The Relationship Between Strategic Human Resource Management Practices and the Employment of Vulnerable Workers: A Two-Wave Study Among Employers.

PURPOSE: To improve the inclusion of vulnerable workers in the labor market, employer behavior is key. However, little is known about the effectiveness of strategic Human Resource Management (HRM) practices that employers use to employ vulnerable workers. Therefore, this exploratory study investigates the association between strategic HRM practices (based on social legitimacy, economic rationality and employee well-being) and the actual and intended employment of vulnerable workers in the future. METHODS: In total, 438 organizations included in the Netherlands Employers Work Survey participated in a two-wave study with a nine-month follow-up period. Logistic regression models were used to estimate the relationship between strategic HRM practices (T0) with the employment of vulnerable workers (T1) and intentions to hire vulnerable workers (T1), while controlling for organizational size, sector, and employment of vulnerable workers at baseline. RESULTS: Employers who applied strategic HRM practices based on social legitimacy (e.g., inclusive mission statement or inclusive recruitment) or economic rationality (e.g., making use of reimbursements, trial placements, or subsidies) at T0 were more likely to employ vulnerable workers and to intend to hire additional vulnerable workers at T1. No significant results were found for practices related to employee well-being. CONCLUSION: Since different types of strategic HRM practices contribute to the inclusion of vulnerable workers, employers can build on their strategic priorities and strengths to create inclusive HRM approaches. Future research is needed to study whether these strategic HRM domains also relate to sustainable employment of vulnerable workers.

Associations of sustained smoking and smoking cessation with work-related outcomes: a longitudinal analysis.

PURPOSE: The aim of this study was to assess the association between sustained smoking and quitting with work-related outcomes among older workers. METHODS: We categorized a sample of older employees into non-smokers, sustained smokers and quitters. Multivariable regression models were used to test longitudinal associations of sustained smoking and smoking cessation with sickness absence, productivity loss and work ability. RESULTS: We included 3612 non-smokers, 673 sustained smokers and 246 quitters. Comparing sustained smokers to non-smokers, we found higher (but not statistically significant) sickness absence for sustained smokers [1.01, 95% confidence interval (CI) - 0.16-2.17]. We did not find differences in productivity loss (OR 0.82, 95% CI 0.60-1.13) and work ability (0.05, 95% CI -0.05-0.15). For employees with a relatively high physical health at baseline, comparing quitters to sustained smokers, we found higher (but not statistically significant) productivity loss for quitters (OR 2.23, 95% CI 0.94-5.31), and no difference in sickness absence (0.10, 95% CI - 2.67-2.87), and work ability (- 0.10, 95% CI -  0.36-0.16). For employees with a relatively low physical health at baseline, comparing quitters to sustained smokers, we found a statistically significant lower work ability (- 0.31, 95% CI - 0.57-0.05), and no difference in sickness absence (2.53, 95% CI - 1.29-6.34) and productivity loss (OR 1.26, 95% CI 0.66-2.39). CONCLUSIONS: We found no evidence that sustained smokers have less favorable work-related outcomes than non-smokers or that quitters have more favorable work-related outcomes than sustained smokers. The benefits of smoking cessation for employers might take a longer time to develop.

Long-term sickness absence in a working population: development and validation of a risk prediction model in a large Dutch prospective cohort.

BACKGROUND: Societal expenditures on work-disability benefits is high in most Western countries. As a precursor of long-term work restrictions, long-term sickness absence (LTSA) is under continuous attention of policy makers. Different healthcare professionals can play a role in identification of persons at risk of LTSA but are not well trained. A risk prediction model can support risk stratification to initiate preventative interventions. Unfortunately, current models lack generalizability or do not include a comprehensive set of potential predictors for LTSA. This study is set out to develop and validate a multivariable risk prediction model for LTSA in the coming year in a working population aged 45-64 years. METHODS: Data from 11,221 working persons included in the prospective Study on Transitions in Employment, Ability and Motivation (STREAM) conducted in the Netherlands were used to develop a multivariable risk prediction model for LTSA lasting ≥28 accumulated working days in the coming year. Missing data were imputed using multiple imputation. A full statistical model including 27 pre-selected predictors was reduced to a practical model using backward stepwise elimination in a logistic regression analysis across all imputed datasets. Predictive performance of the final model was evaluated using the Area Under the Curve (AUC), calibration plots and the Hosmer-Lemeshow (H&L) test. External validation was performed in a second cohort of 5604 newly recruited working persons. RESULTS: Eleven variables in the final model predicted LTSA: older age, female gender, lower level of education, poor self-rated physical health, low weekly physical activity, high self-rated physical job load, knowledge and skills not matching the job, high number of major life events in the previous year, poor self-rated work ability, high number of sickness absence days in the previous year and being self-employed. The model showed good discrimination (AUC 0.76 (interquartile range 0.75-0.76)) and good calibration in the external validation cohort (H&L test: p = 0.41). CONCLUSIONS: This multivariable risk prediction model distinguishes well between older workers with high- and low-risk for LTSA in the coming year. Being easy to administer, it can support healthcare professionals in determining which persons should be targeted for tailored preventative interventions.

