Long working hours and depressive symptoms: moderating effects of gender, socioeconomic status, and job resources

Gender differences in the association between long work hours, weekend work, and insomnia symptoms in a nationally representative sample of workers in Korea

OBJECTIVES

Long work hours and weekend work can negatively impact worker sleep; however, gender differences in these relationships have not been sufficiently studied. We explored the association between long work hours, weekend work, and insomnia symptoms, as well as the moderating effect of gender on this association.

METHODS

A nationwide sample of 42,476 Korean workers (52.8% women) was analyzed. The main exposure variables were weekly work hours and monthly weekend days worked. Insomnia symptoms were measured using the Minimal Insomnia Symptom Scale. Logistic regression was used to estimate odds ratios (ORs) and confidence intervals (CIs).

RESULTS

Among the study sample, 10.5% worked ≥55hours weekly and 9.6% worked ≥5 weekend days monthly. The OR (95% CI) of an association between long work hours and insomnia symptoms was 1.72 (1.48-2.00) for 49-54hours, and 2.01 (1.71-2.37) for ≥55hours among men and 1.26 (1.03-1.55) for 49-54hours, and 1.03 (0.83-1.27) for ≥55hours among women. The OR (95% CI) of an association between monthly weekend days worked and insomnia symptoms was 1.68 (1.50-1.90) for 1-4days and 1.92 (1.62-2.29) for ≥5days among men and 1.20 (1.05-1.36) for 1-4days and 1.54 (1.28-1.86) for ≥5days among women.

CONCLUSION

Long work hours and weekend work are associated with insomnia symptoms, and this association is more pronounced among men than women. Policy interventions are warranted to reduce the burden of long work hours and weekend work.

Socioeconomic inequalities in the relationship between internet usage patterns and depressive symptoms: Evidence from a Chinese longitudinal study

Background

The increasing prevalence of depressive symptoms has emerged as a critical public health issue globally, highlighting the need for analyses of the factors contributing to depressive symptoms within the Chinese population and the development of targeted recommendations for improving mental well-being. We aimed to explore the correlation between internet use and depressive symptoms and the role of socioeconomic inequalities in this association.

Methods

We included data on 8019 residents aged 18 years and above, which we retrieved from the 2018 and 2020 waves of the China Family Panel Studies. We used latent profile analysis to categorise individuals' internet usage patterns and multiple linear regression to determine their association with depressive symptoms.

Results

Higher socioeconomic status (SES) was associated with fewer depressive symptoms (τ = -0.08; 95% confidence interval (CI) = -0.36, -0.18). Individuals in the high-dependence group presented a greater likelihood of developing depressive symptoms (τ = 0.04; 95% CI = 0.007, 0.66). We observed no significant difference in the interaction effect between individual-level SES and the four patterns of internet usage. However, compared with urban-dwelling respondents, those in rural areas had a stronger association between internet usage patterns and depressive symptoms, especially those in the high-dependence group (τ = -0.07; 95% CI = -1.47, -0.20).

Conclusions

Our findings indicate a significant association between depressive symptoms and internet usage patterns, indicating a need for interventions related to internet use, especially those targeted at reducing the risk of depressive symptoms in individuals of lower SES.

Impact of Long Working Hours on Mental Health Status in Japan: Evidence from a National Representative Survey

Using the 2010-2019 Comprehensive Survey of Living Conditions (CSLC) conducted in Japan, we examined the impact of long working hours on mental health in Japan while addressing the endogeneity issue arising from non-random selection bias. We assessed the variations in the effects of long working hours on mental health across different groups. The results show that first, individuals working longer hours (55 h or more per week) exhibited a higher likelihood of developing mental illness than those working regular hours or fewer hours. Second, the negative effect of long working hours on mental health is more pronounced among non-regular workers than among regular workers. Third, the effect of long working hours on mental health varies among different demographic groups, with a greater impact observed among women, managers, non-regular workers, employees in small- or large-sized firms, and those in smaller cities compared to their counterparts. Thus, to enhance worker productivity, the Japanese government should address the issue of long working hours to improve employees' mental well-being. Initiatives aimed at promoting work-life balance, family-friendly policies, and measures to ameliorate working conditions are expected to help mitigate the challenges associated with long working hours and mental health issues, especially among non-regular workers.

