Correlates to sleepiness on night shift among male workers engaged in three-shift work in a chemical plant: its association with sleep practice and job stress

Prevalence of Insomnia in Various Industries and Associated Demographic Factors in Night-Shift Workers Using Workers' Specific Health Examination Data

This study aimed to investigate the prevalence of insomnia in various industries and the associated demographic factors. We searched the nationwide night-shift Workers’ Specific Health Examination (nsWSHE) data extracted in 2015 information on factors associated with insomnia, including sex, age, and the number of workers in the workplace. The prevalence of moderate insomnia in the total industry was 4.6%. Industries with a high prevalence of insomnia included the arts, sports, and recreation-related services industry, followed by the activities of household as employers industry, financial and insurance activities industry, human health and social welfare industry, and accommodation and food services activities industry. The prevalence of insomnia was higher in women. Age was a significant factor. In general, insomnia was highest among those aged ≥60 years. Insomnia was highest in small-sized companies with fewer than five employees compared to large enterprises with more than 1000 employees. This study is the first to analyze the prevalence of insomnia among night-shift workers who participated in the WSHEs. The findings of this study can be used to prioritize intervention policies for insomnia among night-shift workers.

Prevalence of current and former smoking in industrial workers worldwide: a systematic review and meta-analysis

OBJECTIVES

One of the health problems in recent decades is the prevalence of smoking in the world. In this study, the global prevalence of smoking in industrial workers was investigated using meta-analysis.

METHOD

The method of the present study was a systematic review and meta-analysis. Three scientific sources, PubMed, Web of Science, and Scopus, were selected for the search, and these databases were searched until September 2020. Random effects method was used for the analysis and then the analysis was performed for the type of smoking (Current, Former), gender, and continent. Heterogeneity was examined in all analyses.

RESULT

A total of 88 studies were included in the meta-analysis. The prevalence of smoking in industrial workers was 41% also the confidence interval was 35-48%. The prevalence of current smoking in industrial workers was 39% also the confidence interval was 29-48%. The prevalence of former smoking in industrial workers was 18% also the confidence interval was 13-22%. I² heterogeneity test was 99.9%.

DISCUSSION

From the findings of the present study, it can be seen that industrial workers are more exposed to smoking compared to the general population, and this can put their health at greater risk.

Relationships between insomnia, long working hours, and long commuting time among public school teachers in Japan: a nationwide cross-sectional diary study

OBJECTIVES

The present study aimed to clarify the prevalence and risk factors of insomnia among public school teachers in Japan by examining the relationships between working hours, commuting time, and insomnia. Time spent on work activities among teachers with insomnia was also investigated.

METHODS

This study was a secondary analysis of data obtained in a 2016 survey of working conditions among public elementary/junior high school teachers in Japan. A total of 11,390 teachers (women: 47.4%, average age: 42.2 ± 11.3 years) were selected for analysis. The relationships between working hours, commuting time, and insomnia were evaluated using a binomial logistic regression model. The primary outcome was insomnia, defined by a score of ≥6 on the Athens Insomnia Scale. Explanatory factors were working hours/week, commuting time/day, six subscales of occupational stress, age group, presence of children, type of job, type of the school, and the urbanicity of the school.

RESULTS

In total, 41.7% of men and 44.0% of women were classified into the insomnia group. The insomnia group spent more time preparing for lectures, and a significant association was observed between insomnia and long working hours and commuting time. Results of multivariate logistic regression analysis showed that long working hours, long commuting time, and urbanicity of the school were statistically significantly associated with insomnia.

CONCLUSIONS

Insomnia is common among public school teachers in Japan. Our findings suggest the importance of reducing the time spent on working to prevent insomnia.

Chronotype, nursing activity, and gender: A systematic review

AIM

To synthesize evidence about the effect of individual circadian preference (chronotype) and gender in the development of sleep and mood problems in nursing professionals.

BACKGROUND

Shift workers are more prone to having unhealthy habits and unfavourable clinical conditions than nonshift workers. These associations are mediated by chronotype and gender differences have also been detected.

DESIGN

A quantitative systematic review.

DATA SOURCES

Electronic searches were performed in MEDLINE, Scopus, ScienceDirect, and Web of Science from 1 July 2012 - 1 July 2017.

REVIEW METHODS

A systematic review was conducted using the Cochrane Collaboration guidelines and two quality assessment tools: the National Heart, Lung and Blood Institute and GRADE. Inclusion criteria were quantitative studies where the sample consists entirely of nurses, analysing circadian rhythms or individual chronotype or gender and sleep/mood disturbances in nursing activity. The review was reported using the PRISMA statement.

RESULTS

A total of 23 studies were included in the review (five cohort studies and 18 cross-sectional studies). Data on gender-specific attention were scarce (two studies) and showed a higher incidence of sleep problems. Female nurses with eveningness-oriented personality seem to be more prone to having sleep disorders, insomnia, fatigue, and anxiety than male and morningness ones.

