Effect of the Interaction Between Employment Level and Psychosocial Work Environment on Insomnia in Male Japanese Public Service Workers

Gene‒environment interaction effect of hypothalamic‒pituitary‒adrenal axis gene polymorphisms and job stress on the risk of sleep disturbances

Background

Studies have shown that chronic exposure to job stress may increase the risk of sleep disturbances and that hypothalamic‒pituitary‒adrenal (HPA) axis gene polymorphisms may play an important role in the psychopathologic mechanisms of sleep disturbances. However, the interactions among job stress, gene polymorphisms and sleep disturbances have not been examined from the perspective of the HPA axis. This study aimed to know whether job stress is a risk factor for sleep disturbances and to further explore the effect of the HPA axis gene × job stress interaction on sleep disturbances among railway workers.

Methods

In this cross-sectional study, 671 participants (363 males and 308 females) from the China Railway Fuzhou Branch were included. Sleep disturbances were evaluated with the Pittsburgh Sleep Quality Index (PSQI), and job stress was measured with the Effort-Reward Imbalance scale (ERI). Generalized multivariate dimensionality reduction (GMDR) models were used to assess gene‒environment interactions.

Results

We found a significant positive correlation between job stress and sleep disturbances (P < 0.01). The FKBP5 rs1360780-T and rs4713916-A alleles and the CRHR1 rs110402-G allele were associated with increased sleep disturbance risk, with adjusted ORs (95% CIs) of 1.75 [1.38-2.22], 1.68 [1.30-2.18] and 1.43 [1.09-1.87], respectively. However, the FKBP5 rs9470080-T allele was a protective factor against sleep disturbances, with an OR (95% CI) of 0.65 [0.51-0.83]. GMDR analysis indicated that under job stress, individuals with the FKBP5 rs1368780-CT, rs4713916-GG, and rs9470080-CT genotypes and the CRHR1 rs110402-AA genotype had the greatest risk of sleep disturbances.

Conclusions

Individuals carrying risk alleles who experience job stress may be at increased risk of sleep disturbances. These findings may provide new insights into stress-related sleep disturbances in occupational populations.

Socioeconomic status and sleep health: a narrative synthesis of 3 decades of empirical research

STUDY OBJECTIVES

This review aims to assess the association between socioeconomic status (SES) and sleep health in the general population and the mediating effects of lifestyle and mental and physical health in this relationship.

METHODS

Observational studies testing the independent association between objective or subjective SES indicators and behavioral/physiological or clinical sleep health variables in the general population were included. PubMed/MEDLINE was searched for reports published from January 1990 to December 2019. The direction of effect was used as the primary effect measure, testing the hypothesis that low SES is associated with poor sleep health outcomes. Results are presented in the form of direction effect plots and synthesized as binomial proportions.

RESULTS

Overall, 336 studies were identified. A high proportion of effects at the expected direction was noted for measures of sleep continuity (100% for sleep latency, 50-100% for awakenings, 66.7-100% for sleep efficiency), symptoms of disturbed sleep (75-94.1% for insomnia, 66.7-100% for sleep-disordered breathing, 60-100% for hypersomnia), and general sleep satisfaction (62.5-100%), while the effect on sleep duration was inconsistent and depended on the specific SES variable (92.3% for subjective SES, 31.7% for employment status). Lifestyle habits, chronic illnesses, and psychological factors were identified as key mediators of the SES-sleep relationship.

CONCLUSIONS

Unhealthy behaviors, increased stress levels, and limited access to health care in low-SES individuals may explain the SES-sleep health gradient. However, the cross-sectional design of most studies and the high heterogeneity in employed measures of SES and sleep limit the quality of evidence. Further research is warranted due to important implications for health issues and policy changes.

CITATION

Papadopoulos D, Etindele Sosso FA. Socioeconomic status and sleep health: a narrative synthesis of 3 decades of empirical research. J Clin Sleep Med. 2023;19(3):605-620.

Examining the impact of employment status on sleep quality during the COVID-19 pandemic in two low-income neighborhoods in Pittsburgh, PA

STUDY OBJECTIVES

African Americans have faced disproportionate socioeconomic and health consequences associated with the COVID-19 pandemic. The current study examines employment and its association with sleep quality during the initial months of the pandemic in a low-income, predominantly African American adult sample.

