating prevents mood vulnerability in night work.

Shift workers have a 25 to 40% higher risk of depression and anxiety partly due to a misalignment between the central circadian clock and daily environmental/behavioral cycles that may negatively affect mood and emotional well-being. Hence, evidence-based circadian interventions are required to prevent mood vulnerability in shift work settings. We used a stringently controlled 14-d circadian paradigm to assess mood vulnerability during simulated night work with either daytime and nighttime or daytime-only eating as compared with simulated day work (baseline). Simulated night work with daytime and nighttime eating increased depression-like mood levels by 26.2% (p-value adjusted using False Discovery Rates, pFDR = 0.001; effect-size r = 0.78) and anxiety-like mood levels by 16.1% (pFDR = 0.001; effect-size r = 0.47) compared to baseline, whereas this did not occur with simulated night work in the daytime-only eating group. Importantly, a larger degree of internal circadian misalignment was robustly associated with more depression-like (r = 0.77; P = 0.001) and anxiety-like (r = 0.67; P = 0.002) mood levels during simulated night work. These findings offer a proof-of-concept demonstration of an evidence-based meal timing intervention that may prevent mood vulnerability in shift work settings. Future studies are required to establish if changes in meal timing can prevent mood vulnerability in night workers.

Effects of Factors Related to Shift Work on Depression and Anxiety in Nurses.

Background: Although shift work is the foundation of the provision of 24-h continuous care in hospitals, it can negatively impact mental health in hospital workers such as nurses. Despite the connection between mental health and overall health, little is known about the effect of shift work-related factors on mental health in this population. Objectives: We investigated the effect of scheduling practices, physical and psychological characteristics related to shift work, and personal habits during shift work on depression and anxiety among nurses. Methods: In this multi-center cross-sectional study, 11,061 nurses from 20 hospitals in the Shandong Province of China completed an online survey between December 2020 and February 2022. Multivariate ordered logistic regression analysis was performed to examine shift-related factors associated with depression and anxiety in the study population. Results: The completion rate of all nurses' questionnaires was 83.00% (n = 9,181). Among the 9,181 respondents, 66.20% (n = 6,078) were shift nurses. Depression and anxiety were found in 58.82 and 62.08% of shift nurses, respectively, and these rates were influenced by fatigue during shift work, psychological stress before/during/after night shifts, feeling of being refreshed after resting before/after night shifts, using sleep medication before/after night shifts, physical discomfort during night shifts, busyness during night shifts, food intake during shift work, working > 40 h/week during shift work, and sleep quality before/after night shifts. Conclusions: Depression and anxiety in shift nurses may be addressed by reducing their workload, sources of stress during night shifts, and facilitating rest and relaxation.

On-call-related sleep deprivation and hypomania in healthcare workers.

OBJECTIVE: Acute sleep deprivation can induce antidepressant effects. We hypothesized that overnight calls can trigger symptoms of hypomania during the post-on-call period. METHODS: Online anonymous cross-sectional survey among Spanish-speaking healthcare professionals, including the Hypomania Symptom Checklist-32 (HCL-32). RESULTS: 2099 respondents. Most of them reported that they usually feel worse on their post-on-call period (91,3%), but the 51,6% acknowledged having felt better at least once and 33,4% reported it happened in at least at 50% of their calls. Up to 4,9% reached the cut-off at HCL-32. Males, younger professionals, those with less years of practice and residents were more likely to full fit hypomania criteria. Participants and their environment correctly identified the symptoms and their negative consequences. CONCLUSIONS: On-calls with sleep deprivation may trigger hypomanic symptoms with reported negative consequences among healthcare professionals, showing how working conditions' impact in professionals' wellbeing and raising concerns about decision-making performance after long-lasting working shifts.

Factors Associated with Gastrointestinal Symptoms among Rotating Shift Nurses in South Korea: A Cross-Sectional Study.