Health differences between multiple and single job holders in precarious employment in the Netherlands: A cross-sectional study among Dutch workers.

INTRODUCTION: Precarious employment is associated with poor health. Among employees in precarious employment, those with multiple jobs may face additional health risks, e.g. due to combining work schedules and job roles. Our research question is: do differences in health exist between multiple and single job holders in precarious employment? METHODS: Participants in the Netherlands Working Conditions Survey 2012 aged 25-64 years who were not employed through the Act on Social Work Provision and who had a precarious job were included. To select employees in precarious employment (n = 3,609), latent class analysis was performed, based on variables based on indicators described by Van Aerden. Differences in general self-perceived health, burnout complaints, musculoskeletal health, and sickness absence between multiple and single job holders were studied cross-sectionally using logistic regression analyses. RESULTS: No significant differences were found between multiple and single job holders in precarious employment for self-perceived health (OR = 0.9; 95%CI = 0.7-1.3), burnout complaints (OR = 0.9; 95%CI = 0.7-1.2), and musculoskeletal health (OR = 1.1; 95%CI = 0.8-1.5). In crude analyses, multiple job holders experienced less sickness absence than single job holders (OR = 0.7; 95%CI = 0.5-0.9). In adjusted analyses, this difference was no longer statistically significant (OR = 0.8; 95%CI = 0.6-1.0). CONCLUSIONS: Despite potential health risks related to multiple job holding, we did not find health differences between multiple and single job holders in precarious employment in the Netherlands. More longitudinal research is necessary to provide recommendations for policy makers regarding multiple job holders in precarious employment.

Health and prolonging working lives: an advisory report of the Health Council of The Netherlands.

Objective This opinion paper summarizes the main findings and recommendations of an advisory report on health and prolonging working life, which was requested by the Dutch Minister of Social Affairs and Employment. Methods The advisory report was compiled by a multidisciplinary committee of ten scientists appointed by the Health Council of The Netherlands. The committee`s aims were to (i) describe the health of the ageing population, (ii) describe how prolonging working life influences health, (iii) describe determinants, besides health, for prolonging working lives, and (iv) review the literature on interventions aimed at retaining or improving employability of older workers. Results The report was presented to the Minister on 26 June 2018. As the likelihood of health problems increases with age, prolonging working life may be difficult. In general, life expectancy increases and gains in life years and health seem mainly attributable to people aged >75 years. Work is good for mental health. However, it may be beneficial for mental health to stop working around the retirement age. Besides health, financial factors, lifestyle, motivation to work, and working conditions play a role in prolonging working life. A systematic review of the evidence indicated that interventions such as worksite health promotion or career development workshops can support older workers in this matter. Conclusions The Health Council advised the Dutch Government to focus on worksite health promotion and career development interventions as well as the improvement of their implementation. This requires a tailored approach as there is a large diversity in health among older workers and particularly between low- and high-educated people. With this in mind, it was further recommended to explore whether flexible pension schemes might better suit this diversity.

Distinguishing groups and exploring health differences among multiple job holders aged 45 years and older.

PURPOSE: To identify distinct groups of older multiple job holders and to explore health differences between these groups. METHODS: We selected respondents from STREAM, a Dutch cohort study among persons aged 45 years and older, who reported having multiple jobs (N = 702). We applied latent class analysis to identify groups of multiple job holders. The association between these groups and health, measured with the SF-12, was studied cross-sectionally and longitudinally (1 year of follow-up), using linear regression analyses. RESULTS: Four groups of older multiple job holders were identified: (1) a vulnerable group (N = 145), who preferred having one job, and had jobs with high demands and low resources; (2) an indifferent group (N = 134), who did not experience many benefits or disadvantages of multiple job holding (MJH); (3) a satisfied hybrid group, who were all self-employed in their second job (N = 310); and (4) a satisfied combination group, who all had a second job as an employee (N = 113). Both the satisfied hybrid and satisfied combination groups preferred MJH and experienced benefits of it. At baseline, the vulnerable group experienced significantly lower physical and mental health than the other groups. We found no significant differences regarding changes in health after 1 year. CONCLUSIONS: Four groups of older multiple job holders could be distinguished. The vulnerable group experienced lower physical and mental health at baseline than the other three groups. Policies and interventions supporting vulnerable multiple job holders may need to be developed. Future research is recommended to take heterogeneity among multiple job holders into account.