Association between long working hours and the onset of problematic alcohol use in young workers: A population-based longitudinal analysis in South Korea

BACKGROUND

Long working hours can negatively impact mental health. We examined the association between long working hours and problematic alcohol use among young Korean workers.

METHODS

We included a nationally representative sample of workers below the age of 40 from the Youth Panel between 2016 and 2020 (N = 7846; observations: 27,646). The exposure variable was working hours per week. Problematic alcohol use was assessed using the CAGE questionnaire, and generalized estimating equations were used to account for repeated measurements.

RESULTS

Observations of the participants revealed that 5 % worked < 35 h/week, 51 % worked 35-40 h/week, 24 % worked 41-48 h/week, 11 % worked 49-54 h/week, and 9 % worked ≥55 h/week. The prevalence of problematic alcohol use among the workers was 2 % for <35 h/week, 2 % for 35-40 h/week, 3 % for 41-48 h/week, 4 % for 49-54 h/week, and 4 % for ≥55 h/week. The adjusted odds ratios (95 % confidence intervals) for the association between working hours per week and the onset of problematic alcohol use in the following year were 0.86 (0.45-1.66) for <35 h, 1.56 (1.22-1.99) for 41-48 h, 2.03 (1.49-2.75) for 49-54 h, and 1.68 (1.17-2.42) for ≥55 h, compared to 35-40 h.

LIMITATIONS

The observational design of the study prevented the establishment of a causal relationship between working hours and the onset of problematic alcohol use.

CONCLUSION

Long working hours were associated with the development of problematic alcohol use. Policy interventions should promote healthier drinking habits among workers with long work hours.

Prevalence and risk factors of physical and psychological health among readymade garment workers in Bangladesh

Objective. Poor health outcomes of Bangladeshi readymade garment (RMG) workers tend to be associated with a variety of occupational factors. This study aimed to investigate the prevalence of, and risk factors associated with, the physical and psychological health outcomes of Bangladeshi RMG workers. Methods. Responses to a cross-sectional survey from a convenience sample of 411 adult Bangladeshi RMG workers (mean age = 26.24 years; SD 6.40 years; female = 80%) were analysed using bivariate and multivariate (logistic regression models) analyses. Results. More than half of the participants reported headaches (61.6%) and colds/flu (51.3%), followed by fever (37.2%), diarrhoea (32.8%), bodily pain (29.9%) and respiratory infections (20.9%). For psychological health, stress (69.1%), anxiety (66.2%) and boredom (64.5%) were most prevalent, followed by sleeplessness (51.3%), depression (48.2%) and fear (34.3%). RMG workers from the factories located in Chattogram (a peripheral region compared to Dhaka) reported poorer physical and psychological health outcomes than those working in factories in Dhaka (the capital city of Bangladesh). Overall, compared to males, female RMG workers were more likely to be vulnerable to both physical and psychological health outcomes. Conclusion. Improvement in workplace conditions and safety programmes is needed to safeguard the overall health outcomes of Bangladeshi RMG workers.

Association between overtime and depressive symptoms among Chinese employees

Objectives

This study examines the correlation between overtime and depressive symptoms, and analyzed the moderating effect of age, education level, and income level on their correlation by using a nationally representative sample from the Chinese Family Panel Studies (CFPS) in 2018.

Methods

Participants are divided into three groups: 30-44 h/week, 44.1-61.9 h/week (defined as overtime group), and ≥ 62 h/week (heavy overtime group). The multiple ordered logistic regression models are conducted to estimate the association between overtime and depressive symptoms. The interaction term of overtime and moderators including age, education level, and income level are introduced into the models to test the moderating effect.

Results

The overtime group have an increased probability of depressive symptoms (OR = 1.11, 95% CI 1.04-1.20) compared with those who reported working hours 30-44 h/week, after controlling for important confounders. What's more, the worsening of depressive symptoms is more pronounced in the heavy overtime group (OR = 1.32, 95% CI 1.22-1.44). The moderating effect results show that younger employees, employees with high education levels, and those with high income level are more likely to be affected by the negative effects of overtime.

Conclusion

Working overtime increased the likelihood of depressive symptoms. Younger employees, high-educated employees and employees with high income level are more vulnerable to the negative effects of overtime on mental health.

