Incidence of coronary heart disease among remote workers: a nationwide web-based cohort study

Coronary heart disease (CHD) risk is influenced by socioeconomic status-related parameters, particularly occupation. We investigated occupational gaps in CHD risk and how the introduction of remote work moderated the observed occupational differences in CHD risk during the coronavirus disease 2019 pandemic in Japan. Data from a web-based, nationwide cohort study, comprising 17,640 workers (aged 20-65 years) with baseline data from December 2020, were analyzed. Participants were grouped by occupation as upper-level nonmanual workers (managers/professionals) and others (reference group). The primary outcome was CHD (angina pectoris/myocardial infarction) onset retrospectively confirmed at the 1-year follow-up survey. Upper-level nonmanual workers exhibited a higher CHD incidence than others (2.3% vs. 1.7%). This association was pronounced in the younger (20-49 years) population, with a significant CHD risk (adjusted risk ratio = 1.88). Upper-level nonmanual workers exhibited nearly 15% higher remote work prevalence, with a significant remote work-related CHD risk (adjusted risk ratio = 1.92). The mediating effects of remote work explained an overall disparity of 32% among the younger population. Occupational gaps in CHD incidence in Japan differ from those in Western countries, where upper-level nonmanual workers have lower cardiovascular risk. In Japan, remote work can mediate CHD risk in the younger population of upper-level nonmanual workers.

Extracting immunological and clinical heterogeneity across autoimmune rheumatic diseases by cohort-wide immunophenotyping

OBJECTIVE

Extracting immunological and clinical heterogeneity across autoimmune rheumatic diseases (AIRDs) is essential towards personalised medicine.

METHODS

We conducted large-scale and cohort-wide immunophenotyping of 46 peripheral immune cells using Human Immunology Protocol of comprehensive 8-colour flow cytometric analysis. Dataset consisted of >1000 Japanese patients of 11 AIRDs with deep clinical information registered at the FLOW study, including rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). In-depth clinical and immunological characterisation was conducted for the identified RA patient clusters, including associations of inborn human genetics represented by Polygenic Risk Score (PRS).

RESULTS

Multimodal clustering of immunophenotypes deciphered underlying disease-cell type network in immune cell, disease and patient cluster resolutions. This provided immune cell type specificity shared or distinct across AIRDs, such as close immunological network between mixed connective tissue disease and SLE. Individual patient-level clustering dissected patients with AIRD into several clusters with different immunological features. Of these, RA-like or SLE-like clusters were exclusively dominant, showing immunological differentiation between RA and SLE across AIRDs. In-depth clinical analysis of RA revealed that such patient clusters differentially defined clinical heterogeneity in disease activity and treatment responses, such as treatment resistance in patients with RA with SLE-like immunophenotypes. PRS based on RA case-control and within-case stratified genome-wide association studies were associated with clinical and immunological characteristics. This pointed immune cell type implicated in disease biology such as dendritic cells for RA-interstitial lung disease.

CONCLUSION

Cohort-wide and cross-disease immunophenotyping elucidate clinically heterogeneous patient subtypes existing within single disease in immune cell type-specific manner.

A prospective cohort study of presenteeism and increased risk of unemployment among Japanese workers during the COVID-19 pandemic

OBJECTIVES

Presenteeism adversely affects workers' quality of life, leading to further deterioration of their health and affecting their ability to continue working. Unemployment is one of the most serious consequences for workers experiencing presenteeism. A worker's ability to work depends on the degree of mismatch between their health status and job demands and work factors. The COVID-19 pandemic has affected workers' experiences of presenteeism as well as their employment status. We examined the association between presenteeism and risk of job resignations and unemployment among Japanese workers during the COVID-19 pandemic.

METHODS

A prospective study of 27 036 internet monitors was conducted, starting in December 2020, with 18 560 (68.7%) participating in the follow-up by December 2021. The Work Functioning Impairment Scale (WFun) was used to measure the degree of work function impairment.

