Job strain, sleep and alertness in shift working health care professionals -- a field study

The association between shift work disorder and turnover intention among nurses

Background

Shift work disorder (SWD) is highly prevalent among shift-working nurses and has multiple negative health-related effects. There is a dearth of insight into career-related decisions made by nurses suffering from SWD, for instance in terms of their intention to quit work (turnover intention). In this study, we aimed to investigate the association between SWD and turnover intention among nurses, and the individual and work-related correlates of turnover intention.

Method

Data were derived from the ongoing longitudinal cohort study “SUrvey of Shift work, Sleep and Health (SUSSH)” among Norwegian nurses. An annual survey was initiated in 2008/2009 (N = 2965). The present study used data collected in year 2015 (wave 7) and 2016 (wave 8). Nurses were included if: 1) they were working as nurses in both 2015 and 2016, and 2) had completed a three-item scale adapted from the Michigan Organizational Assessment Questionnaire assessing turnover intention (in wave 8), and 3) did not only work day-shifts. SWD was measured in wave 7 with three questions based on the minimal criteria from the third edition of the International Classification of Sleep Disorders. Job demands, decision latitude, and social support at the workplace were measured with subscales of the Swedish Demand-Control-Support Questionnaire.

Results

Eight Hundred eighty-nine nurses were included. The results from the hierarchical linear regression showed that SWD predicted turnover intention one year later, i.e. from 2015 to 2016 (F_1,835 = 6.00, p < 0.05; β = 0.084, p = 0.015). The findings remained significant when controlling for age, sex, organizational tenure, number of nights worked, shift work schedule and workplace social support, job demands and decision latitude.

Conclusion

This study showed that SWD is associated with turnover intention, even when controlling for individual and work-related variables.

Predictors of Shift Work Sleep Disorder Among Nurses During the COVID-19 Pandemic: A Multicenter Cross-Sectional Study

Background: Nurses have a high incidence of shift work sleep disorder, which places their health and patient safety in danger. Thus, exploring the factors associated with shift work sleep disorder in nurses is of great significance in improving their sleep health, nursing personnel staffing, and scheduling during the COVID-19 pandemic.

Objectives: The purpose of this study was to investigate the incidence of shift work sleep disorder during the COVID-19 pandemic and explore the factors associated with shift work sleep disorder in Chinese nurses.

Methods: This was a multicenter cross-sectional study using an online survey. Stratified cluster sampling was used to include 4,275 nurses from 14 hospitals in Shandong, China from December 2020 to June 2021. Stepwise multivariate logistic regression analysis and random forest were used to identify the factors associated with shift work sleep disorder.

Results: The prevalence of shift work sleep disorder in the sampled shift nurses was 48.5% during the COVID-19 pandemic. Physical fatigue, psychological stress, shift work more than 6 months per year, busyness during night shift, working more than 40 h per week, working more than four night shifts per month, sleeping more than 8 h before night shift, using sleep medication, irregular meals, and high-intensity physical activity were associated with increased odds of shift work sleep disorder. Good social support, good work-family balance, napping two or three times per week, resting more than one day after shifts, intervals of 8 days or more between shifts, and taking turns to rest during the night shift were associated with decreased odds of shift work sleep disorder.

Conclusions: Shift work sleep disorder may be associated with scheduling strategies and personal behavior during the COVID-19 pandemic. To reduce the incidence of shift work sleep disorders in nurses, nursing managers should increase night shift staffing, extend rest days after shift, increase night shift spacing, and reduce overtime, and nurses need to seek more family and social support and control their sleep schedules and diet.