Employment status transitions in employees with and without chronic disease in the Netherlands.

OBJECTIVES: Objectives were to: (1) longitudinally assess transitions in employment status of employees with and without chronic disease; and (2) assess predictors of exit from paid employment. METHODS: Transitions in employment status at 1- and 2-year follow-up were assessed in a longitudinal cohort study of employees aged 15-63 years. Generalised estimating equations (GEE) and logistic regression analyses were performed to analyse differences in transitions and identify sociodemographic, health- and work-related predictors. RESULTS: At 1- and 2-year follow-up, 10,038 employees (37% with chronic disease) and 7636 employees responded. Employees with chronic disease had higher probability of leaving paid employment [OR 1.4 (1.1-1.6)] and unemployment, disability pension and early retirement. Employees without chronic disease had higher chance of moving into self-employment or study. At 2-year follow-up, employees with cardiovascular disease (15%), chronic mental disease (11%), diabetes (10%) and musculoskeletal disease (10%), had left paid employment most often. Higher age, poor health, burnout, low co-worker support and chronic disease limitations were predictors for leaving paid employment. CONCLUSIONS: Employees with chronic disease leave paid work more often for unfavourable work outcomes.

Predictors of working beyond retirement in older workers with and without a chronic disease - results from data linkage of Dutch questionnaire and registry data.

BACKGROUND: An increasing number of retirees continue to work beyond retirement despite being eligible to retire. As the prevalence of chronic disease increases with age, working beyond retirement may go along with having a chronic disease. Working beyond retirement may be different for retirees with and without chronic disease. We aim to investigate whether demographic, socioeconomic and work characteristics, health and social factors predict working beyond retirement, in workers with and without a chronic disease. METHODS: Employees aged 56-64 years were selected from the Study on Transitions in Employment, Ability and Motivation (N = 1125). Questionnaire data on demographic and work characteristics, health, social factors, and working beyond retirement were linked to registry data from Statistics Netherlands on socioeconomic characteristics. Separate prediction models were built for retirees with and without chronic disease using multivariate logistic regression analyses. RESULTS: Workers without chronic disease were more likely to work beyond retirement compared to workers with chronic disease (27% vs 23%). In retirees with chronic disease, work and health factors predicted working beyond retirement, while in retirees without a chronic disease, work, health and social factors predicted working beyond retirement. In the final model for workers with chronic disease, healthcare work, better physical health, higher body height, lower physical load and no permanent contract were positively predictive of working beyond retirement. In the final model for workers without chronic disease, feeling full of life and being intensively physically active for > = 2 days per week were positively predictive of working beyond retirement; while manual labor, better recovery, and a partner who did not support working until the statutory retirement age, were negatively predictive of working beyond retirement. CONCLUSIONS: Work and health factors independently predicted working beyond retirement in workers with and without chronic disease, whereas social factors only did so among workers without chronic disease. Demographic and socioeconomic characteristics did not independently contribute to prediction of working beyond retirement in any group. As prediction of working beyond retirement was more difficult among workers with a chronic disease, future research is needed in this group.

Predictors of transitions from single to multiple job holding: Results of a longitudinal study among employees aged 45-64 in the Netherlands.

OBJECTIVES: To construct prediction models for transitions to combination multiple job holding (MJH) (multiple jobs as an employee) and hybrid MJH (being an employee and self-employed), among employees aged 45-64. METHODS: A total of 5187 employees in the Netherlands completed online questionnaires annually between 2010 and 2013. We applied logistic regression analyses with a backward elimination strategy to construct prediction models. RESULTS: Transitions to combination MJH and hybrid MJH were best predicted by a combination of factors including: demographics, health and mastery, work characteristics, work history, skills and knowledge, social factors, and financial factors. Not having a permanent contract and a poor household financial situation predicted both transitions. Some predictors only predicted combination MJH, e.g., working part-time, or hybrid MJH, e.g., work-home interference. CONCLUSIONS: A wide variety of factors predict combination MJH and/or hybrid MJH. The prediction model approach allowed for the identification of predictors that have not been previously studied.