RESULTS

The group with the highest WFun scores had higher odds ratios (ORs) for both retirement and unemployment for health reasons than the group with the lowest WFun scores. ORs were 2.99 (95% CI, 2.48-3.62; P < .001) and 1.82 (95% CI, 1.65-2.00; P < .001), respectively.

CONCLUSIONS

Workers with work functioning impairment are at increased risk of resignation or unemployment. Management strategies for workers with work functioning impairment are needed to reduce their disadvantages in employment.

Association between lifestyle habits and presenteeism

BACKGROUND

Presenteeism is affected by work-related and individual factors. Among individual factors, the effect of combining various lifestyle habits on presenteeism is unknown.

AIMS

This study aimed to determine the relationship between changes in multiple good lifestyle habits with a change in presenteeism and to examine the effect of psychological factors on this relationship.

METHODS

We performed a 1-year retrospective cohort study on employees of large Japanese companies. Data were collected from health check-ups and a self-administered questionnaire. Changes in presenteeism were measured using the Quality and Quantity method. Changes in lifestyle habits were measured using a modified form of Breslow's seven health practices. Psychological factors were measured using the Kessler 6-Item Psychological Distress Scale. Linear regression was used for statistical analysis.

RESULTS

The number of practised lifestyle habit changes was negatively correlated with a change in presenteeism. This result was consistent when adjusted for age, sex and company (B, -0.010; P < 0.05), but became non-significant when additionally adjusted for psychological distress (B, -0.006). When analysed separately, only an improvement in the body mass index (B, -0.054; P < 0.05) and a worsened sleep habit (B, 0.040; P < 0.01) influenced a change in presenteeism.

CONCLUSIONS

This study suggests that improving various practised lifestyle habits in combination, rather than improving a single lifestyle habit, is beneficial in reducing presenteeism. Our finding that psychological distress altered the relationship of practised lifestyle habit changes with presenteeism indicates the importance of organizational-level intervention in presenteeism.

Inequality in workplace support for various types of precarious workers compared with permanent workers in Japan: A cross-sectional study

OBJECTIVES

The purpose of this study was to examine, by sex, whether precarious workers in Japan receive less support in the workplace than permanent workers.

METHODS

We conducted a cross-sectional study using an online questionnaire in 2022. We stratified participants by sex and performed modified Poisson regression analysis. The outcomes were support from supervisors, co-workers, occupational health professionals, and no one. Adjusted prevalence ratios (aPR) were calculated for contract workers, part-time workers, and dispatched workers, using permanent workers as reference.

RESULTS

This study had 21 047 participants. For men, 87.9% were permanent workers; for women, 50.7% were permanent workers and 37.3% were part-time workers. For workplace support, 47.5% of men and 45.2% of women selected superiors; 41.8% of men and 50.5% of women selected colleagues; 16.8% of men and 6.2% of women selected occupational health professionals. Female contract workers were less likely to receive support from their supervisors (aPR 0.88) or co-workers (aPR 0.89). Male part-time workers were less likely to be supported by their co-workers (aPR 0.86). Dispatched workers were less likely to be supported by their supervisors (men aPR 0.71, women aPR 0.84) and co-workers (men aPR 0.73, women aPR 0.77). Part-time and dispatched workers were less likely to receive support from occupational health professionals.

CONCLUSIONS

Precarious workers could get less workplace support than permanent workers. This may contribute to occupational health problems with precarious workers.

Job stress among workers who telecommute during the coronavirus disease (COVID-19) pandemic in Japan: a cross-sectional study

OBJECTIVES

The work system reform and the COVID-19 pandemic in Japan have prompted efforts toward telecommuting in Japan. However, only a few studies have investigated the stress and health effects of telecommuting. Therefore, this study aimed to clarify the relationship between telecommuting and job stress among Japanese workers.

