Effects of long working hours and the night shift on severe sleepiness among workers with 12-hour shift systems for 5 to 7 consecutive days in the automobile factories of Korea

ObjectiveTo investigate the association between work schedules and motivation for behavioural change of lifestyle, based on the transtheoretical model (TTM) in workers with overweight or obesity.DesignA cross-sectional observational study.SettingA healthcare examination centre in Japan.ParticipantsBetween April 2014 and March 2016, we recruited 9243 participants who underwent healthcare examination and met the inclusion criteria, namely, age 20–65 years, body mass index (BMI) ≥25 kg/m2and full-time workers.ExposureNight and shift (night/shift) workers were compared with daytime workers in terms of motivation for behavioural change.Primary and secondary outcome measuresThe primary outcome was action and maintenance stages of change (SOC) for lifestyle in TTM. In a subgroup analysis, we investigated interactions between characteristics, including age, sex, BMI, current smoking, alcohol habits, hours of sleep and working hours.ResultsOverall, 1390 participants (15.0%) were night/shift workers; night/shift workers were younger (median age (IQR): 46 (40–54) vs 43 (37–52) years) and the proportion of men was lesser (75.4 vs 60.9%) compared with daytime workers. The numbers of daytime and night/shift workers in the action and maintenance SOC were 2113 (26.9%) and 309 (22.2%), respectively. Compared with daytime workers, night/shift workers were less likely to demonstrate action and maintenance SOC (adjusted OR (AOR): 0.85, 95% CI: 0.74 to 0.98). In a subgroup analysis that included only those with long working hours (≥10 hours/day), results revealed a strong inverse association between night/shift work and action and maintenance SOC (AOR: 0.65, 95% CI: 0.48 to 0.86). A significant interaction was observed between long working hours and night/shift work (P for interaction=0.04).ConclusionsIn workers with overweight or obesity, a night/shift work schedule was associated with a lower motivation for behavioural change in lifestyle, and the association was strengthened in those with long working hours.

Download Full-text

Association Night-Shift and Long Working-Hours Effects on Subjective Insomnia in Korean Workers: The Third Korean Working Conditions Survey

The Korean Journal of Health Service Management ◽

10.12811/kshsm.2015.9.1.041 ◽

2015 ◽

Vol 9 (1) ◽

pp. 41-55 ◽

Cited By ~ 1

Author(s):

Chae-Bong Kim ◽

◽

Tae-Young Jung ◽

Seoung-Min Han

Keyword(s):

Working Conditions ◽

Night Shift ◽

Working Hours ◽

Long Working Hours ◽

Korean Working Conditions Survey ◽

The Third

Download Full-text

Night shift work, long working hours and dementia: a longitudinal study of the Danish Work Environment Cohort Study

BMJ Open ◽

10.1136/bmjopen-2018-027027 ◽

2019 ◽

Vol 9 (5) ◽

pp. e027027 ◽

Cited By ~ 5

Author(s):

Kirsten Nabe-Nielsen ◽

Åse Marie Hansen ◽

Kazi Ishtiak-Ahmed ◽

Matias Brødsgaard Grynderup ◽

Finn Gyntelberg ◽

...

Keyword(s):