The longitudinal association between multiple job holding and long-term sickness absence among Danish employees: an explorative study using register-based data.

PURPOSE: Multiple job holding (MJH) is common in many countries, but little is known about its (health) consequences. Our aim is to explore the longitudinal association between MJH and long-term sickness absence (LTSA) among Danish employees. METHODS: We included employees (N = 8968) who participated in the Danish Work Environment Cohort Study (DWECS), based on a representative sample of the Danish working population. Three dichotomous independent variables were created: MJH in general, combination MJH (i.e. second job as employee) and hybrid MJH (i.e. self-employed in second job). LTSA (≥5 weeks) was measured using the Danish Register for Evaluation of Marginalization during 78 weeks of follow-up. Potential confounders included demographics, health, and work characteristics. Logistic regression analyses were performed to study whether LTSA was associated with MJH in general, combination MJH, and hybrid MJH. Interaction effects for gender, age, total working hours per week (≤37 or >37 h a week), and shift work were tested. RESULTS: In total, 11.7% (N = 1048) of the respondents reported having multiple jobs and 7.6% (N = 678) experienced LTSA during follow-up. After adjustment for confounders, no significant association between LTSA and MJH in general (OR = 0.82), combination MJH (OR = 0.81), or hybrid MJH (OR = 0.83) was found. Among employees working more than 37 h per week, combination MJH was associated with a higher likelihood of LTSA (OR = 1.50). CONCLUSIONS: We did not find evidence for an increased likelihood of LTSA among multiple job holders. Future research should study the likelihood of LTSA among subgroups of multiple job holders, e.g. those working long hours.

Predicting working beyond retirement in the Netherlands: an interdisciplinary approach involving occupational epidemiology and economics.

Objectives No study so far has combined register-based socioeconomic information with self-reported information on health, demographics, work characteristics, and the social environment. The aim of this study was to investigate whether socioeconomic, health, demographic, work characteristics and social environmental characteristics independently predict working beyond retirement. Methods Questionnaire data from the Study on Transitions in Employment, Ability and Motivation were linked to data from Statistics Netherlands. A prediction model was built consisting of the following blocks: socioeconomic, health, demographic, work characteristics and the social environment. First, univariate analyses were performed (P0<.15), followed by correlations and logistic multivariate regression analyses with backward selection per block (P0<.15). All remaining factors were combined into one final model (P0<.05). Results In the final model, only factors from the blocks health, work and social environmental characteristics remained. Better physical health, being intensively physically active for >2 days/week, higher body height, and working in healthcare predicted working beyond retirement. If respondents had a permanent contract or worked in handcraft, or had a partner that did not like them to work until the official retirement age, they were less likely to work beyond retirement. Conclusion Health, work characteristics and social environment predicted working beyond retirement, but register-based socioeconomic and demographic characteristics did not independently predict working beyond retirement. This study shows that working beyond retirement is multifactorial.

"Mental retirement?" Trajectories of work engagement preceding retirement among older workers.

Objectives Before actual retirement, employees may already distance themselves from work, which could be referred to as "mental retirement". However, trajectories of work motivation, ie, work engagement, have not been studied yet. The present study aimed to (i) identify different trajectories of work engagement among older workers approaching the retirement age, and (ii) examine their associations with actual retirement. Methods In total 3171 employees aged 55-62 years, who participated in the Dutch Study on Transitions in Employment, Ability and Motivation were included in this study. Participants completed questionnaires in 2010, 2011, 2012, and 2013. Latent class growth mixture modeling was performed to identify groups of employees with similar three-year trajectories in work engagement. Logistic regression analyses were performed to study whether trajectory membership was associated with retirement. Results Of the 3171 employees, 16.2% made a transition from work to (early) retirement (N=513). Four trajectories of work engagement were identified: steady high (76.3%), steady low (12.7%), decreasing (6.2%), and increasing (4.8%). A steady low work engagement trajectory was associated with retirement [odds ratio (OR) 1.46], compared to a steady high work engagement trajectory. Although not statistically significant, an increasing work engagement trajectory seemed to be associated with retirement as well (OR 1.60). Conclusions This study did not support the concept of mental retirement before actual retirement, ie, a decrease in work engagement among those facing retirement. However, as one in eight employees did experience steady low work engagement in the years before retirement, interventions promoting work motivation are recommended to support the employability of these employees.