Association of job strain with accelerometer-based sleep duration and timing of sleep among older employees

Job strain has been associated with poor sleep quality and could lead to changes in duration and timing of sleep as well. This study examined the association of job strain with sleep duration, bedtimes and awakening times among public sector employees close to their retirement age. Differences in these sleep parameters between workdays and free days across job strain groups were examined. Duration and timing of sleep were measured repeatedly with accelerometers among 466 public sector employees in Finland (mean age 63 years, 86% women), who contributed to 759 measurements in total. Job demands (low/high) and control (low/high) measured by self-reports and job exposure matrix were used to identify low strain (low demand, high control), passive (low, low), active (high, high) and high strain (high, low) jobs. No differences in sleep duration were observed on workdays, whereas on free days those in the high strain group had longer sleep duration than those in the low strain and passive job groups. The high strain group also extended their sleep from workdays to free days more, the extension being on average 59 min (95% CI 42 min-75 min) when adjusted for several sociodemographic, work and health factors. This extension of sleep duration resulted mostly from a greater delay of awakening times from workdays to free days. Psychosocial work factors, such as job strain, need to be considered when promoting sufficient sleep duration among older employees, as those with job strain may have a greater need for recovery and sleep.

Association of rotating shift work schedules and the use of prescribed sleep medication: A prospective cohort study

We examined whether working rotating shifts, with or without night work, is associated with the purchase of prescribed sleep medication, and whether the association is dependent on age. Data were obtained from a longitudinal cohort study of Finnish public sector employees who responded to questions on work schedule and background characteristics in 2000, 2004 and 2008. The data were linked to national register data on redeemed prescriptions of hypnotic and sedative medications, with up to 11 years of follow-up. Age stratified Cox proportional hazard regression models were computed to examine incident use of medication comparing two groups of rotating shift workers (those working shifts that included night shifts and those whose schedules did not include night shifts) with day workers who worked in a similar range of occupations. Shift work with night shifts was associated with increased use of sleep medication in all age groups, after adjustments for sex, occupational status, marital status, alcohol consumption, smoking and physical activity levels (hazard ratio [HR], [95% confidence interval, CI] 1.14 [1.01-1.28] for age group ≤39 years; 1.33 [1.19-1.48] for age group 40-49 years; 1.28 [1.13-1.44] for age group ≥50 years). Shift work without nights was associated with medication use in the two older age groups (HR [95% CI] 1.14 [1.01-1.29] and 1.17 [1.05-1.31] for age groups 40-49 years and >50 years, respectively). These findings suggest that circadian disruption and older age puts rotating shift workers, and especially those who work nights, at increased risk of developing clinically significant levels of sleep problems.

Differences in Daytime Activity Levels and Daytime Sleep Between Night and Day Duty: An Observational Study in Italian Orthopedic Nurses

Working nonstandard work schedules is often associated with increased sedentary behavior and risk of sleep disorders. Night shift workers are prone to accumulating sleep debt, which they recover by sleeping during the day. The effect on daytime activity levels is unknown. The present study aims to objectively assess whether daytime sleep could affect daytime activity levels of shift worker nurses, resulting in an accumulation of their activity debt differently between working and rest periods. The study population (N = 37; mean age 41.7 ± 9.1 years) was composed of orthopedic nurses working on a rotating schedule, including either a night shift (NS) or only day/afternoon shift (DS). Actigraph monitoring lasted both on the working and the rest period. For the NS nurses, the working period recorded higher daytime activity levels than the rest period, while daytime sleep during the working and rest periods was similar. Conversely, DS nurses showed higher daytime activity levels and shorter daytime sleep during the working period. NS nurses were less active than DS nurses during the working period, probably because NS tended to have a longer daytime sleep. During the rest period, daytime activity levels for both groups were decreased. For NS nurses, sleep recorded the better sleep parameters during the rest period, while sleep parameters did not show significant differences between the working and the rest periods in DS. During the working period, NS nurses slept worse than the DS nurses. Both groups tended to accumulate a debt in daytime activity levels during the rest period. While daytime sleep may be an excellent way to counteract sleep debt and increase sleep duration over 24 h period, on the other hand, it makes nurses less active.

Beyond single sleep measures: A composite measure of sleep health and its associations with psychological and physical well-being in adulthood

RATIONALE

Sleep is important for many functions including body and mind restoration. Studies report the association of sleep with stress and physical deterioration, often focusing only on sleep duration; yet, sleep health needs to be understood by multiple dimensions to comprehensively capture its impact on well-being.

OBJECTIVE

This study examined cross-sectional and longitudinal associations of multidimensional sleep health with perceived stress and chronic physical conditions.

