Associations of Extrinsic and Intrinsic Components of Work Stress with Health: A Systematic Review of Evidence on the Effort-Reward Imbalance Model

The salivary alpha amylase awakening response is related to over-commitment

We assessed the relationship between physiological and psychological measures of workplace stress as measured by the effort-reward imbalance (ERI) model, with a seldom studied sample of owner-operator dairy farmers. Dairy farmers (N = 74) self-reported ERI, over-commitment (OC), dedication, and health then provided awakening saliva samples that were used to calculate the salivary alpha amylase awakening response (sAA-AR), cortisol awakening response (CAR), and salivary immunoglobulin A (sIgA) level. ERI, OC, and dedication levels were not related with sIgA or the CAR, but more over-committed farmers had a less pronounced sAA-AR. OC was more associated than ERI with the physiological indicators of stress, potentially due to the owner-operator sample used in this investigation. The suitability of sAA as a viable physiological measure of autonomic nervous system activity has been debated, but our findings promote its inclusion in future occupational stress research.

Medical Surveillance, Continuous Health Promotion and a Participatory Intervention in a Small Company

The workplace is an ideal setting for health promotion. The regular medical examination of workers enables us to screen for numerous diseases, spread good practices and correct lifestyles, and obtain a favourable risk/benefit ratio. The continuous monitoring of the level of workers' wellbeing using a holistic approach during medical surveillance enables us to promptly identify problems in work organisation and the company climate. Problems of this kind can be adequately managed by using a participatory approach. The aim of this paper is twofold: to signal this way of proceeding with medical surveillance, and to describe an organisational development intervention. Participatory groups were used to improve occupational life in a small company. After intervention we observed a reduction in levels of perceived occupational stress measured with the Effort/Reward Imbalance questionnaire, and an improvement in psychological wellbeing assessed by means of the Goldberg Anxiety/Depression scale. Although the limited size of the sample and the lack of a control group call for a cautious evaluation of this study, the participatory strategy proved to be a useful tool due to its cost-effectiveness.

Sedentary Behaviour and Hair Cortisol Amongst Women Living in Socioeconomically Disadvantaged Neighbourhoods: A Cross-Sectional Study

Women living in socioeconomically disadvantaged neighbourhoods are at heightened risk of experiencing psychological stress. Therefore, identifying potential risk factors for stress is important to support positive mental health. A growing body of research has linked sedentary behaviour with mental ill-health (e.g., depression and anxiety); however, little research has specifically investigated potential linkages between sedentary behaviour and stress. Therefore, the aim of this study was to investigate the association between common types of sedentary behaviour and objectively-measured stress (as measured by hair cortisol levels) amongst women living in socioeconomically disadvantaged neighbourhoods. During 2012-2013, 72 women (aged 18-46 years) living in socioeconomically disadvantaged neighbourhoods self-reported sedentary behaviour (TV viewing, computer use, overall sitting time) and provided hair samples. Hair cortisol levels were measured using enzyme-linked immunosorbent assay. Linear regression models examined cross-sectional associations between sedentary behaviour and hair cortisol levels. There was no association between any type of sedentary behaviour (TV viewing, computer use, or overall sitting time) and hair cortisol levels in either crude or adjusted models. Sedentary behaviour may not be linked to hair cortisol level (stress) in women living in socioeconomically disadvantaged neighbourhoods. Further studies utilising objective measures of both sedentary behaviour and stress are required to confirm these findings.

A Systematic Review and Meta-analysis of the Effort-Reward Imbalance Model of Workplace Stress and Hypothalamic-Pituitary-Adrenal Axis Measures of Stress

OBJECTIVE

The association between effort-reward imbalance (ERI) and various health outcomes has been well documented over the past 20 years, but the mechanisms responsible for this association remain unclear. The present meta-analysis assessed the associations of ERI and overcommitment (OC) in the workplace with hypothalamic-pituitary-adrenal (HPA) axis measures.

METHODS

Electronic databases were searched with the phrase "effort*reward*imbalance," which yielded 319 studies leading to 56 full-text studies being screened. Thirty-two studies within 14 articles met inclusion criteria and were meta-analyzed using mixed and random effects models.