MATERIAL AND METHODS

This was a cross-sectional study. In December 2020, during the "third wave" of the COVID-19 pandemic, an Internet-based nationwide health survey of 33 087 Japanese workers (The Collaborative Online Research on Novel-coronavirus and Work, CORoNaWork study) was conducted. Data of 27 036 individuals were included after excluding 6051 invalid responses. The authors analyzed a sample of 13 468 office workers from this database. The participants were classified into 4 groups according to their telecommuting frequency, while comparing scores on the subscale of the Job Content Questionnaire (JCQ) and subjective job stress between the high-frequency, medium-frequency, low-frequency, and non-telecommuters groups. A linear mixed model and an ordinal logistic regression analysis were used.

RESULTS

A significant difference in the job control scores of the JCQ among the 4 groups was found, after adjusting for multiple confounding factors. The high-frequency telecommuters group had the highest job control score. Further, after adjusting for multiple confounding factors, the subjective job stress scores of the high- and medium-frequency telecommuters groups were significantly lower than those of the non-telecommuters group.

CONCLUSIONS

This study revealed that high-frequency telecommuting was associated with high job control and low subjective job stress. The widespread adoption of telecommuting as a countermeasure to the public health challenges associated with the COVID-19 pandemic may also have a positive impact on job stress. Int J Occup Med Environ Health. 2022;35(3):339-51.

Effect of commuting on the risk of COVID-19 and COVID-19-induced anxiety in Japan, December 2020

BACKGROUND

To prevent the spread of coronavirus disease (COVID-19), it is important to avoid 3Cs (closed spaces, crowded places, and close-contact settings). However, the risk of contact with an unspecified number of people is inevitable while commuting to and from work. In this study, we investigated the relationship between commuting, and the risk of COVID-19 and COVID-19-induced anxiety.

METHODS

An internet-based questionnaire survey was conducted to obtain a dataset from 27,036 respondents. One-way commuting time was evaluated using a five-case method. The commuting distance was estimated using zip codes of the home and workplace. Logistic regression analysis was performed with the following outcomes: COVID-19 risk, close contact, infection anxiety, and infection anxiety due to commuting. Commuting distance and commuting time were analyzed separately in the model. We excluded participants with incalculable commuting distance, commuting distance exceeding 300 km, commuting distance of 0 km, or who telecommuted at least once a week.

RESULTS

The total number of participants included in the analysis was 14,038. The adjusted odds ratios (aORs) of using public transportation for severe acute respiratory syndrome coronavirus 2 infection were 4.17 (95% confidence interval [CI]: 2.51-6.93) (commuting time) and 5.18 (95% CI: 3.06-8.78) (commuting distance). The aOR of COVID-19 diagnosis decreased significantly with increasing commuting distance. The aORs of using public transportation to infection anxiety were 1.44 (95% CI: 1.31-1.59) (commuting time) and 1.45 (95% CI: 1.32-1.60) (commuting distance). The longer the commuting time, the more the aOR increased.

CONCLUSIONS

COVID-19 risk, close contact, and infection anxiety were all associated with the use of public transportation during commuting. Both commuting distance and time were associated with infection anxiety due to commuting, and the strength of the association increased with increase in commuting time distance. Since transportation by commuting is associated with COVID-19 risk and anxiety, we recommend the use of telecommuting and other means of work.

Industry and workplace characteristics associated with the downloading of a COVID-19 contact tracing app in Japan: a nation-wide cross-sectional study

BACKGROUND

To combat coronavirus disease 2019 (COVID-19), many countries have used contact tracing apps, including Japan's voluntary-use contact-confirming application (COCOA). The current study aimed to identify industry and workplace characteristics associated with the downloading of this COVID-19 contact tracing app.

METHODS

This cross-sectional study of full-time workers used an online survey. Multiple logistic regression analysis was used to evaluate the associations of industry and workplace characteristics with contact tracing app use.