METHODS

We used a sample of 441 adults (M age = 57 years) who participated in the biomarker project of the Midlife in the United States Study. Participants provided self-report and actigraphy sleep data in 2004-2009 (T1). We created a composite score of sleep health (Range = 0-6; higher indicating more sleep problems) encompassing: actigraphy-measured regularity, timing, efficiency, duration, and self-reported satisfaction and alertness. Participants responded to the perceived stress scale and chronic physical conditions checklist at T1; chronic physical conditions were reassessed in 2013-2015 (T2).

RESULTS

Cross-sectionally, a composite score of sleep health problems was uniquely associated with higher perceived stress and more chronic conditions, explaining additional variance that each individual sleep variable did not explain. Sleep duration - one of the most commonly researched dimensions of sleep - was not associated with either perceived stress or chronic conditions. Longitudinally, for individuals who had fewer chronic conditions at T1, having more sleep health problems was associated with an increase in chronic conditions at T2. Among the multiple dimensions, sleep satisfaction was most consistently and strongly associated with the outcomes.

CONCLUSION

Findings suggest the importance of considering multiple sleep dimensions concerning psychological and physical well-being in adulthood.

Prevalence of shift work disorder among hospital personnel: A cross-sectional study using objective working hour data

The prevalence of shift work disorder (SWD) has been studied using self-reported data and the International Classification of Sleep Disorders, Second Edition (ICSD-2) criteria. We examined the prevalence in relation to ICSD-2 and ICSD-3 criteria, work schedules and the number of non-day shifts (work outside 06:00-18:00 hours) using objective working-hours data. Secondly, we explored a minimum cut-off for the occurrence of SWD symptoms. Hospital shift workers without (n = 1,813) and with night shifts (n = 2,917) and permanent night workers (n = 84) answered a survey (response rate 69%) on SWD and fatigue on days off. The prevalence of SWD was calculated for groups with ≥1, ≥3, ≥5 and ≥7 monthly non-day shifts utilizing the working hours registry. ICSD-3-based SWD prevalence was 2.5%-3.7% (shift workers without nights), 2.6%-9.5% (shift workers with nights) and 6.0% (permanent night workers), depending on the cut-off of non-day shifts (≥7-1/month, respectively). The ICSD-2-based prevalence was higher: 7.1%-9.2%, 5.6%-33.5% and 16.7%, respectively. The prevalence was significantly higher among shift workers with than those without nights (p-values <.001) when using the cut-offs of ≥1-3 non-day shifts. Shift workers with nights who had ≥3 days with ICSD-3-based SWD symptoms/month more commonly had fatigue on days off (49.3%) than those below the cut-off (35.8%, p < .05). The ICSD-3 criteria provided lower estimates for SWD prevalence than ISCD-2 criteria, similarly to exclusion of employees with the fewest non-day shifts. The results suggest that a plausible cut-off for days with ICSD-3-based SWD symptoms is ≥3/month, resulting in 3%-6% prevalence of SWD.

Decreased psychomotor vigilance of female shift workers after working night shifts

Background

We compared psychomotor vigilance in female shift workers of the Bergmannsheil University Hospital in Bochum, Germany (N = 74, 94% nurses) after day and night shifts.

Methods

Participants performed a 3-minute Psychomotor Vigilance Task (PVT) test bout at the end of two consecutive day and three consecutive night shifts, respectively. Psychomotor vigilance was analyzed with respect to mean reaction time, percentage of lapses and false starts, and throughput as an overall performance score, combining reaction time and error frequencies. We also determined the reaction time coefficient of variation (RTCV) to assess relative reaction time variability after day and night shifts. Further, we examined the influence of shift type (night vs. day) by mixed linear models with associated 95% confidence intervals (CI), adjusted for age, chronotype, study day, season, and the presence of obstructive sleep apnea (OSA).

Results

At the end of a night shift, reaction times were increased (β = 7.64; 95% CI 0.94; 14.35) and the number of lapses higher compared to day shifts (exp(β) = 1.55; 95% CI 1.16–2.08). By contrast, we did not observe differences in the number of false starts between day and night shifts. Throughput was reduced after night shifts (β = -15.52; 95% CI -27.49; -3.46). Reaction times improved across consecutive day and night shifts, whereas the frequency of lapses decreased after the third night. RTCV remained unaffected by both, night shifts and consecutive shift blocks.