CONCLUSIONS

Evidence seems to show that female nurses with an evening-oriented preference suffer more problems of insomnia, sleepiness, fatigue, and anxiety. The impact of our results may affect nurses, patient safety and the quality of clinical practice.

Individual vulnerability to insomnia, excessive sleepiness and shift work disorder amongst healthcare shift workers. A systematic review

Shift workers often experience reduced sleep quality, duration and/or excessive sleepiness due to the imposed conflict between work and their circadian system. About 20-30% of shift workers experience prominent insomnia symptoms and excessive daytime sleepiness consistent with the circadian rhythm sleep disorder known as shift work disorder. Individual factors may influence this vulnerability to shift work disorder or sleep-related impairment associated with shift work. This paper was registered with Prospero and was conducted using recommended standards for systematic reviews and meta-analyses. Published literature that measured sleep-related impairment associated with shift work including reduced sleep quality and duration and increased daytime sleepiness amongst healthcare shift workers and explored characteristics associated with individual variability were reviewed. Fifty-eight studies were included. Older age, morning-type, circadian flexibility, being married or having children, increased caffeine intake, higher scores on neuroticism and lower on hardiness were related to a higher risk of sleep-related impairment in response to shift work, whereas physical activity was a protective factor. The review highlights the diverse range of measurement tools used to evaluate the impact of shift work on sleep. Use of standardised and validated tools would enable cross-study comparisons. Longitudinal studies are required to establish causal relationships between individual factors and the development of shift work disorder.

Insomnia in shift work disorder relates to occupational and neurophysiological impairment

STUDY OBJECTIVES

To determine whether occupational and neurophysiological decrements within shift work disorder (SWD) are differentially related to its two diagnostic symptoms, insomnia and excessive sleepiness.

METHODS

Thirty-four permanent night workers participated in an overnight lab protocol including a multiple sleep latency test (MSLT) and an event-related brain potential (ERP) task testing auditory target detection (P3a and P3b). At 16:00, each subject completed an Endicott Work Productivity Scale (EWPS), two Insomnia Severity Indices (ISI-Day, ISI-Night), and an Epworth Sleepiness Scale (ESS). Subjects were grouped by ISI and ESS scores into clinical phenotypes. This study compared EWPS and ERP results between alert insomniacs ("AI," reporting insomnia without sleepiness), sleepy insomniacs ("SI," reporting both insomnia and sleepiness), and controls.

RESULTS

The AI group was most impaired on the EWPS, significantly more impaired than controls (25.8 ± 14.8 vs. 12.3 ± 9.4, p < 0.05). SI were not statistically different from controls (19.5 ± 8.7 vs. 12.3 ± 9.4, p > 0.05). Compared to controls, AI showed significantly attenuated P3a response (Fcz, Czp, Cpz, mean difference [MD] 1.62-1.77, p < 0.05) and target-detection P3b response (Fcz, Czp, Cpz, MD 1.28-1.64, p < 0.05). P3b in SI was not different from controls (p > 0.10), and P3a was only different at one electrode site (Cpz, MD 1.43, p < 0.01). Neither the MSLT nor the ESS correlated with EWPS scores or ERP (P3a/P3b) amplitudes (p > 0.10). However, the mean of the ISI measurements correlated with the EWPS (r = 0.409, p < 0.01) and the attention-to-novelty P3a (r = -0.410, p < 0.01).

CONCLUSIONS

Among shift work disorder patients, insomnia is linked to functional and cognitive impairments. Insomniacs with normal sleepiness showed more severe impairments than insomniacs who also reported excessive sleepiness.

Anti-clockwise rotating shift work and health: would you prefer 3-shift or 4-shift operation?

BACKGROUND

We explored the association between work schedules involving nightshifts and selected measures of health and whether these associations differed among those working in either 3- or 4-shift cycles.

METHODS

Employees at a German industrial company who worked on a fixed daytime schedule or on one involving nightshifts were invited to participate in this cross-sectional study. Work schedules involving a nightshift were organized into either 3 or 4 shifts rotated anti-clockwise on a weekly basis. Health characteristics included a range of clinical and physiological measures and self-reported data on stress and sleep quality. We assessed the independent association of work schedules involving any nightshift and these health characteristics in separate regression analyses, adjusting for age, gender, smoking, and alcohol consumption.

RESULTS

Nightshift work (N = 133) in general and 3-shift-work (N = 53) in particular was associated with decreased sleep quality (P < 0.001). Compared to those working daytime (N = 632), employees working on a 3-shift cycle had higher adjusted odds of meeting the definition of metabolic syndrome (OR = 2.56 [1.38, 4.75]). Employees working 4-shift cycles were somewhat less likely to have metabolic syndrome (OR = 1.22 [0.73, 2.05]) and had higher parasympathetic activity measured by heart rate variability (OR = 2.20 [1.04, 4.63]).

CONCLUSIONS

Our data suggest important relationships between shift schedule and a selected group of objective and subjective health measures. Additional research that further clarifies potential mechanisms underlying these relationships is needed.