RESULTS

Of the 27,036 participants, 25.1% had downloaded the COCOA. Workers in the public service (adjusted odds ratio [aOR] = 1.29, 95% confidence interval [CI] 1.14-1.45) and information technology (aOR = 1.38, 95% CI 1.20-1.58) industries were more likely to use the app than were those in the manufacturing industry. In contrast, app usage was less common among workers in the retail and wholesale (aOR = 0.87, 95% CI 0.76-0.99) and food/beverage (aOR = 0.81, 95% CI 0.70-0.94) industries, but further adjustment for company size attenuated these associations. Workers at larger companies were more likely to use the app. Compared with permanent employees, the odds of using the app were higher for managers and civil servants but lower for those who were self-employed.

CONCLUSIONS

Downloading of COCOA among Japanese workers was insufficient; thus, the mitigating effect of COCOA on the COVID-19 pandemic is considered to be limited. One possible reason for the under-implementation of the contact tracing app in the retail and wholesale and food/beverage industries is small company size, as suggested by the fully adjusted model results. An awareness campaign should be conducted to promote the widespread use of the contact tracing app in these industries.

A cross-sectional study on perceived workplace health support and health-related quality of life

OBJECTIVE

Many companies in Japan have been increasingly interested in "health and productivity management (H&PM)." In terms of H&PM, we hypothesized that companies can enhance their employees' perceived workplace health support (PWHS) by supporting workers' lively working and healthy living. This could then improve their health-related quality of life (HRQOL) by increasing PWHS. Consequently, this study explored the relationship between PWHS and HRQOL.

METHODS

In December 2020, during the COVID-19 pandemic, we conducted an Internet-based nationwide health survey of Japanese workers (CORoNaWork study). A database of 27 036 participants was created. The intensity of PWHS was measured using a four-point Likert scale. We used multilevel ordered logistic regression to analyze the relationship between PWHS intensity and the four domains of the Centers for Disease Control's HRQOL-4 (self-rated health, number of poor physical health days, number of poor mental health days, and activity limitation days during the past 30 days).

RESULTS

In the sex- and age-adjusted and multivariate models, the intensity of PWHS significantly affected self-rated health and the three domains of unhealthy days (physical, mental, and activity limitation). There was also a trend toward worse HRQOL scores as the PWHS decreased.

CONCLUSIONS

We found that the higher the PWHS of Japanese workers, the higher their self-rated health and the fewer their unhealthy days. Companies need to assess workers' PWHS and HRQOL and promote H&PM. H&PM is also necessary to maintain and promote the health of workers during the COVID-19 pandemic.

Workplace measures against COVID-19 during the winter third wave in Japan: Company size-based differences

OBJECTIVES

Little is known about workplace measures against coronavirus disease 2019 (COVID-19) in Japan during the winter of 2020, especially in micro-, small-, and medium-sized enterprises (MSMEs). This study aimed to provide an overview of the current situation of anti-COVID-19 measures in Japanese enterprises during the winter, considering company size.

METHODS

This study was an Internet-based nationwide cross-sectional study. Individuals who were registered as full-time workers were invited to participate in the survey. Data were collected using an online self-administered questionnaire in December 2020. The chi-squared test for trend was performed to calculate the P-value for trend for each workplace measure across company sizes.

RESULTS

For the 27 036 participants, across company sizes, the most prevalent workplace measure was encouraging mask wearing at work, followed by requesting that employees refrain from going to work when ill and restricting work-related social gatherings and entertainment. These measures were implemented by approximately 90% of large-scale enterprises and by more than 40% of micro- and small-scale enterprises. In contrast, encouraging remote working was implemented by less than half of large-scale enterprises and by around 20% of micro- and small-scale enterprises. There were statistically significant differences in all workplace measures by company size (all P < .001).

CONCLUSIONS

We found that various responses to COVID-19 had been taken in workplaces. However, some measures, including remote working, were still not well-implemented, especially in smaller enterprises. The findings suggest that occupational health support for MSMEs is urgently needed to mitigate the current wave of COVID-19.