RESULTS

Greater ERI was associated with increased HPA axis activity (r = .09, p < .001, k = 14, N = 2541). The cortisol awakening response (r = .14, p < .001, k = 9, N = 584) and cortisol waking concentrations (r = .12, p = .01, k = 6, N = 493) were the only HPA measures associated with ERI. OC was also associated with greater HPA axis activity (r = .06, p < .01, k = 10, N = 1918). Cortisol (PM) (r = .13, p = .02, k = 3, N = 295) was the only HPA measure associated with OC.

CONCLUSIONS

ERI and OC were similarly related with HPA responsivity. However, because OC moderated the relationship between ERI and HPA axis markers, the importance of OC should not be overlooked. Because OC is likely more malleable than ERI to intervention, this may be a promising avenue for future research.

Validating the short measure of the Effort-Reward Imbalance Questionnaire in older workers in the context of New Zealand

Objectives:

The objective of this study was to validate a short version of the Effort-Reward-Imbalance (ERI) questionnaire in the context of New Zealand among older full-time and part-time employees.

Methods:

Data were collected from 1694 adults aged 48-83 years (mean 60 years, 53% female) who reported being in full- or part-time paid employment in the 2010 wave of the New Zealand Health, Work and Retirement study. Scale reliability was evaluated by item-total correlations and Cronbach's alpha. Factorial validity was assessed using multi-group confirmatory factor analyses assessing nested models of configural, metric, scalar and strict invariance across full- and part-time employment groups. Logistic regressions estimated associations of effort-reward ratio and over-commitment with poor physical/mental health, and depressive symptoms.

Results:

Internal consistency of ERI scales was high across employment groups: effort 0.78-0.76; reward 0.81-0.77, and over-commitment 0.83-0.80. The three-factor model displayed acceptable fit in the overall sample (X²/df = 10.31; CFI = 0.95; TLI = 0.94; RMSEA = 0.075), and decrements in model fit indices provided evidence for strict invariance of the three-factor ERI model across full-time and part-time employment groups. High effort-reward ratio scores were consistently associated with poor mental health and depressive symptoms for both employment groups. High over-commitment was associated with poor mental health and depressive symptoms in both groups and also with poor physical health in the full-time employment group.

Conclusions:

The short ERI questionnaire appears to be a valid instrument to assess adverse psychosocial work characteristics in old full-time and part-time employees in New Zealand.

Do Effort and Reward at Work Predict Changes in Cognitive Function? First Longitudinal Results from the Representative German Socio-Economic Panel

It has been suggested that work characteristics, such as mental demands, job control, and occupational complexity, are prospectively related to cognitive function. However, current evidence on links between psychosocial working conditions and cognitive change over time is inconsistent. In this study, we applied the effort–reward imbalance model that allows to build on previous research on mental demands and to introduce reward-based learning as a principle with beneficial effect on cognitive function. We aimed to investigate whether high effort, high reward, and low over-commitment in 2006 were associated with positive changes in cognitive function in terms of perceptual speed and word fluency (2006–2012), and whether the co-manifestation of high effort and high reward would yield the strongest association. To this end, we used data on 1031 employees who participated in a large and representative study. Multivariate linear regression analyses supported our main hypotheses (separate and combined effects of effort and reward), particularly on changes in perceptual speed, whereas the effects of over-commitment did not reach the level of statistical significance. Our findings extend available knowledge by examining the course of cognitive function over time. If corroborated by further evidence, organization-based measures in the workplace can enrich efforts towards preventing cognitive decline in ageing workforces.

Work Stress and Altered Biomarkers: A Synthesis of Findings Based on the Effort-Reward Imbalance Model

While epidemiological studies provide statistical evidence on associations of exposures such as stressful work with elevated risks of stress-related disorders (e.g., coronary heart disease or depression), additional information on biological pathways and biomarkers underlying these associations is required. In this contribution, we summarize the current state of the art on research findings linking stressful work, in terms of an established theoretical model-effort-reward imbalance-with a broad range of biomarkers. Based on structured electronic literature search and recent available systematic reviews, our synthesis of findings indicates that associations of work stress with heart rate variability, altered blood lipids, and risk of metabolic syndrome are rather consistent and robust. Significant relationships with blood pressure, heart rate, altered immune function and inflammation, cortisol release, and haemostatic biomarkers were also observed, but due to conflicting findings additional data will be needed to reach a firm conclusion. This narrative review of empirical evidence supports the argument that the biomarkers under study can act as mediators of epidemiologically established associations of work stress, as measured by effort-reward imbalance, with incident stress-related disorders.