Long working hours and cancer risk: a multi-cohort study.

BACKGROUND: Working longer than the maximum recommended hours is associated with an increased risk of cardiovascular disease, but the relationship of excess working hours with incident cancer is unclear. METHODS: This multi-cohort study examined the association between working hours and cancer risk in 116 462 men and women who were free of cancer at baseline. Incident cancers were ascertained from national cancer, hospitalisation and death registers; weekly working hours were self-reported. RESULTS: During median follow-up of 10.8 years, 4371 participants developed cancer (n colorectal cancer: 393; n lung cancer: 247; n breast cancer: 833; and n prostate cancer: 534). We found no clear evidence for an association between working hours and the overall cancer risk. Working hours were also unrelated the risk of incident colorectal, lung or prostate cancers. Working ⩾55 h per week was associated with 1.60-fold (95% confidence interval 1.12-2.29) increase in female breast cancer risk independently of age, socioeconomic position, shift- and night-time work and lifestyle factors, but this observation may have been influenced by residual confounding from parity. CONCLUSIONS: Our findings suggest that working long hours is unrelated to the overall cancer risk or the risk of lung, colorectal or prostate cancers. The observed association with breast cancer would warrant further research.

Company Policies on Working Hours and Night Work in Relation to Older Workers' Work Ability and Work Engagement: Results From a Dutch Longitudinal Study with 2 Year Follow-Up.

Purpose To longitudinally investigate (1) whether lower work ability and work engagement predict the use of company policies on reduced working hours and exemption from evening/night work among older workers, and (2) whether using such policies subsequently contribute to higher work ability and work engagement. Methods In total 6922 employees (45-64 years) participating in the first three waves of the Study on Transitions in Employment, Ability and Motivation were included. Participants yearly filled out an online questionnaires. Regression analyses were applied to study the influence of baseline work ability and work engagement on the incident use of policies during the first year of follow-up, and the incident use of these policies on work ability and work engagement during the second year of follow-up. Results Employees with a higher work ability were less likely to start using the policy 'reduced working hours' [OR 0.91 (95 % CI 0.83-0.98)]. Starting to use this policy was in turn related to lower work ability 1 year later [B -0.28 (95 % CI -0.47 to -0.08)]. Starting to use the policy 'exemption from evening/night work' was related to higher work engagement 1 year later [B 0.23 (95 % CI 0.07-0.39)]. Conclusions Low work ability precedes the use of some company policies aiming to support sustainable employability of older workers. Further research is needed to explore whether company policies result in a (longstanding) improvement, or reduced deterioration, of older workers' employability.

Long working hours and risk of coronary heart disease and stroke: a systematic review and meta-analysis of published and unpublished data for 603,838 individuals.

BACKGROUND: Long working hours might increase the risk of cardiovascular disease, but prospective evidence is scarce, imprecise, and mostly limited to coronary heart disease. We aimed to assess long working hours as a risk factor for incident coronary heart disease and stroke. METHODS: We identified published studies through a systematic review of PubMed and Embase from inception to Aug 20, 2014. We obtained unpublished data for 20 cohort studies from the Individual-Participant-Data Meta-analysis in Working Populations (IPD-Work) Consortium and open-access data archives. We used cumulative random-effects meta-analysis to combine effect estimates from published and unpublished data. FINDINGS: We included 25 studies from 24 cohorts in Europe, the USA, and Australia. The meta-analysis of coronary heart disease comprised data for 603,838 men and women who were free from coronary heart disease at baseline; the meta-analysis of stroke comprised data for 528,908 men and women who were free from stroke at baseline. Follow-up for coronary heart disease was 5·1 million person-years (mean 8·5 years), in which 4768 events were recorded, and for stroke was 3·8 million person-years (mean 7·2 years), in which 1722 events were recorded. In cumulative meta-analysis adjusted for age, sex, and socioeconomic status, compared with standard hours (35-40 h per week), working long hours (≥55 h per week) was associated with an increase in risk of incident coronary heart disease (relative risk [RR] 1·13, 95% CI 1·02-1·26; p=0·02) and incident stroke (1·33, 1·11-1·61; p=0·002). The excess risk of stroke remained unchanged in analyses that addressed reverse causation, multivariable adjustments for other risk factors, and different methods of stroke ascertainment (range of RR estimates 1·30-1·42). We recorded a dose-response association for stroke, with RR estimates of 1·10 (95% CI 0·94-1·28; p=0·24) for 41-48 working hours, 1·27 (1·03-1·56; p=0·03) for 49-54 working hours, and 1·33 (1·11-1·61; p=0·002) for 55 working hours or more per week compared with standard working hours (ptrend<0·0001). INTERPRETATION: Employees who work long hours have a higher risk of stroke than those working standard hours; the association with coronary heart disease is weaker. These findings suggest that more attention should be paid to the management of vascular risk factors in individuals who work long hours. FUNDING: Medical Research Council, Economic and Social Research Council, European Union New and Emerging Risks in Occupational Safety and Health research programme, Finnish Work Environment Fund, Swedish Research Council for Working Life and Social Research, German Social Accident Insurance, Danish National Research Centre for the Working Environment, Academy of Finland, Ministry of Social Affairs and Employment (Netherlands), US National Institutes of Health, British Heart Foundation.