Rotating shift work places a serious burden on nurses' physical and psychological health. Gastrointestinal (GI) symptoms are a common complaint among shift workers. This study assessed GI symptoms and identified the associations between dietary habits, psychological status, and sleep quality among rotating shift nurses. Data from 125 female nurses in rotating shifts who worked at two tertiary hospitals in South Korea were collected using a questionnaire that included the Gastrointestinal Symptoms Questionnaire; the Dietary Habit Questionnaire; the Depression, Anxiety, Stress Scale (DASS)-21; and the Pittsburgh Sleep Quality Index (PSQI). All participants experienced various GI symptoms, and 47% of them complained of at least one severe GI symptom. There were significant differences in GI symptom scores according to the status of depression, anxiety, stress, and sleep quality. In multiple linear regression analysis, the factors associated with an increase in the occurrence and severity of GI symptoms were poor sleep quality and morbid anxiety and stress. The model explained power at 43.2%. As most nurses in rotating shifts experience GI symptoms, they should receive counseling and training programs at work to alleviate psychological symptoms, improve sleep quality, and pay more attention to their health status as well as GI symptom management.

Long Working Hours Indirectly Affect Psychosomatic Stress Responses via Complete Mediation by Irregular Mealtimes and Shortened Sleep Duration: A Cross-Sectional Study.

BACKGROUND: Long working hours are detrimental to physical and mental health. However, the association between long working hours and psychosomatic symptoms have remained controversial, possibly because of the existence of mediators between working hours and psychosomatic stress responses. We hypothesized that lifestyle habits, regarding sleep and mealtimes, act as mediators, and analyzed the associations between long working hours, sleep duration, mealtime regularity, and psychosomatic stress responses in office workers. METHODS: From April 2017 to March 2018, an online cross-sectional survey regarding overtime work hours, work-related stress, sleep, and eating habits was conducted with employees of 17 companies located in Tokyo, Japan. Answers were obtained from 3559 employees, and 3100 provided written consent for the academic use of their answers, and were included in the analysis. A path analysis was conducted to assess the effect of overtime work on psychosomatic stress via shortened sleep or irregular mealtimes. RESULTS: Overtime work hours had no direct effect on psychosomatic stress responses and depressive symptoms. However, overtime work hours affected sleep duration and the regularity of mealtimes. The effects of overtime work hours on psychosomatic stress responses and depressive symptoms were completely mediated by sleep duration and the regularity of mealtimes. CONCLUSION: Long working hours do not affect mental health directly; however, shortened sleep duration and irregular mealtimes mediate the effect of long working hours on psychosomatic stress responses and depressive symptoms.

Shift Work Disorder Index: initial validation and psychosocial associations in a sample of nurses.

STUDY OBJECTIVES: Shift work is common yet does not always result in Diagnostic and Statistical Manual of Mental Disorders, fifth edition (DSM-5)-defined shift work sleep disorder (SWD). This study reports on the reliability and validity of the DSM-5 informed Shift Work Disorder Index (SWDI), the presence of probable SWD in nurses, and demographic, sleep, and psychosocial correlates. METHODS: Nurses (n = 454) completed the SWDI, psychosocial, and demographic questionnaires. Of the sample, n = 400 completed 14 days of sleep diaries, actigraphy, and additional questionnaires. RESULTS: The global SWDI demonstrated excellent internal consistency (α = .94), as well as good convergent and divergent validity in the nurse sample. Thirty-one percent of nurses were past-month shift workers, with 14% (ie, 44% of shift workers) having probable SWD based on SWDI. Nurses who worked shift work and/or met SWD criteria were more likely to be younger and unmarried and less likely to have children than day workers and reported greater evening chronotype, insomnia, nightmares, and sleep-related impairment, greater depression, anxiety, posttraumatic stress, and perceived stress symptoms, as well as later and more variable sleep midpoint (actigraphy), shorter sleep duration (actigraphy, diaries), and lower sleep efficiency (diaries). CONCLUSIONS: The SWDI is an efficient and valid self-report assessment of DSM-5-defined SWD. Shift work and/or SWD were prevalent and associated with worse sleep and psychosocial health, particularly among nurses with probable SWD. CITATION: Taylor DJ, Dietch JR, Wardle-Pinkston S, et al. Shift Work Disorder Index: initial validation and psychosocial associations in a sample of nurses. J Clin Sleep Med. 2022;18(10):2339-2351.