Dissatisfaction in Child Welfare and Its Role in Predicting Self-Efficacy and Satisfaction at Work: A Mixed-Method Research

Child welfare organizations are increasingly concerned with challenges emerging from the assessment of social workers' dissatisfaction. This type of service represents the work area where social workers are at greater risk of burnout. Although several studies account for high social workers' burnout scores, they do not systematically dwell upon its sources and roots. In addition, scholars point out that a considerable number of work related issues may be perceived both as a source of dissatisfaction and satisfaction. We assume that there is a need to deepen the understanding of how dissatisfaction's sources may exert an impact on both personal job satisfaction and professional self-efficacy, which are positively associated with well-being at work. The present mixed-method research has two aims: (1) the extensive exploration, applying qualitative methodology, of the perceived sources of dissatisfaction; (2) the attempt to identify the extent to which those sources predict job satisfaction and professional self-efficacy. It is our purpose to further explore which differences emerge by age. The research involved child welfare workers, that is, SWs employed in public child welfare agencies in the North East of Italy. Results show the predominant role of interpersonal trust and mutual respect, as main predictors of both professional self-efficacy and job satisfaction. Practical implications of findings are discussed.

Long-Term Effectiveness of a Stress Management Intervention at Work: A 9-Year Follow-Up Study Based on a Randomized Wait-List Controlled Trial in Male Managers

Objective

Short- and medium-term effectiveness (up to 3 years) of individual level stress management interventions (SMI) at work were demonstrated, yet long-term effectiveness remains unexplored. We therefore aimed to address this research gap.

Methods

94 male middle managers participated in a randomized wait-list controlled trial between 2006 and 2008 and in a post-trial-follow-up survey in 2015. During the first two years, all received an 18-hour psychotherapeutic SMI intervention which was based on the Effort-Reward Imbalance (ERI) model: tackling stressor on mismatch between effort and reward and promoting recovery on overcommitment. Work stress (i.e., ERI indicators) was the primary outcome, and the secondary outcome was depressive symptoms. The long-term effectiveness of the SMI was examined by mixed modeling, using an external control group (n = 94).

Results

Effort and reward were substantially improved with significant intervention ⁎ time interaction effects (p < 0.001) compared to the external control group; effects on overcommitment and depressive symptoms were also significant (p < 0.05 and p < 0.01, resp.), though their trajectories in the intervention group were less sustainable.

Conclusions

The effectiveness of this psychotherapeutic SMI at work based on the ERI model was observed over a 9-year period, particularly on the effort-reward ratio.

The Factorial Structure and Psychometric Properties of the Persian Effort-Reward Imbalance Questionnaire

Background

With global changes in the current state of work and employment, the role of health-adverse psychosocial work environments has received increasing attention in developed as well as in rapidly developing countries. Thus, there is a need to apply valid measurement tools for monitoring and preventive purposes. This study aims to examine the factorial structure and psychometric properties of the Persian version of the effort-reward imbalance (ERI) questionnaire, assessing one of the internationally leading concepts of stressful work.

Methods

This descriptive cross-sectional study of a random sample of 202 white collar employees in an industrial company in Iran analyzes the ERI scales by exploratory and confirmatory factor analysis. Moreover, aspects of construct and criterion validity are tested. To this end, correlations of ERI scales with subscales of organizational injustice, a complementary work stress model, and also the correlations of ERI scales with a questionnaire assessing psychosomatic symptoms are performed.

Results

Internal consistency of the three ERI scales was satisfactory (Cronbach α effort: 0.76, reward: 0.79, overcommitment: 0.75). Fit indices of confirmatory factor analysis pointed to an adequate representation of the theoretical construct (e.g., adjusted goodness of fit index (AGFI): 0.73, goodness of fit index (GFI): 0.78). Negative correlations with subscales of organizational injustice supported the notion of construct validity of the ERI scales, and positive correlations of ERI scales with psychosomatic symptoms indicated preliminary criterion validity.

Conclusion

The Persian version of the ERI questionnaire has acceptable psychometric properties and can be used as a valid instrument in research on this topic.