The moderating role of physical activity on the relationship between work intensity and depressive symptoms among the employees

Our aim was to examine the associations between work intensity and depressive symptoms among the working population, as well as to identify the impact of physical activity (PA) on these relationships. Spearman correlation analysis was conducted to analyze the correlations among work intensity, PA, and depressive symptoms. Working hours and working days were positively correlated with depressive symptoms (r = 0.108, 0.063; all p values were <0.001). Regular PA, exercise time, exercise frequency, and exercise years were negatively correlated with depressive symptoms (r = -0.121, -0.124, -0.152, -0.149; all p values were <0.001) and working days (r = -0.066, -0.050, -0.069, -0.044; all p values were <0.001), working hours (r = -0.113. -0.106, -0.161, -0.123; all p values were <0.001). Working days was positively correlated with working hours (r = 0.512, p < 0.001). Different levels of PA alleviated the effect of working hours or working days on depressive symptoms. Working hours seemed to be more correlated with depressive symptoms than working days. The results suggest that PA at any level could buffer against the effects of work intensity and might prove a helpful strategy for improving mental health issues among employees.

Protection of gender health and fight against gender violence during the COVID-19 pandemic: the experience of our street clinic in a disadvantaged suburb of Rome Metropolitan City

OBJECT

In this study, we evaluated health, social inequalities and risk to gender violence of women living in a disadvantaged degraded suburb of Rome Metropolitan City, during COVID-19 pandemic.

METHODS

The study included 779 women referring to primary care services of Medicina Solidale Institute for gynecological/breast examinations (209), medical and support aid for the children (383) and COVID-19 test execution (187).

RESULTS

The data show that most women (68%) were unemployed or had an irregular job. The request of support varied depending on the ethnicity: while healthcare support was requested mostly by African female community, the COVID-19 test, mandatory for public transportation and work, was a need of the east-european community. Both these communities referred to Medical Solidale primary care service for the healthcare and food/clothing support for their children. It is interesting to note that the requests from the Italian women community was elevated in terms of personal healthcare, support for the children and COVID-19 test execution. The access to the national health system (NHS) resulted a complex administrative procedure despite the original social-ethnic communities. The vast majority of women lacked awareness of their crucial role for supporting the family entity, while inadequacy was commonly reported.

CONCLUSIONS

This study confirms a critical condition for women living in disadvantaged neighborhoods, whose vulnerability is further worsened by the limited access to primary care assistance with serious consequences for health and quality of life. Prevention and treatment, especially for the most vulnerable subjects, should be a priority for the public health system.

Association between long working hours and mental health among nurses in China under COVID-19 pandemic: based on a large cross-sectional study

OBJECTIVE

Nurses were more likely to experience mental disorders due to long working hours and irregular schedules. However, studies addressing this issue are scarce; therefore, we aimed to investigate the association between long working hours and mental health in Chinese nurses during the coronavirus disease pandemic.

METHODS

A cross-sectional study was conducted with 2,811 nurses at a tertiary hospital in China from March to April 2022. We collected data on demographic, psychological characteristics, dietary habits, life, and work-related factors using a self-reported questionnaire and measured mental health using Patient Health Questionnaire-9 and General Anxiety Disorder-7. Binary logistic regression to determine adjusted odds ratios and 95% confidence intervals.

RESULTS

The effective response rates were 81.48%, 7.80% (219), and 6.70% (189) of the respondents who reported depression and anxiety, respectively. We categorized the weekly working hours by quartiles. Compared with the lowest quartile, the odds ratios and 95% confidence intervals across the quartiles for depression after adjustment were 0.98 (0.69, 1.40), 10.58 (2.78, 40.32), and 1.79 (0.81, 3.97) respectively, the P for trend was 0.002. The odds ratios across the quartiles for anxiety after adjustment were 0.87 (0.59, 1.30), 8.69 (2.13, 35.46), and 2.67 (1.26, 5.62), respectively, and the P for trend was 0.008.

CONCLUSIONS

This study demonstrated that extended working hours increased the risk of mental disorders among nurses during the coronavirus disease pandemic, particularly in those who worked more than 60 h per week. These findings enrich the literature on mental disorders and demonstrate a critical need for additional studies investigating intervention strategies.

Executive summary of the Merck Animal Health Veterinarian Wellbeing Study III and Veterinary Support Staff Study

OBJECTIVE

Merck Animal Health Veterinarian Wellbeing Study III was conducted to continue to monitor mental health and well being within the veterinary profession in the US and to identify factors associated with high levels of wellbeing and lack of serious psychological distress.