Discussion

Our results add to the growing body of literature demonstrating that night-shift work is associated with decreased psychomotor vigilance. As the analysis of RTCV suggests, performance deficits may selectively be driven by few slow reactions at the lower end of the reaction time distribution function. Comparing intra-individual PVT-performances over three consecutive night and two consecutive day shifts, we observed performance improvements after the third night shift. Although a training effect cannot be ruled out, this finding may suggest better adaptation to the night schedule if avoiding fast-changing shift schedules.

Night work and sick leave during pregnancy: a national register-based within-worker cohort study

Objective

The aim of our study was to investigate the acute effect of night work during pregnancy on the risk of calling in sick the following day using register-based information and the workers as their own controls.

Methods

Using the payroll-based national Danish Working Hour Database, including all public hospital employees in Denmark, we identified 9799 pregnant women with ≥1 day shift and ≥1 night shift and ≥1 day of sick leave during the first 32 pregnancy weeks from January 2007 to December 2013. We performed fixed effects logistic regression, that is, within-worker comparisons, of the risk of sick leave of any duration starting within 24 hours after night shifts of different length versus day shifts.

Results

Most of the participants were nurses (64%) or physicians (16%). We found an increased relative risk of sick leave following night shifts compared with day shifts during all pregnancy trimesters. The risk was highest for night shifts lasting >12 hours (OR 1.37, 95% CI 1.15 to 1.63 for nurses; OR 1.87, 95% CI 1.69 to 2.08 for physicians) and among women aged >35 years (OR 1.42, 95% CI 1.24 to 1.63).

Conclusion

Among Danish public hospital employees night shifts during pregnancy, especially shifts longer than 12 hours, increased the risk of calling in sick the following day independent of personal factors and time-invariant confounders in all pregnancy trimesters.

Sleep and alertness in shift work disorder: findings of a field study

Purpose

Although shift work disorder (SWD) affects a major part of the shift working population, little is known about its manifestation in real life. This observational field study aimed to provide a detailed picture of sleep and alertness among shift workers with a questionnaire-based SWD, by comparing them to shift workers without SWD during work shifts and free time.

Methods

SWD was determined by a questionnaire. Questionnaires and 3-week field monitoring, including sleep diaries, actigraphy, the Karolinska Sleepiness Scale (KSS), EEG-based sleep recordings, and Psychomotor Vigilance Tasks (PVT), were used to study 22 SWD cases and 9 non-SWD workers.

Results

The SWD group had a shorter subjective total sleep time and greater sleep debt before morning shifts than the non-SWD group. Unlike the non-SWD group, the SWD group showed little compensatory sleep on days off. The SWD group had lower objective sleep efficiency and longer sleep latency on most days, and reported poorer relaxation at bedtime and sleep quality across all days than the non-SWD group. The SWD group’s average KSS-sleepiness was higher than the non-SWD group’s sleepiness at the beginning and end of morning shifts and at the end of night shifts. The SWD group also had more lapses in PVT at the beginning of night shifts than the non-SWD group.

Conclusions

The results indicate that SWD is related to disturbed sleep and alertness in association with both morning and night shifts, and to less compensatory sleep on days off. SWD seems to particularly associate with the quality of sleep.

Electronic supplementary material

The online version of this article (10.1007/s00420-018-1386-4) contains supplementary material, which is available to authorized users.

Shift work, job strain, and metabolic syndrome: Cross-sectional analysis of ELSA-Brasil

BACKGROUND

Shift work and psychosocial stressors may contribute to higher metabolic syndrome (MetS) incidence. Few studies investigated whether the presence of both factors simultaneously has a synergic effect on risk of MetS.

METHODS

This cross-sectional analysis used baseline data (2008-2010) for 10 960 current workers from ELSA-Brasil. Multiple logistic regression was used to estimate independent associations between shift work and job strain and MetS. An interaction between these factors was tested by including a multiplicative term in the final model.