METHODS

In the early months of COVID-19 (March to May 2020), we administered a survey to an ongoing, longitudinal cohort of older adults to assess the impact of COVID-related changes in employment on self-reported sleep quality (N = 460; 93.9% African American). Participants had prior sleep quality assessed in 2018 and a subset also had sleep quality assessed in 2013 and 2016. Primary analyses focused on the prevalence of poor sleep quality and changes in sleep quality between 2018 and 2020, according to employment status. Financial strain and prior income were assessed as moderators of the association between employment status and sleep quality. We plotted trend lines showing sleep quality from 2013 to 2020 in a subset (n = 339) with all four waves of sleep data available.

RESULTS

All participants experienced increases in poor sleep quality between 2018 and 2020, with no statistical differences between the employment groups. However, we found some evidence of moderation by financial strain and income. The trend analysis demonstrated increases in poor sleep quality primarily between 2018 and 2020.

CONCLUSIONS

Sleep quality worsened during the pandemic among low-income African American adults. Policies to support the financially vulnerable and marginalized populations could benefit sleep quality.

The Association Between Morningness-Eveningness Preference, Depression, Anxiety and Insomnia Among Chinese Textile Workers With or Without Shift Work

OBJECTIVE

Circadian preference and mental health disorders are closely related to insomnia. This study aimed to evaluate insomnia symptoms in textile factory workers with different work schedules, and to investigate the association between insomnia, morningness-eveningness preference, anxiety, and depression.

METHODS

A total of 3,883 textile workers were assessed using the 3-items of Pittsburg Sleep Quality Index, Composite Scale of Morningness, Beck Anxiety Inventory, Center for Epidemiologic Studies-Depression Scale, and socio-demographic questionnaires.

RESULTS

The prevalence rate of insomnia in textile workers was 16.7% (N = 646), with 49.8% (N = 322) were shift workers. Among shift workers (N = 1,833), 9.5% had difficulty initiating sleep, and almost 9.0% suffered from early morning awakening, a rate significantly higher than among daytime workers. Logistics regressions revealed that work schedule was insignificantly associated with insomnia. Depression (OR = 1.034, 95% CI = 1.022-1.046) and anxiety (OR = 1.031, 95% CI = 1.018-1.043) positively predicted insomnia, whereas morningness preference (OR = 0.977, 95% CI = 0.960-0.995) decreased the likelihood of insomnia. Furthermore, mediation analysis showed that both anxiety and depression independently mediated the association between circadian preferences and insomnia in textile workers with or without shift work.

CONCLUSION

This study highlighted the insomnia, depression, and anxiety of textile factory workers in a Chinese textile factory. To improve insomnia symptoms, interventions to promote morningness circadian preference and reduce depressive and anxious symptoms among workers are encouraged.

Insomnia Associated with Tinnitus and Gender Differences

Chronic tinnitus causes a decrease in well-being and can negatively affect sleep quality. It has further been indicated that there are clinically relevant gender differences, which may also have an impact on sleep quality. By conducting a retrospective and explorative data analysis for differences in patients with tinnitus and patients diagnosed with tinnitus and insomnia, hypothesized differences were explored in the summed test scores and on item-level of the validated psychometric instruments. A cross-sectional study was conducted collecting data from a sample of tinnitus patients (n = 76). Insomnia was diagnosed in 49 patients. Gender differences were found on aggregated test scores of the MADRS and BDI with men scoring higher than women, indicating higher depressive symptoms in men. Women stated to suffer more from headaches (p < 0.003), neck pain (p < 0.006) and nervousness as well as restlessness (p < 0.02). Women also reported an increase in tinnitus loudness in response to stress compared to men (p < 0.03). Male individuals with tinnitus and insomnia have higher depression scores and more clinically relevant depressive symptoms than women, who suffer more from psychosomatic symptoms. The results indicate a need for a targeted therapy of depressive symptoms in male patients and targeted treatment of psychosomatic symptoms, stress-related worsening of insomnia and tinnitus in women.

Analysis of the evidence of related factors, associated conditions and at-risk populations of the NANDA-I nursing diagnosis insomnia

Objectives

To summarize evidence in the literature on the predictors of insomnia in adults and to determine correspondences with diagnostic indicators of the NANDA-I diagnosis Insomnia.