METHODS

A questionnaire consisting of several instruments and questions for measurement of mental health and wellbeing was completed by 2,495 veterinarians and 448 veterinary support staff. Results for veterinarians were weighted to the US AVMA membership.

RESULTS

This study revealed that wellbeing and mental health of some veterinarians declined over the past 2 years, driven in part by the COVID-19 pandemic and extreme labor shortages. Burnout remained at a high level, but there was no increase in suicide ideation. A new companion survey of veterinary support staff demonstrated that staff scored lower in wellbeing and mental health, and higher in burnout than veterinarians.

CLINICAL RELEVANCE

Importantly, these studies identified techniques that both individuals and employers may find useful in fostering wellbeing and good mental health. A healthy method for coping with stress and good work-life balance was important, as was engaging a financial adviser for those with student debt or other financial stresses. Employers should create safe environments where employees feel comfortable seeking help, reducing the stigma associated with mental health issues. In addition, employers can provide Employee Assistance Programs and health insurance that covers mental health treatment. Fostering a healthy work culture was also important, one with good communication, teamwork, trust, and adequate time allotted to provide quality patient care.

Factors associated with symptoms of poor mental health among women factory workers in China's supply chain

OBJECTIVE

Foreign direct investment (FDI) to China has motivated increased labor migration to export processing zones (EPZs). Work environments with high occupational stress, such as production line jobs typical in EPZs, have been associated with adverse mental health symptoms.

METHODS

A cross-sectional survey that examined occupational stress and symptoms of poor mental health was implemented among Chinese women factory workers in three electronic factories in the Tianjin Economic-Technological Development Area. Symptoms of mental health measured in the survey were hopelessness, depression, not feeling useful or needed, and trouble concentrating. Crude and adjusted prevalence odds ratios and their 95% confidence intervals were calculated with logistic regression.

RESULTS

Responses were collected from 696 women factory workers. Participants were aged 18-56 years (mean 28 ± 5.8), 66% of whom were married and 25% of whom were migrants. Nearly 50% of participants reported at least one symptom of poor mental health. After adjusting for covariates associated with each outcome in the bivariate analysis, high job strain was associated with hopelessness (OR 2.68, 95% CI 1.58, 4.56), not feeling useful (OR 2.05, 95% CI 1.22, 3.43), and feeling depressed (OR 1.78, 95% CI 1.16, 2.72).

CONCLUSION

This study expands on the international body of research on the well-being of women working in the global supply chain and provides evidence on the associations between occupational stressors, migration, and social support on symptoms of poor mental health among women workers. Future research to better understand and improve psychological health and to prevent suicide among workers in China's factories is critical to improve the health of China's labor force.

Overtime working patterns and adverse events in work-related suicide cases: hierarchical cluster analysis of national compensation data in Japan (fiscal year 2015-2016)

Background

Although various work-related adverse events affect workers’ mental health, the association between long working hours and mental disorders remains unclear. We investigated the characteristics of overtime work and work-related adverse events among all cases of compensated work-related suicide in Japan to empirically reveal the context of the serious consequences.

Methods

We analysed all 167 cases of mental disorders resulting in suicide that were compensated in fiscal year 2015–2016. Hierarchical clustering was applied to the overtime working history. Work-related adverse events were also evaluated as the qualitative aspects of their jobs.

Results

More than half of the cases committed suicide within a month of developing a mental disorder. The Administrative and professional or engineering workers had a higher suicide rate. The clustering analysis revealed chronic long working hours (19%), gradual increase (27%), or rapid increase (25%) in working hours before the onset of a mental disorder. A group of cases with less overwork experienced more interpersonal conflicts.

Conclusion

This is the first study to employ a clustering technique to objectively reveal the actual working patterns behind suicide. The patterns of working overtime before the onset of mental disorders varied considerably among the cases. Taking the transition of working overtime into account may provide clearer insight into the relationship between long working hours and workers’ mental health. These results highlight the need for countermeasures especially for causes of chronic overworking, drastic increases in working hours, and interpersonal conflicts to prevent work-related suicide.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00420-021-01760-5.