Risk Factors ◽

Longitudinal Study ◽

Shift Work ◽

Night Shift ◽

Working Hours ◽

Long Working Hours ◽

Night Shift Work ◽

Dementia Risk ◽

Potential Risk Factors ◽

Rate Ratios

ObjectiveShift work and long working hours are potential risk factors for dementia, but previous studies on shift work, long working hours and dementia are sparse and their findings are conflicting. Therefore, we investigated the effect of night shift work and long working hours on dementia.DesignA longitudinal study.SettingDenmark.Participants3435 occupationally active men and women from the general working population.MethodsWork schedule covered day work (reference) and shift schedules without/with night work. Working hours covered <27, 28–36, 37 (reference), 38–44, and ≥45 hours/week. As the primary outcome, we used register-based information about dementia, and estimated incidence rate ratios (IRR) and 95% CI. Estimates were adjusted for gender, age, psychosocial work factors and cardiovascular risk factors.ResultsWe identified 85 dementia cases during a mean of 9.8 years of follow-up. We found a positive, but statistically insignificant association between night shift work and dementia (IRR=2.01; 95% CI: 0.87-4.65). Post hoc analyses indicated that this was only due to a higher risk in permanent night workers (IRR=3.25; 95% CI: 1.35-7.83). The dementia risk was also significantly higher among participants working 38–44 hours/week (IRR=2.08; 95% CI: 1.11-3.90) compared with those working 37 hours/week. We found no indications of a higher risk of dementia in participants working <37 hours/week or ≥45 hours/week.ConclusionWe did not find arguments that night shift work or long working hours increased dementia risk in general. However, we found a higher risk of dementia in specific subgroups, that is, permanent night workers and employees with moderately longer weekly working hours than the standard.

Download Full-text

Prospective Associations Between Working Time Arrangements and Psychiatric Treatment in Denmark: Protocol for a Cohort Study

JMIR Research Protocols ◽

10.2196/18236 ◽

2020 ◽

Vol 9 (6) ◽

pp. e18236 ◽

Cited By ~ 1

Author(s):

Harald Hannerz ◽

Karen Albertsen ◽

Martin Lindhardt Nielsen ◽

Anne Helene Garde

Keyword(s):

At Risk ◽

Psychiatric Hospital ◽

Shift Work ◽

Study Protocol ◽

Night Shift ◽

Working Hours ◽

Incidence Rates ◽

Hospital Treatment ◽

Long Working Hours ◽

Night Shift Work

Background The burden of mental ill health in working-age populations has prompted research on possible links between work-related factors and mental ill health. Long working hours and night shift work are some of the factors that have been studied in relation to the risk of developing mental ill health. Yet, previous studies have not generated conclusive evidence, and further studies of high quality are needed. Objective This study aims to investigate the prospective association between working time arrangements and mental health in terms of psychotropic drug usage or psychiatric hospital treatment in the general working population of Denmark. Methods Data on total weekly working hours in any job and night shift work from the Danish Labor Force Survey 2000–2013 will be linked to data from the Psychiatric Central Research Register (expected 2400 cases during 700,000 person years at risk) and National Prescription Registry (expected 17,400 cases during 600,000 person years at risk). Participants will be followed for up to 5 years. We will use Poisson regression to separately analyze incidence rates of redeemed prescriptions for psychotropic medicine and incidence rates of psychiatric hospital treatment due to mood disorders, anxiety disorders, or stress-related disorders as a function of weekly working hours and night shift work. The analyses will be controlled for sex, age, calendar time of the interview, and socioeconomic status. Results This is a study protocol. Power calculations indicate that the study has sufficient statistical power to detect relatively small differences in risks and minor interactions (eg, ~90% power to detect a rate ratio of 1.1 for psychoactive medication use). We expect the analyses to be completed by the end of 2020 and the results to be published in 2021. Conclusions In this study protocol, all hypotheses and statistical models of the project have been completely defined before we link the exposure data to the outcome data. The results of the project will indicate to what extent and in what direction the national burden of mental ill health in Denmark has been influenced by long working hours and night shift work. International Registered Report Identifier (IRRID) DERR1-10.2196/18236

Download Full-text

Prospective Associations Between Working Time Arrangements and Psychiatric Treatment in Denmark: Protocol for a Cohort Study (Preprint)

10.2196/preprints.18236 ◽

2020 ◽

Author(s):

Harald Hannerz ◽

Karen Albertsen ◽

Martin Lindhardt Nielsen ◽

Anne Helene Garde

Keyword(s):

