The role of compensation in explaining harmful effects of overtime work on self-reported heart disease: Preliminary evidence from a Germany prospective cohort study

Association of Occupational and Leisure-Time Physical Activity With Allostatic Load

INTRODUCTION

Leisure-time physical activity decreases allostatic load, a measure of burden of chronic stress. However, the role of occupational physical activity is unknown. This study examined associations of occupational physical activity and leisure-time physical activity with allostatic load among workers in the U.S.

METHODS

This cross-sectional study included 6,944 U.S. workers aged 20-64 years from the National Health and Nutrition Examination Survey (2007-2018). Physical activity was assessed using the Global Physical Activity Questionnaire. Allostatic load was calculated using biomarkers of cardiovascular, metabolic, and immune systems. Associations of occupational physical activity and leisure-time physical activity with allostatic load were examined using negative binomial regressions. Analyses were conducted between August 2022 and March 2023.

RESULTS

Vigorous leisure-time physical activity inversely associated with allostatic load among all workers (count ratio=0.68, 95% CI=0.62, 0.76) and in each sex- and age-stratified group as well as in each race/ethnicity-stratified group. Vigorous occupational physical activity positively associated with allostatic load only among females aged 20-44 years (1.38, 95% CI=1.10, 1.73). Inverse associations of vigorous leisure-time physical activity with allostatic load were similar in young females with high or low vigorous occupational physical activity.

CONCLUSIONS

Increasing vigorous leisure-time physical activity associates with a lower allostatic load for all workers, whereas increasing vigorous occupational physical activity associates with a higher allostatic load only in young females. Promoting vigorous leisure-time physical activity reduces allostatic load among young females with either low or high vigorous occupational physical activity.

Long working hours and cardiovascular diseases, time for preventive action

The effects of long working hours, night and shift work on cardiovascular diseases, have been found in different populations around the world. The aim is to emphasize the importance of appropriate action in relation to the association of long working hours with cardiovascular disease. It is time to improve working conditions and health promotion and wellness programmes. Occupational researchers/practitioners have a major role to play in promoting these next steps and potential interventions.

Unpaid overtime and mental health in the Canadian working population

BACKGROUND

Unpaid overtime-describing a situation where extra hours are worked but not paid for-is a common feature of the labor market that, together with other forms of wage theft, costs workers billions of dollars annually. In this study, we examine the association between unpaid overtime and mental health in the Canadian working population. We also assess the relative strength of that association by comparing it against those of other broadly recognized work stressors.

METHODS

Data were drawn from a survey administered to a heterogeneous sample of workers in Canada (n = 3691). Generalized linear models quantified associations between unpaid overtime, stress, and burnout, distinguishing between moderate (1-5) and excessive (6 or more) hours of unpaid overtime.

RESULTS

Unpaid overtime was associated with higher levels of stress and burnout. Relative to those working no unpaid overtime, men working excessive unpaid overtime were 85% more likely to report stress (prevalence ratios [PR]: 1.85, 95% confidence interval [CI]: 1.26-2.72) and 84% more likely to report burnout (PR: 1.84, 95% CI: 1.34-2.54), while women working excessive unpaid overtime were 90% more likely to report stress (PR: 1.90, 95% CI: 1.32-2.75) and 52% more likely to report burnout (PR: 1.52; 95% CI: 1.12-2.06). The association of excessive unpaid overtime with mental health was comparable in magnitude to that of shift work and low job control.

CONCLUSIONS

Unpaid overtime may present a significant challenge to the mental health of working people, highlighting the potential role of wage theft as a neglected occupational health hazard.

Overtime work and Chinese workers' physical and mental health: The mediating role of social support and work value awareness

BACKGROUND

China was once called the world's factory. Chinese workers had long weekly working hours. However, the empirical results of the relationship between overtime work and workers' health are mixed and remain inconclusive.

OBJECTIVE

This study aimed to investigate how overtime work influenced workers' physical and mental health and the role of lifestyles, social support, and work value awareness.

METHODS

Data from the China Labor-force Dynamics Survey 2016 (N = 14,205) was used. The instrumental variable approach was employed to overcome the endogeneity problem between overtime work and workers' health. The bootstrapping method was conducted to elicit the role of lifestyles, social support, and work value awareness.

RESULTS

The results indicated that overtime work significantly and negatively influenced Chinese workers' physical and mental health. The results of the bootstrapping suggested that workers' social support and work value awareness partially mediated the relationship between overtime work and their physical and mental health. However, the mediating role of lifestyles was insignificant.

CONCLUSION

Through using big data with national representativeness, this study suggests that overtime work negatively influences Chinese workers' physical and mental health. Our findings provide policy implications for improving workers' health rights and well-being in emerging economies.

The effect of exposure to long working hours on ischaemic heart disease: A systematic review and meta-analysis from the WHO/ILO Joint Estimates of the Work-related Burden of Disease and Injury

BACKGROUND

The World Health Organization (WHO) and the International Labour Organization (ILO) are developing Joint Estimates of the work-related burden of disease and injury (WHO/ILO Joint Estimates), with contributions from a large network of experts. Evidence from mechanistic data suggests that exposure to long working hours may cause ischaemic heart disease (IHD). In this paper, we present a systematic review and meta-analysis of parameters for estimating the number of deaths and disability-adjusted life years from IHD that are attributable to exposure to long working hours, for the development of the WHO/ILO Joint Estimates.