RESULTS

Exposure to three-shifts a week (that is, three 12 h shifts of work followed by 36 h of rest) and high job-strain were independently associated with greater risk of MetS. We found no indication (P > 0.05) of interaction between working in shifts and job strain on MetS.

CONCLUSIONS

Efforts to reduce job strain and shift work should be considered as part of a primary prevention strategy to reduce the risk of MetS.

An integrative review of the influence of job strain and coping on nurses' work performance: Understanding the gaps in oncology nursing research

Nursing is known to be a stressful profession that can lead to physical and psychological health issues and behavioural problems. In oncology, workload among nurses is believed to be increasing in conjunction with rapidly increasing numbers of patients with cancer and staff shortages worldwide, therefore it is essential to sustain a quality oncology nurse workforce. Numerous studies have presented evidence on job strain, effects of coping strategies, and nurses' work performance within healthcare settings, but few have focused on oncology settings and none of these on nurses working in Saudi Arabia. The purpose of this review was to summarize empirical and theoretical evidence concerning job-related stressors in nurses, particularly oncology nurses, and the interrelationships among job strain, coping strategies, and work performance in this population. Search strategies identified studies published on studies in peer-reviewed journals from 2004 to 2016. Twenty-five nursing studies were found examining the relationships among the concepts of interest. Common job-related stressors among oncology nurses were high job demands, dealing with death/dying, lack of job control, and interpersonal conflicts at work. Job strain was found to be significantly linked to coping strategies, and negatively associated with work performance among nurses in general. There is no existing empirical evidence to support the relationship between coping strategies and work performance among oncology nurses. The present evidence is limited, and a considerable amount of research is required in the future to expand the oncology nursing literature. Research is needed to investigate job-related stressors and their effects on oncology nurses.

Examining self-reported and biological stress and near misses among Emergency Medicine residents: a single-centre cross-sectional assessment in the USA

OBJECTIVES

To examine the relationship between perceived and biological stress and near misses among Emergency Medicine residents.

DESIGN

Self-rated stress and stress biomarkers were assessed in residents in Emergency Medicine before and after a day shift. The supervising physicians and residents reported numbers of near misses.

SETTING

The study took place in the Emergency Department of a large trauma 1 centre, located in Detroit, USA.

PARTICIPANTS

Residents in Emergency Medicine volunteered to participate. The sample consisted of 32 residents, with complete data on 28 subjects. Residents' supervising physicians assessed the clinical performance of each resident.

PRIMARY AND SECONDARY OUTCOME MEASURES

Participants' preshift and postshift stress, biological stress (salivary cortisol, plasma interleukin-6, tumour necrosis factor-alpha (TNF-α) and high-sensitivity C-reactive protein), residents' and supervisors' reports of near misses, number of critically ill and patients with trauma seen during the shift.

RESULTS

Residents' self-reported stress increased from an average preshift level of 2.79 of 10 (SD 1.81) to a postshift level of 5.82 (2.13) (p<0.001). Residents cared for an average of 2.32 (1.52) critically ill patients and 0.68 (1.06) patients with trauma. Residents reported a total of 7 near misses, compared with 11 reported by the supervising physicians. After controlling for baseline work-related exhaustion, residents that cared for more patients with trauma and had higher levels of TNF-α reported a higher frequency of near misses (R²=0.72; p=0.001). Residents' preshift ratings of how stressful they expected the shift to be were related to the supervising physicians' ratings of residents' near misses during the shift.

CONCLUSION

Residents' own ratings of near misses were associated with residents' TNF-α, a biomarker of systemic inflammation and the number of patients with trauma seen during the shift. In contrast, supervisor reports on residents' near misses were related only to the residents' preshift expectations of how stressful the shift would be.

The Effects of a Cluster Randomized Controlled Workplace Intervention on Sleep and Work-Family Conflict Outcomes in an Extended Care Setting

OBJECTIVES

To evaluate the effects of a workplace-based intervention on actigraphic and self-reported sleep outcomes in an extended care setting.

DESIGN

Cluster randomized trial.

SETTING

Extended-care (nursing) facilities.