Chronic work stress and decreased vagal tone impairs decision making and reaction time in jockeys

The inverse relationship between acute stress and decision-making is well documented, but few studies have investigated the impact of chronic stress. Jockeys work exhaustive schedules and have extremely dangerous occupations, with safe performance requiring quick reaction time and accurate decision-making. We used the effort reward imbalance (ERI) occupational stress model to assess the relationship of work stress with indices of stress physiology and decision-making and reaction time. Jockeys (N=32) completed computerised cognitive tasks (Cogstate) on two occasions; September and November (naturally occurring lower and higher stress periods), either side of an acute stress test. Higher ERI was correlated with the cortisol awakening responses (high stress r=-0.37; low stress r=0.36), and with decrements in decision-making comparable to having a blood alcohol concentration of 0.08 in the high stress period (p<0.001) The LF/HF ratio of heart rate variability impacted the association of ERI with decision-making. Potentially, this may be attributed to a 'tipping point' whereby the higher ERI reported by jockeys in the high stress period decreases vagal tone, which may contribute to reduced decision-making abilities.

Mental health among Norwegian priests: associations with effort-reward imbalance and overcommitment

PURPOSE

The aim of the study was to determine the prevalence of anxiety and depression symptoms among Norwegian priests and to examine their associations with effort-reward imbalance (ERI) and overcommitment.

METHODS

Eight hundred four priests in the Norwegian Church completed the Hospital Anxiety and Depression Scale (HADS), the Effort-Reward Imbalance Questionnaire (ERI-Q), and the Intrinsic Effort Scale, measuring overcommitment.

RESULTS

A significant proportion of the priests (23.4%) had HADS scores indicating a possible anxiety problem. Somewhat fewer had depression problems (9.3%). Both anxiety and depression difficulties were associated with an imbalance between effort given and rewards received at work. Priests characterized by a combination of this imbalance and high scores on overcommitment had more anxiety and depression symptoms.

CONCLUSIONS

There is a higher occurrence of mental health challenges among priests than among the regular population. This applies in particular to anxiety symptoms measured by the HADS. These findings also indicate that it may be fruitful to explore mental health conditions among priests who report different combinations of effort-reward and overcommitment.

Effects of psychosocial work characteristics on hair cortisol - findings from a post-trial study

Prolonged work stress, as indicated by the effort-reward imbalance (ERI) model, jeopardizes health. Cortisol represents a candidate mechanism connecting stress to ill health. However, previous findings appear inconclusive, and recommendations were made to assess work stress at multiple time points and also to investigate ERI (sub-)components. This study therefore examines the effects of two single time points, as well as the mean and change scores between time points of ERI and its components on hair cortisol concentration (HCC), a long-term cortisol measurement. Participants were 66 male factory workers (age: 40.68 ± 6.74 years; HCC: 9.00 ± 7.11 pg/mg), who were followed up after a stress management intervention (2006-2008). In 2008 (T1) and 2015 (T2), participants completed a 23-item ERI questionnaire, assessing effort, the three reward components (esteem, job security, job promotion) and over-commitment. In 2015, participants also provided a 3-cm hair segment close to the scalp for HCC analysis, as well as information on relevant confounders (i.e. medication intake, age, work characteristics, socioeconomic and lifestyle factors, number of stressful life events). Linear regressions revealed hardly any cross-sectional or longitudinal effect of ERI and its components on HCC. Only the change scores between T1 and T2 of job security were negatively associated with lower HCC in unadjusted (β = -.320; p = .009) and adjusted (β = -.288; p = .044) models. In this study, only a decrease of perceived job security over time was significantly associated with higher HCC, and other predictors were not related to this outcome. Especially after correction for multiple testing, this study revealed just a weak association of different psychosocial work measurements with HCC. Lay summary This study showed that an increase in perceived job insecurity is correlated with higher levels of the stress hormone cortisol. The higher levels of cortisol might represent a biological explanation for the negative health effects of job insecurity. The association was, however, relatively low, and more and more voices are questioning whether cortisol in hair is a reliable marker for perceived work stress.

Stress-related psychosocial factors at work, fatigue, and risky driving behavior in bus rapid transport (BRT) drivers

INTRODUCTION

There is consistent scientific evidence that professional drivers constitute an occupational group that is highly exposed to work related stressors. Furthermore, several recent studies associate work stress and fatigue with unsafe and counterproductive work behaviors. This study examines the association between stress-related work conditions of Bus Rapid Transport (BRT) drivers and risky driving behaviors; and examines whether fatigue is a mechanism that mediates the association between the two.