Job strain and the risk of stroke: an individual-participant data meta-analysis.

BACKGROUND AND PURPOSE: Psychosocial stress at work has been proposed to be a risk factor for cardiovascular disease. However, its role as a risk factor for stroke is uncertain. METHODS: We conducted an individual-participant-data meta-analysis of 196 380 males and females from 14 European cohort studies to investigate the association between job strain, a measure of work-related stress, and incident stroke. RESULTS: In 1.8 million person-years at risk (mean follow-up 9.2 years), 2023 first-time stroke events were recorded. The age- and sex-adjusted hazard ratio for job strain relative to no job strain was 1.24 (95% confidence interval, 1.05;1.47) for ischemic stroke, 1.01 (95% confidence interval, 0.75;1.36) for hemorrhagic stroke, and 1.09 (95% confidence interval, 0.94;1.26) for overall stroke. The association with ischemic stroke was robust to further adjustment for socioeconomic status. CONCLUSION: Job strain may be associated with an increased risk of ischemic stroke, but further research is needed to determine whether interventions targeting job strain would reduce stroke risk beyond existing preventive strategies.

The role of ability, motivation, and opportunity to work in the transition from work to early retirement--testing and optimizing the Early Retirement Model.

OBJECTIVES: Determinants in the domains health, job characteristics, skills, and social and financial factors may influence early retirement through three central explanatory variables, namely, the ability, motivation, and opportunity to work. Based on the literature, we created the Early Retirement Model. This study aims to investigate whether data support the model and how it could be improved. METHODS: Employees aged 58-62 years (N=1862), who participated in the first three waves of the Dutch Study on Transitions in Employment, Ability and Motivation (STREAM) were included. Determinants were assessed at baseline, central explanatory variables after one year, and early retirement after two years. Structural equation modeling was applied. RESULTS: Testing the Early Retirement Model resulted in a model with good fit. Health, job characteristics, skills, and social and financial factors were related to the ability, motivation and/or opportunity to work (significant ß range: 0.05-0.31). Lower work ability (ß=-0.13) and less opportunity to work (attitude colleagues and supervisor about working until age 65: ß=-0.24) predicted early retirement, whereas the motivation to work (work engagement) did not. The model could be improved by adding direct effects of three determinants on early retirement, ie, support of colleagues and supervisor (ß=0.14), positive attitude of the partner with respect to early retirement (ß=0.15), and not having a partner (ß=-0.13). CONCLUSIONS: The Early Retirement Model was largely supported by the data but could be improved. The prolongation of working life might be promoted by work-related interventions focusing on health, work ability, the social work climate, social norms on prolonged careers, and the learning environment.

Night work and breast cancer risk in a general population prospective cohort study in The Netherlands.

Experimental studies in animals indicate that disruption of the circadian rhythm is carcinogenic, and night work has been suggested to be a probable breast cancer cause in humans. Findings among humans, however are inconsistent, often gathered with retrospective study designs, and only based on specific populations, such as nurses. We used data on night work collected in the Dutch Labor Force Surveys of 1996 until 2009, and individually linked these with National registers on hospital admission. Among 285,723 women without breast cancer at baseline, 2,531 had a hospital admission for breast cancer during an average of 7 years of follow up in the registers. Occasional and regular night work were not associated with the risk of hospital admission for breast cancer (adjusted hazard ratios 1.04; 95 % confidence interval 0.85-1.27, and 0.87; 0.72-1.05, respectively). Working more hours per week, or more years in a job entailing night work did not show increased breast cancer risks. Hazard ratios neither differed between nurses and women with other occupations. Our results show no association of night work with incident breast cancer, and suggest that night work generally does not increase the risk of breast cancer among women in the Dutch working population.