Relationship Between Work Engagement and the Onset of Long-term Sickness Absence Due to Mental Disorders: A 4-year Retrospective Cohort Study

The aim of the present study was to investigate the association between work engagement and long-term sickness absence due to mental disorders such as mood disorders and anxiety, and whether the relationship differs between men and women, during a 4-year follow-up period. Data were obtained from 21,293 workers at four pharmaceutical companies belonging to the Collabo-Health Study Group in 2014. The baseline data were collected by self-administered questionnaires. We obtained information about long-term sickness absence from the personnel records of the surveyed companies from the baseline survey in 2014 until March 2018. Hazard ratios (HRs) and 95% confidence intervals (CIs) using the low work engagement group as a reference were calculated by Cox proportional hazards analysis as the outcome, defined as the period leading to mental health-related sick leave. A total of 12,025 participants had complete data for analysis, and 123 exhibited long-term sickness absence during a 4-year follow-up period. The high work engagement group for men had a significantly lower HR (0.52, 95% CI: 0.31-0.88, P = 0.015) compared with the low work engagement group. Conversely, among women, the moderate work engagement group had a significantly higher HR (2.44, 95% CI: 1.03-5.84, P = 0.043) compared with the low work engagement group. Work engagement in men may predict the occurrence of long-term sickness absence due to mental disorders in the subsequent four years, but this relationship was different in women. Further research is needed to clarify this issue.

Effect of internet-based attention bias modification on the anxiety of Japanese workers: A randomized controlled trial

Objectives

This study comprised a randomized controlled trial to examine the effect of internet‐based attention bias modification (iABM) on reducing workers' anxiety.

Methods

In total, 300 eligible participants were randomized according to sex and age; 180 were assigned to the intervention group and 120 to the control group. The word stimuli used in the iABM included eight positive words and eight neutral words. Participants were instructed to indicate the positive word's position as quickly and accurately as possible by tapping one of the two directions on display. The intervention included five sessions per participant over 1 month, resulting in a total of 600 trials. The main outcome measure was the total state anxiety score of the State‐Trait Anxiety Inventory (STAI).

Results

There was no significant difference in the net change in STAI scores between the intervention and control groups. The mean reaction time of the fifth session was significantly shorter than the mean reaction time of the first session. Furthermore, although there was no effect on the index of effect size Δ, the paired t‐test showed a significant decrease in the anxiety score.

Conclusions

The iABM intervention in this study did not enhance the amelioration of workers' anxiety when compared with the control condition.

Effect of long working hours and insomnia on depressive symptoms among employees of Chinese internet companies

BACKGROUND

In China, long working hours and insomnia are relatively common among internet company employees. Considering that both can affect mental health, we examined their independent and interaction effects on these employees' depressive symptoms (DS).

METHODS

We analyzed data from the 2016 occupational health questionnaire survey conducted in 35 large-, medium-, and small-scale internet companies. Overall, 3589 full-time employees were recruited to evaluate the association among working hours, insomnia, and DS. The Patient Health Questionnaire (PHQ-9) was used to assess DS. The association of DS (PHQ-9 ≥ 10) with working hours (≤40, 41-50, 51-60, and > 60 h/week), insomnia (with or without), and interaction of both was estimated using multivariable logistic regression analysis.

RESULTS

Compared with the group working for ≤40 h/week, the adjusted odds ratios (ORs) for DS among participants who worked for 41-50 h/week, 51-60 h/week, and > 60 h/week were 1.32 (1.11-1.56), 1.74 (1.35-2.24), and 2.54 (1.90-3.39), respectively. The ORs for DS among those with insomnia were 2.36 (2.04-2.74) after adjusting for general characteristics. The ORs for DS related to insomnia were similar [1.91 (1.46-2.50), 2.00 (1.61-2.50), respectively] in the participants who worked for < 50 h/week. However, among participants working for 51-60 h or > 60 h/week, the adjusted ORs for DS substantially increased to 4.62 (2.90-7.37) and 5.60 (3.36-9.33), respectively. Moreover, among the participants with insomnia, working overtime showed a greater association with DS.

CONCLUSIONS

We showed that long working hours and insomnia are independent factors associated with the prevalence of DS; furthermore, an interaction effect of long working hours and insomnia on DS was observed. For relieving DS in internet company employees, it is important to reduce insomnia.