OBJECTIVES

We aimed to systematically review and meta-analyse estimates of the effect of exposure to long working hours (three categories: 41-48, 49-54 and ≥55 h/week), compared with exposure to standard working hours (35-40 h/week), on IHD (three outcomes: prevalence, incidence and mortality).

DATA SOURCES

We developed and published a protocol, applying the Navigation Guide as an organizing systematic review framework where feasible. We searched electronic databases for potentially relevant records from published and unpublished studies, including MEDLINE, Scopus, Web of Science, CISDOC, PsycINFO, and WHO ICTRP. We also searched grey literature databases, Internet search engines and organizational websites; hand-searched reference lists of previous systematic reviews; and consulted additional experts.

STUDY ELIGIBILITY AND CRITERIA

We included working-age (≥15 years) workers in the formal and informal economy in any WHO and/or ILO Member State but excluded children (aged < 15 years) and unpaid domestic workers. We included randomized controlled trials, cohort studies, case-control studies and other non-randomized intervention studies which contained an estimate of the effect of exposure to long working hours (41-48, 49-54 and ≥55 h/week), compared with exposure to standard working hours (35-40 h/week), on IHD (prevalence, incidence or mortality).

STUDY APPRAISAL AND SYNTHESIS METHODS

At least two review authors independently screened titles and abstracts against the eligibility criteria at a first stage and full texts of potentially eligible records at a second stage, followed by extraction of data from qualifying studies. Missing data were requested from principal study authors. We combined relative risks using random-effect meta-analysis. Two or more review authors assessed the risk of bias, quality of evidence and strength of evidence, using Navigation Guide and GRADE tools and approaches adapted to this project.

RESULTS

Thirty-seven studies (26 prospective cohort studies and 11 case-control studies) met the inclusion criteria, comprising a total of 768,751 participants (310,954 females) in 13 countries in three WHO regions (Americas, Europe and Western Pacific). The exposure was measured using self-reports in all studies, and the outcome was assessed with administrative health records (30 studies) or self-reported physician diagnosis (7 studies). The outcome was defined as incident non-fatal IHD event in 19 studies (8 cohort studies, 11 case-control studies), incident fatal IHD event in two studies (both cohort studies), and incident non-fatal or fatal ("mixed") event in 16 studies (all cohort studies). Because we judged cohort studies to have a relatively lower risk of bias, we prioritized evidence from these studies and treated evidence from case-control studies as supporting evidence. For the bodies of evidence for both outcomes with any eligible studies (i.e. IHD incidence and mortality), we did not have serious concerns for risk of bias (at least for the cohort studies). No eligible study was found on the effect of long working hours on IHD prevalence. Compared with working 35-40 h/week, we are uncertain about the effect on acquiring (or incidence of) IHD of working 41-48 h/week (relative risk (RR) 0.98, 95% confidence interval (CI) 0.91 to 1.07, 20 studies, 312,209 participants, I² 0%, low quality of evidence) and 49-54 h/week (RR 1.05, 95% CI 0.94 to 1.17, 18 studies, 308,405 participants, I² 0%, low quality of evidence). Compared with working 35-40 h/week, working ≥55 h/week may have led to a moderately, clinically meaningful increase in the risk of acquiring IHD, when followed up between one year and 20 years (RR 1.13, 95% CI 1.02 to 1.26, 22 studies, 339,680 participants, I² 5%, moderate quality of evidence). Compared with working 35-40 h/week, we are very uncertain about the effect on dying (mortality) from IHD of working 41-48 h/week (RR 0.99, 95% CI 0.88 to 1.12, 13 studies, 288,278 participants, I² 8%, low quality of evidence) and 49-54 h/week (RR 1.01, 95% CI 0.82 to 1.25, 11 studies, 284,474 participants, I² 13%, low quality of evidence). Compared with working 35-40 h/week, working ≥55 h/week may have led to a moderate, clinically meaningful increase in the risk of dying from IHD when followed up between eight and 30 years (RR 1.17, 95% CI 1.05 to 1.31, 16 studies, 726,803 participants, I² 0%, moderate quality of evidence). Subgroup analyses found no evidence for differences by WHO region and sex, but RRs were higher among persons with lower SES. Sensitivity analyses found no differences by outcome definition (exclusively non-fatal or fatal versus "mixed"), outcome measurement (health records versus self-reports) and risk of bias ("high"/"probably high" ratings in any domain versus "low"/"probably low" in all domains).

CONCLUSIONS

We judged the existing bodies of evidence for human evidence as "inadequate evidence for harmfulness" for the exposure categories 41-48 and 49-54 h/week for IHD prevalence, incidence and mortality, and for the exposure category ≥55 h/week for IHD prevalence. Evidence on exposure to working ≥55 h/week was judged as "sufficient evidence of harmfulness" for IHD incidence and mortality. Producing estimates for the burden of IHD attributable to exposure to working ≥55 h/week appears evidence-based, and the pooled effect estimates presented in this systematic review could be used as input data for the WHO/ILO Joint Estimates.