Methods

An integrative review performed in Pubmed, Virtual Health Library and CINAHL. Forty-eight articles published in Portuguese, English or Spanish from 2011 to 2018 were included. An analysis of correspondence between the predictors and the NANDA-I related factors and associated conditions for Insomnia was performed.

Results

There was a correspondence of the predictors found in this review with NANDA-I related factors and associated conditions, except for grieving and frequent naps during the day. Smoking, caffeine intake, dysfunctional sleep beliefs, obesity and caregiver role strain are possible new related factors; chronic illness is a possible new associated condition and individuals going through changes in marital status, economically disadvantaged, female gender, increasing age and night shift worker are possible new at-risk populations.

Conclusion

The predictors of insomnia that had a correspondence with the NANDA-I elements can support the evidence base of the nursing diagnosis. The predictors found without a correspondence with the diagnosis can be considered for inclusion in the NANDA-I classification, thereby supporting the clinical reasoning of nurses and students.

Shift work sleep disorder and job stress in shift nurses: implications for preventive interventions

BACKGROUND

A growing literature has revealed a relationship between shift-work, including night-shift, and the disturbance of sleep-wake cycle, leading to insomnia and/or increased daytime sleepiness in shift nurses; recent findings showed an association between shift work sleep disorders and distress, work accidents, decreased job performance and, consequently, lower quality of health service provision and lower standards of care.

OBJECTIVES

To analyze across the gender how shift nurses experience shift work sleep disorders and job stress.

METHODS

A cross-sectional study was performed following the STROBE Statement. The Italian version of the Job Content Questionnaire, the Bergen Insomnia Scale and the Epworth Sleepiness Scale were administered to the registered nurses employed in three Departments of General Practice and Elderly Care Medicine.

RESULTS

No significant association was found between high job strain and insomnia and daytime sleepiness. Significantly more women than men experienced high job strain, insomnia and daytime sleepiness; among women the level of social support was significantly and negatively associated with insomnia and daytime sleepiness.

CONCLUSIONS

The findings of this study suggest that interventions aimed to prevent shift work sleep disorder and job stress in shift-nurses should incorporate the assessment of social support across the gender. Moreover, longitudinal studies are required to evaluate the effectiveness of interventions targeted on social support to minimize the occurrence of insomnia and daytime sleepiness in shift nurses.

Mediating role of occupational stress and job satisfaction on the relationship between neuroticism and quality of life among Chinese civil servants: a structural equation model

Background

Knowledge on the quality of life (QOL) of civil servants is limited. Therefore, the aims of this study were to investigate the QOL of civil servants, and examine whether occupational stress and job satisfaction mediated the association between neuroticism and QOL in civil servants from Shandong, China.

Methods

The cross-sectional study included 559 civil servants aged 27 to 60 years from Shandong province in China. Participants completed questionnaires assessing neuroticism, occupational stress, job satisfaction, and QOL. Structural equation modeling (SEM) was conducted to examine the hypothetical model.

Results

Among the civil servants, the average score for QOL was 75.49 ± 14.73. The SEM analysis showed a good fit of the data to the hypothesized model. Neuroticism, occupational stress, and job satisfaction explained 38% of the variance of QOL. Neuroticism was positively correlated with occupational stress and negatively correlated with job satisfaction and QOL. A strong direct effect (− 0.386, P < 0.01) and moderate indirect effect (− 0.133, P < 0.01) of neuroticism on QOL mediated by occupational stress and job satisfaction were observed. In addition, a direct effect (− 0.197, P < 0.01) and an indirect effect (− 0.044, P < 0.01) of occupational stress on QOL mediated by job satisfaction were also observed.

Conclusions

Occupational stress and job satisfaction partly mediated the relationship between neuroticism and QOL among Chinese civil servants. Thus, selecting individuals with a low level of neuroticism as civil servants, reducing occupational stress, and increasing job satisfaction may be important measures to improve their QOL.