At Risk ◽

Psychiatric Hospital ◽

Shift Work ◽

Study Protocol ◽

Night Shift ◽

Working Hours ◽

Incidence Rates ◽

Hospital Treatment ◽

Long Working Hours ◽

Night Shift Work

BACKGROUND The burden of mental ill health in working-age populations has prompted research on possible links between work-related factors and mental ill health. Long working hours and night shift work are some of the factors that have been studied in relation to the risk of developing mental ill health. Yet, previous studies have not generated conclusive evidence, and further studies of high quality are needed. OBJECTIVE This study aims to investigate the prospective association between working time arrangements and mental health in terms of psychotropic drug usage or psychiatric hospital treatment in the general working population of Denmark. METHODS Data on total weekly working hours in any job and night shift work from the Danish Labor Force Survey 2000–2013 will be linked to data from the Psychiatric Central Research Register (expected 2400 cases during 700,000 person years at risk) and National Prescription Registry (expected 17,400 cases during 600,000 person years at risk). Participants will be followed for up to 5 years. We will use Poisson regression to separately analyze incidence rates of redeemed prescriptions for psychotropic medicine and incidence rates of psychiatric hospital treatment due to mood disorders, anxiety disorders, or stress-related disorders as a function of weekly working hours and night shift work. The analyses will be controlled for sex, age, calendar time of the interview, and socioeconomic status. RESULTS This is a study protocol. Power calculations indicate that the study has sufficient statistical power to detect relatively small differences in risks and minor interactions (eg, ~90% power to detect a rate ratio of 1.1 for psychoactive medication use). We expect the analyses to be completed by the end of 2020 and the results to be published in 2021. CONCLUSIONS In this study protocol, all hypotheses and statistical models of the project have been completely defined before we link the exposure data to the outcome data. The results of the project will indicate to what extent and in what direction the national burden of mental ill health in Denmark has been influenced by long working hours and night shift work. INTERNATIONAL REGISTERED REPORT DERR1-10.2196/18236

Download Full-text

Long working hours and alcohol use: systematic review and meta-analysis of published studies and unpublished individual participant data

BMJ ◽

10.1136/bmj.g7772 ◽

2015 ◽

Vol 350 (jan12 13) ◽

pp. g7772-g7772 ◽

Cited By ~ 77

Author(s):

M. Virtanen ◽

M. Jokela ◽

S. T. Nyberg ◽

I. E. H. Madsen ◽

T. Lallukka ◽

...

Keyword(s):

Systematic Review ◽

Alcohol Use ◽

Meta Analysis ◽

Working Hours ◽

Individual Participant Data ◽

Long Working Hours ◽

Individual Participant

Download Full-text

Impact of Long Working Hours and Shift Work on Perceived Unmet Dental Need: A Panel Study

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18062939 ◽

2021 ◽

Vol 18 (6) ◽

pp. 2939

Author(s):

Hye-Eun Lee ◽

Nam-Hee Kim ◽

Tae-Won Jang ◽

Ichiro Kawachi

Keyword(s):

Shift Work ◽

Dental Care ◽

Fixed Effects ◽

Panel Study ◽

Working Hours ◽

Care Needs ◽

Long Working Hours ◽

Care Services ◽

Dental Care Needs ◽

Dental Needs

This study investigates whether workers with long working hours as well as shift workers perceive higher unmet dental care needs, and whether there is a gender difference in the associations. We used the Korea Health Panel (2009, 2011–2014) involving 20,451 person-wave observations from 5567 individuals. Perceived unmet dental care needs was defined when the participants reported that they perceived a need for dental treatment or check-up but had failed to receive dental care services during the past year. Fixed effects logit models were applied to examine how changes in weekly working hours or shift work status were linked to changes in perceived unmet dental needs within each individual. Among participants, 15.9–24.7% reported perceived unmet dental needs and the most common reason was time scarcity. We found that long working hours (>52 h/week) was significantly associated with perceived unmet dental needs due to time scarcity in both men (OR = 1.42, 95% CI 1.13–1.78) and women (OR = 1.35, 95% CI 1.03–1.79) compared workers working 40–52 h per week. Shift work was also a significant risk factor, but only in women (OR = 1.57, 95% CI 1.06–2.32). These findings provide evidence for labor policies to reduce working hours in order to improve access to dental care services.