PARTICIPANTS

US employees and managers at nursing homes. Nursing homes were randomly selected to intervention or control settings.

INTERVENTION

The Work, Family and Health Study developed an intervention aimed at reducing work-family conflict within a 4-month work-family organizational change process. Employees participated in interactive sessions with facilitated discussions, role-playing, and games designed to increase control over work processes and work time. Managers completed training in family-supportive supervision.

MEASUREMENTS

Primary actigraphic outcomes included: total sleep duration, wake after sleep onset, nighttime sleep, variation in nighttime sleep, nap duration, and number of naps. Secondary survey outcomes included work-to-family conflict, sleep insufficiency, insomnia symptoms and sleep quality. Measures were obtained at baseline, 6-months and 12-months post-intervention.

RESULTS

A total of 1,522 employees and 184 managers provided survey data at baseline. Managers and employees in the intervention arm showed no significant difference in sleep outcomes over time compared to control participants. Sleep outcomes were not moderated by work-to-family conflict or presence of children in the household for managers or employees. Age significantly moderated an intervention effect on nighttime sleep among employees (p=0.040), where younger employees benefited more from the intervention.

CONCLUSION

In the context of an extended-care nursing home workplace, the intervention did not significantly alter sleep outcomes in either managers or employees. Moderating effects of age were identified where younger employees' sleep outcomes benefited more from the intervention.

Effects of Shift Work on the Postural and Psychomotor Performance of Night Workers

The purpose of the study was to investigate the effects of shift work on the psychomotor and postural performance of night workers. The study included 20 polysomnography technicians working schedule of 12-h night shift by 36-h off. On the first day of protocol, the body mass and height were measured, and an actigraph was placed on the wrist of each participant. On the second day of protocol, sleepiness by Karolinska Sleepiness Scale, postural control by force platform (30 seconds) and psychomotor performance by Psychomotor Vigilance Task (10 minutes) were measured before and after 12-h night work. Results showed that after 12-h night work, sleepiness increased by 59% (p<0.001), postural control variables increased by 9% (p = 0.048), and 14% (p = 0.006). Mean reaction time, and the number of lapses of attention increased by 13% (p = 0.006) and 425% (p = 0.015), respectively, but the mean reciprocal reaction time decreased by 7%. In addition, there were correlations between sleepiness and postural control variables with opened eyes (r = 0.616, 95% confidence interval [CI] = 0.361-0.815; r = 0.538; 95% CI = 0.280-0.748) and closed eyes (r = 0.557; 95% CI = 0.304-0.764, r = 0497; 95% CI = 0.325-0.715) and a pronounced effect of sleepiness on postural sway (R2 = 0.393; 95% CI = 0.001-0.03). Therefore, 12-h night work system and sleepiness showed a negative impact in postural and psychomotor vigilance performance of night workers. As unexpected, the force platform was feasibility to detect sleepiness in this population, underscoring the possibility of using this method in the workplace to prevent occupational injuries and accidents.

Association of job strain with working hours, shift-dependent perceived workload, sleepiness and recovery

We explored the relationship of job strain with working hours, shift-dependent perceived workload, sleepiness and recovery. Nurses/nursing assistants (n = 95) were recruited from wards that belonged to either the top (high-strain group, HJS) or the bottom (low-strain group, LJS) job strain quartiles of a Job Content Questionnaire survey of employees in five health care districts and four cities in Finland. Three-week field measurements during naturally occurring shift schedules and a subset of pre-selected shift arrangements consisted of the Karolinska Sleepiness Scale, perceived workload and recovery. The HJS group (n = 42) had more single days off and quick returns than the LJS group (n = 53, p < 0.01), and both mental workload and physical workload were rated as higher (p < 0.01). During naturally occurring shift arrangements, severe sleepiness was more common in the HJS group only in quick returns (p = 0.04) and the HJS group recovered on average more poorly from work after all shifts (p = 0.01) and morning shifts (p = 0.02). During pre-selected shift arrangements, the differences between the groups were only minor. In conclusion, job strain-related differences in sleepiness and recovery were mostly attributable to differences in shift arrangements.