Association between unemployment and insomnia-related symptoms based on the Comprehensive Survey of Living Conditions: a large cross-sectional Japanese population survey

This study examined whether employment category was associated with insomnia-related symptoms (IRS). We analyzed the 2010 Comprehensive Survey of Living Conditions in Japan. The anonymous data of 43,865 people ranging from 20-59 yr of age were analyzed. We defined six employment categories: regularly employed, non-regularly employed, self-employed, others, unemployed and not in the labor force. Sex-specific odds ratios (ORs) and 95% confidence intervals (CIs) of IRS were calculated using multivariable logistic regression analysis, adjusted for confounding factors. We further conducted stratified analyses by mental illness, smoking status, and age. For men, the multivariable ORs (95% CI) of IRS for the unemployed and those who were not in the labor force were 2.5 (1.8-3.4) and 2.1 (1.2-3.7). For women, the multivariable ORs (95% CI) for the unemployed was 1.9 (1.5-2.5). After being stratified by mental illness, we found that the associations were not significant in persons with mental illness, and were more evident in persons without mental illness. Smoking and age did not modify the associations. In conclusion, we found a significantly higher OR of IRS for the unemployed, and men who were not in the labor force. These associations were particularly more evident for individuals without mental illness.

An expanded holistic model of healthy workplace practices

Purpose

The purpose of this paper is to test whether supportive workspace design, cultivation of high-quality leader–member relationships and vision alignment explain incremental variance in job satisfaction, work engagement and overall life satisfaction beyond antecedents identified in an earlier model of healthy workplace practices.

Design/methodology/approach

This paper reports the results of a survey study with a diverse sample of 214 employees.

Findings

In a series of regression analyses, the findings revealed that supportive workspace design, cultivation of high-quality leader–member relationships and vision alignment each explain incremental variance in one or more outcome variables (job satisfaction, work engagement and overall life satisfaction) beyond that of antecedents identified in an earlier model of healthy workplace practices.

Research limitations/implications

The present study identifies additional important variables to consider when conducting future research on healthy workplace practices. Future research could use longitudinal or experimental designs to further investigate the causal direction of the relationships identified in the present paper.

Practical implications

Managers can implement the practices identified in this paper to improve employees’ work engagement, job satisfaction and overall life satisfaction.

Social implications

This paper offers insights about how to improve employees’ lives, and thus, the potential impact is far-reaching and meaningful.

Originality/value

This paper empirically assesses workplace variables that were not included in tests of the prior healthy workplace practices model.

Relationships between insomnia, long working hours, and long commuting time among public school teachers in Japan: a nationwide cross-sectional diary study

OBJECTIVES

The present study aimed to clarify the prevalence and risk factors of insomnia among public school teachers in Japan by examining the relationships between working hours, commuting time, and insomnia. Time spent on work activities among teachers with insomnia was also investigated.

METHODS

This study was a secondary analysis of data obtained in a 2016 survey of working conditions among public elementary/junior high school teachers in Japan. A total of 11,390 teachers (women: 47.4%, average age: 42.2 ± 11.3 years) were selected for analysis. The relationships between working hours, commuting time, and insomnia were evaluated using a binomial logistic regression model. The primary outcome was insomnia, defined by a score of ≥6 on the Athens Insomnia Scale. Explanatory factors were working hours/week, commuting time/day, six subscales of occupational stress, age group, presence of children, type of job, type of the school, and the urbanicity of the school.

RESULTS

In total, 41.7% of men and 44.0% of women were classified into the insomnia group. The insomnia group spent more time preparing for lectures, and a significant association was observed between insomnia and long working hours and commuting time. Results of multivariate logistic regression analysis showed that long working hours, long commuting time, and urbanicity of the school were statistically significantly associated with insomnia.

CONCLUSIONS

Insomnia is common among public school teachers in Japan. Our findings suggest the importance of reducing the time spent on working to prevent insomnia.

Association between insomnia and job stress: a meta-analysis

PURPOSE

Insomnia has become one of the foremost health concerns among workers. Despite a significant number of epidemiological studies have reported on the correlation between insomnia and job stress, comprehensive evidence remains insufficient. Therefore, this research seeks to provide evidence with greater reliability, through summarizing relevant contemporary literature via a meta-analysis.

METHODS

Literature from across Europe and Asia that was of both a prospective and cross-sectional design was included, if well-controlled odds ratios were available. The meta-analysis was undertaken in accordance with the guidelines devised by PRISMA, including tests for publication bias and heterogeneity.