Download Full-text

Impact of Shift Work and Long Working Hours on Worker Cognitive Functions: Current Evidence and Future Research Needs

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18126540 ◽

2021 ◽

Vol 18 (12) ◽

pp. 6540

Author(s):

Veruscka Leso ◽

Luca Fontana ◽

Angela Caturano ◽

Ilaria Vetrani ◽

Mauro Fedele ◽

...

Keyword(s):

Circadian Rhythm ◽

Cognitive Impairment ◽

Sleep Disturbances ◽

Working Hours ◽

Night Work ◽

Current Evidence ◽

Future Research ◽

Negative Effects ◽

Long Working Hours ◽

Main Determinants

Particular working conditions and/or organization of working time may cause important sleep disturbances that have been proposed to be predictive of cognitive decline. In this regard, circadian rhythm misalignment induced by exposure to night work or long working hours would be responsible for cognitive impairment. Nevertheless, evidence supporting this correlation is limited and several issues still need to be elucidated. In this regard, we conducted a systematic review to evaluate the association between shift/night work and cognitive impairment and address its main determinants. Information provided by the reviewed studies suggested that night work might have serious immediate negative effects especially on cognitive domains related to attention, memory and response inhibition. Furthermore, cognitive performance would progressively worsen over consecutive night shifts or following exposure to very long work shifts. Otherwise, conflicting results emerged regarding the possible etiological role that night work chronic exposure would have on cognitive impairment. Therefore, circadian rhythm desynchronization, lack of sleep and fatigue resulting from night work may negatively impact worker’s cognitive efficiency. However, in light of the considerable methodological variability of the reviewed studies, we proposed to develop a standardized research and evaluation strategy in order to obtain a better and comprehensive understanding of this topic.

Download Full-text

A Generalized Structural Equation Model Approach to Long Working Hours and Near-Misses among Healthcare Professionals in Japan

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18137154 ◽

2021 ◽

Vol 18 (13) ◽

pp. 7154

Author(s):

Tatsuhiko Anzai ◽

Takashi Yamauchi ◽

Masaki Ozawa ◽

Kunihiko Takahashi

Keyword(s):

Indirect Effects ◽

Structural Equation ◽

Healthcare Professionals ◽

Sleep Problems ◽

Working Hours ◽

Near Miss ◽

Long Working Hours ◽

Near Misses ◽

Related Stress ◽

Job Related Stress

(1) Background: Near-miss incidents are the foundation of major injuries. They are warning signs that loss is imminent. Long working hours are a risk factor for near-misses along with sleep problems, job-related stress, and depressive symptoms. This study aimed to evaluate the indirect effects of long working hours via mediating variables on near-miss occurrences among Japanese healthcare professionals. (2) Methods: 1490 Japanese healthcare professionals’ reports from a web-based survey of workers in October 2018 were analyzed to evaluate total, direct, and indirect effects of long working hours on near-misses. We applied a generalized structural equation model with three mediating variables: sleep problems, job-related stress, and depressive symptoms. (3) Results: The total effect and direct effect of the categories of working hours longer than 41 h per week (h/w) for occurrence of near-misses were not significantly higher than that of 35–40 h/w. However, for indirect effects on occurrence of near-misses that first passed through job-related stress, there were higher reports for each category compared to 35–40 h/w, with odds ratios (OR) and 95% confidence intervals (95% CI) of OR = 1.12, 95% CI (1.07, 1.21) for 41–50 h/w; 1.25, (1.14, 1.41) for 51–60 h/w; and 1.31, (1.18, 1.51) for ≥ 61 h/w. (4) Conclusion: The results suggest that reducing working hours might improve job-related stress, which could reduce near-misses and prevent injuries.

Download Full-text