Health and Social Inequalities in Women Living in Disadvantaged Conditions: A Focus on Gynecologic and Obstetric Health and Intimate Partner Violence

Purpose: Gynecologic and obstetric health and intimate partner violence are particularly influenced by social determinants of health, such as poverty, low education, and poor nutritional status, and by ethnic and racial factors. In this study, we evaluated health and social inequalities of women living in disadvantaged neighborhoods in the city of Rome, Italy.

Methods: The study included 128 women living in socioeconomically disadvantaged neighborhoods. For each woman, a medical record was compiled and a gynecologic examination with screening for cervical cancer was performed. Family network, risk factors for gender-based violence, and psychological abuse were also evaluated.

Results: The largest part of the sample, although had adequate schooling, was unemployed or had a low-status job; this was at the basis of intimate partner violence in about one-third of our sample. Nearly 35% of our sample was composed of pregnant women; about half of them were not assisted by the public health system for routine obstetric examinations. Common findings at gynecologic examination for nonpregnant women were infections (n=18, 19.9%), pregnancy planning (n=13, 13.7%), menopause management (n=12, 12.6%), ovarian fibromas (n=6, 6.3%), and post-partum assistance (n=3, 3.2%). Screening for cervical cancer was executed in 62 women; 9 (14.5%) had low- or high-grade squamous intraepithelial lesion or cervical carcinoma.

Conclusions: Health and social inequalities are frequent in women living in disadvantaged conditions, with serious consequences for health and quality of life of women and of their children. Prevention and treatment, especially for the most vulnerable subjects, should be a priority for the public health system.

The Impact of Work Hours on Depressive Symptoms among Koreans Aged 45 and over

Background: Given the documented importance of employment for middle-aged and older adults' mental health, studies of the association between their number of work hours and depressive symptoms are needed. Objectives: To examine the association between the number of work hours and depressive symptoms in Korean aged 45 and over. Methods: We used data from the first wave to fourth wave of the Korea Longitudinal Study of Aging. Using the first wave at baseline, data included 9845 individuals. Depressive symptoms were measured using the 10-item Center for Epidemiological Studies Depression scale. We performed a longitudinal analysis to estimate the prevalence of depressive symptoms by work hours. Results: Both unemployed males and females aged 45-65 years were associated with higher depressive symptoms (β = 0.59, p < 0.001; β = 0.32, p < 0.001). Females working ≥ 69 h were associated with higher depressive symptoms compared to those working 41-68 h (β = 0.25, p = 0.013). Among those both middle-aged and older adults, both males and females unemployed were associated with higher depressive symptoms. Those middle-aged female working ≥69 h were associated with higher depressive symptoms. Conclusions: An increase in depressive symptoms was associated with unemployed males and females working ≥69 h compared to those working 41-68 h. Although this association was found among middle-aged individuals, a decrease in depressive symptoms in both sexes was associated with working 1-40 h. Depressive symptoms should decrease by implementing employment policies and social services to encourage employers to support middle-aged and older adults in the workforce considering their sex and age differences.

Long working hours and psychiatric treatment: A Danish follow-up study

Objective:

This study aimed to estimate prospective associations between long working hours and (i) redeemed prescriptions for psychotropic drugs and (ii) psychiatric hospital treatment due to mood, anxiety or stress-related disease, among full-time employees in Denmark.

Methods:

Full-time employees who participated in the Danish Labor Force Survey sometime in the period 2000–2013 (N=131 321] were followed for up to five years in national registers for redeemed prescriptions for psychotropic drugs and psychiatric hospital treatment due to mood, anxiety or stress-related disease. Rate ratios (RR) were estimated for 41–48 versus 32–40 and >48 versus 32–40 working hours a week. The analyses were controlled for sex, age, night shift work, calendar time of the interview and socioeconomic status (SES). Prevalent cases were excluded in primary analyses.

Results:

The RR for psychotropic drugs were estimated at 0.94 [99% confidence interval (CI) 0.88–1.01] for 41–48 versus 32–40 working hours a week and 1.08 (99% CI 0.99–1.18) for >48 versus 32–40 working hours a week. The corresponding RR for psychiatric hospital treatments were estimated at 0.90 (95% CI 0.75–1.08) and 0.96 (95% CI 0.76–1.21). We did not find any statistically significant interaction between weekly working hours and age, sex, SES or night shift work.

Conclusion:

Long working hours as they occur in in the general working population of Denmark are not an important predictor of mental ill health.