RESULTS

High job stress was associated with a greater risk of suffering from insomnia (random OR = 1.73, 95% CI 1.46-2.05), and the correlation between effort-reward imbalance and insomnia was statistically significant (random OR = 2.63, 95% CI 1.22-5.69). Higher demand was correlated to a relatively greater risk of insomnia (random OR = 1.35, 95% CI 1.20-1.51), while the pooled effect of low control was not found to be statistically significant. The summary random odds ratio of heavy workload was 2.76, and a pooled odds ratio of 1.67 (fixed, 95% CI 1.11-2.52) was calculated in low social support. With regard to the overall population, work-family conflict was correlated with insomnia (random OR = 2.32, 95% CI 1.53-3.51). The subgroup analysis provided comparable outcomes, for both males (fixed OR = 1.97, 95% CI 1.50-2.57) and females (random OR = 2.80, 95% CI 1.30-6.05). Egger's regression indicated that publication bias may be apparent in the syntheses of effort-reward imbalance, low social support, and work-family conflict (p < 0.05). Heterogeneity was caused by design, measuring the exposure or outcome, in addition to the region where the research was conducted.

CONCLUSIONS

The correlation between insomnia and higher levels of job stress, effort-reward imbalance, high demand, heavy workload, and low social support was determined. Publication bias and heterogeneity were partially observed. Furthermore, future studies with improved methodologies and a focus on mechanisms are anticipated.

Relationship between Job Stress and 5-HT2A Receptor Polymorphisms on Self-Reported Sleep Quality in Physicians in Urumqi (Xinjiang, China): A Cross-Sectional Study

The serotonin receptor (5-HTR) plays a key role in sleep quality regulation. Job-related stress is an important factor that influences sleep quality. However, few reports on the interaction between 5-HTR2A polymorphisms and job stress, and how they may impact upon sleep quality are available. Therefore this study investigated the effects of job stress, 5-HTR2A polymorphisms, and their interaction on sleep quality, in physicians. Using a two-stage stratified sampling method, 918 participants were initially invited to participate in the study. After screening for study inclusion and exclusion criteria, 504 subjects were eventually included in the study. Job stress and sleep quality were assessed using the Job Stress Survey (JSS) and Pittsburgh Sleep Quality Index (PSQI), respectively. The 5-HTR2A receptor gene polymorphisms T102C and -1438G/A of were determined using polymerase chain reaction-restriction fragment length polymorphism. Job stress was significantly associated with sleep quality. High levels of job stress were linked to a higher risk of poor sleep quality compared to low or moderate levels [odds ratio (OR) = 2.909, 95% confidence interval (CI): 1.697–4.986]. High levels of stress may reduce subjects’ sleep quality, leading to an increase the likelihood of sleep disturbances and subsequent daytime dysfunction. The 5-HTR2A receptor gene polymorphism T102C was not significantly associated with sleep quality in this study, however, the -1438G/A polymorphism was significantly associated with sleep quality. The GG genotype of the -1438G/A polymorphism was linked to poorer sleep quality. When compared with subjects with low job-related stress levels×AG/AA genotype (OR = 2.106, 95% CI: 1.278–3.471), physicians with high job-related stress levels×GG genotype had a higher risk of experiencing poor sleep quality (OR = 13.400, 95% CI: 3.143–57.137). The findings of our study indicate that job stress and 5-HTR2A receptor gene polymorphisms are associated with sleep quality in physicians. Subjects with high job stress level or/and the -1438G/A GG genotype were more likely to report poor sleep quality, and furthermore, their combination effect on sleep quality was higher than their independent effects, so it may be suggested that job-related stress and genes have a cumulative effect on sleep quality; that is, stress can increase the risk of poor sleep quality, but this effect is worse in a group of people with specific gene polymorphisms.

Relationships between temperaments, occupational stress, and insomnia among Japanese workers

Insomnia among workers reduces the quality of life, contributes toward the economic burden of healthcare costs and losses in work performance. The relationship between occupational stress and insomnia has been reported in previous studies, but there has been little attention to temperament in occupational safety and health research. The aim of this study was to clarify the relationships between temperament, occupational stress, and insomnia. The subjects were 133 Japanese daytime local government employees. Temperament was assessed using the Temperament Evaluation of Memphis, Pisa, Paris, and San Diego-Auto questionnaire (TEMPS-A). Occupational stress was assessed using the Generic Job Stress Questionnaire (GJSQ). Insomnia was assessed using the Athens Insomnia Scale (AIS). Stepwise multiple logistic regression analyses were conducted. In a stepwise multivariate logistic regression analysis, it was found that the higher subdivided stress group by “role conflict” (OR = 5.29, 95% CI, 1.61–17.32) and anxious temperament score (OR = 1.33; 95% CI, 1.19–1.49) was associated with the presence of insomnia using an adjusted model, whereas other factors were excluded from the model. The study limitations were the sample size and the fact that only Japanese local government employees were surveyed. This study demonstrated the relationships between workers’ anxious temperament, role conflict, and insomnia. Recognizing one’s own anxious temperament would lead to self-insight, and the recognition of anxious temperament and reduction of role conflict by their supervisors or coworkers would reduce the prevalence of insomnia among workers in the workplace.

Job Strain and Self-Reported Insomnia Symptoms among Nurses: What about the Influence of Emotional Demands and Social Support?

Job strain, derived from high psychological demands and low job control, is associated with insomnia, but information on the role of emotional demands and social support in this relationship is scarce. The aims of this study were (i) to test the association between job strain and self-reported insomnia symptoms, (ii) to evaluate the combination of emotional demands and job control regarding insomnia symptoms, and (iii) to analyze the influence of social support in these relationships. This cross-sectional study refers to a sample of nurses (N = 3,013 and N = 3,035 for Job Strain and Emotional demand-control model, resp.) working at public hospitals in Rio de Janeiro, Brazil. Data were collected through a self-report questionnaire. The prevalence of insomnia symptoms was 34.3%. Job strain was associated with increased odds for insomnia symptoms (OR: 2.20); the same result was observed with the combination of emotional demands and low job control (OR: 1.99). In both models, the inclusion of low social support combined with high demands and low job control led to increased odds for insomnia symptoms, compared to groups with high social support from coworkers and supervisors. Besides job strain, the study of emotional demands and social support are promising with regards to insomnia symptoms, particularly among nurses.

The association of insomnia with gastroesophageal reflux symptoms in biopsy-proven nonalcoholic fatty liver disease

BACKGROUND

It is suggested that nonalcoholic fatty liver disease (NAFLD), including nonalcoholic fatty liver (NAFL) and nonalcoholic steatohepatitis (NASH), can be associated with insomnia and gastro-esophageal reflux disease (GERD). The relationship between GERD and insomnia in subjects with biopsy-proven NAFLD was investigated.

METHODS

This study enrolled 123 patients with biopsy-proven NAFLD. Insomnia was assessed by the Athens Insomnia Scale (AIS), a self-assessment psychometric instrument designed to quantify sleep difficulty based on ICD-10 criteria; AIS scores ≥ 6 were considered positive for insomnia. GERD symptoms were evaluated using a frequency scale for the symptoms of GERD (FSSG); FSSG scores ≥ 8 were considered positive. Logistic regression models were used to evaluate the association of insomnia with GERD, after adjusting for potential confounders. Thirteen patients with GERD were treated with the proton pump inhibitor rabeprazole (RPZ; 10 mg/day), for 12 weeks.

RESULTS

Of the 123 patients, 76 (62%) were female and 87 (71%) were obese, with 34 (28%) having AIS scores ≥ 6 and 31 (25%) having FSSG scores ≥ 8. Liver biopsy revealed that 40 patients (33%) had NAFL and 83 (67%) had NASH. FSSG and AIS scores were similar in the two groups. HOMA-IR, FSSG scores and γGT (GGT) concentrations were significantly higher in insomniacs than in non-insomniacs. Logistic regression analysis demonstrated that FSSG score and GGT concentration were independently associated with insomnia. RPZ treatment resulted in significantly reductions in both AIS and FSSG scores.

CONCLUSIONS

Nearly 30% of patients with biopsy-proven NAFLD had insomnia, which was related to GGT and GERD and could be relieved by RPZ treatment.