METHOD

A sample of 524 male Bus Rapid Transit (BRT) operators were drawn from four transport companies in Bogotá, Colombia. The participants answered a survey which included an adapted version of the Driver Behavior Questionnaire (DBQ) for BRT operators, as well as the Effort-Reward Imbalance and Job Content Questionnaires, the Subjective Fatigue subscale of the Checklist Individual Strength (CIS) and the Need for Recovery after Work Scale (NFR).

RESULTS

Utilizing Structural Equation Models (SEM) it was found that risky driving behaviors in BRT operators could be predicted through job strain, effort-reward imbalance and social support at work. It was also found that fatigue and need for recovery fully mediate the associations between job strain and risky driving, and between social support and risky driving, but not the association between effort/reward imbalance (ERI) and risky driving.

CONCLUSIONS

The results of this study suggest that a) stress related working conditions (Job Strain, Social Support and ERI) are relevant predictors of risky driving in BRT operators, and b) that fatigue is the mechanism which links another kind of stress related to working conditions (job strain and low social support) with risky driving. The mechanism by which ERI increases risky driving in BRT operators remains unexplained.

PRACTICAL APPLICATIONS

This research suggests that in addition to the individual centered stress-reduction occupational programs, fatigue management interventions aimed to changing some working conditions may reduce risky driving behaviors and promote safety in the professional drivers' jobs and on the road.

Effects and mediators of psychosocial work characteristics on somatic symptoms six years later: Prospective findings from the Mannheim Industrial Cohort Studies (MICS)

OBJECTIVE

Ample evidence documented the adverse health effects of work stressors, and recent research has increasingly focused on somatic symptoms which are very common and costly. Prospective evidence is however sparse and yielded mixed findings. Furthermore, there is reason to assume that depression and anxiety might mediate the effects of adverse psychosocial work conditions on somatic symptoms. This study aimed to investigate longitudinal effects of work stressors on somatic symptoms and the potential mediation by anxiety and/or depression.

METHODS

Six year follow-up data from 352 individuals - free of potentially stress-related chronic disease - were utilized. Somatic symptoms were assessed by 19 items of an established list of complaints at baseline and follow-up. The effort-reward-imbalance (ERI) model measured adverse psychosocial work conditions and over-commitment (OC). Linear regressions adjusted for socio-demographics, social status, lifestyle, and baseline symptoms estimated the effects of the ERI ratio, effort, reward, OC, and the ERI ratio×OC interaction on somatic symptoms six years later. Furthermore, single and multiple mediation by anxiety and/or depression was investigated.

RESULTS

There was a strong longitudinal effect of the ERI ratio, as well as of its subcomponents, and OC on somatic symptoms (all Bs≥|0.49|; p-values ≤0.004). Moreover, the ERI ratio×OC interaction was significant (p-value=0.047). Multiple mediation analyses revealed especially anxiety to mediate the effect of work stressors on somatic symptoms (Sobel test=0.007).

CONCLUSION

Adverse psychosocial work conditions seem to longitudinally affect somatic symptoms, potentially moderated by OC, and mediated by anxiety.

The effect of effort-reward imbalance on the health of childcare workers in Hamburg: a longitudinal study

Background

The prevalence of effort-reward imbalance (ERI) among qualified childcare workers in Germany is currently estimated at around 65%. High rates of burnout and musculoskeletal symptoms (MS) have also been reported for this group. Previous longitudinal studies show inconsistent results with regard to the association between ERI and MS. As yet, no longitudinal studies have been conducted to investigate the association between ERI and burnout or MS in childcare workers. This study aims to investigate the extent to which a relationship between ERI and MS or burnout can be observed in childcare workers in Germany on a longitudinal basis.

Methods

In 2014 childcare workers (N = 199, response rate: 57%) of a provider of facilities for children and youth in Hamburg were asked about stress and health effects in the workplace. Follow-up was completed one year later (N = 106, follow-up rate: 53%) For the baseline assessment, ERI was determined as the primary influencing factor. Data on MS was recorded using the Nordic questionnaire, and burnout using the personal burnout scale of the Copenhagen Burnout Inventory (CBI). The statistical analysis was carried out using multivariate linear and logistic regression.

Results

At baseline ERI was present in 65% of the sample population. The mean burnout score at the time of follow-up was 53.7 (SD: 20.7); the prevalence of MS was between 19% and 62%. ERI was identified as a statistically significant factor for MS, after adjusting especially for physical stress (lower back: OR 4.2; 95% CI: 1.14 to 15.50, neck: OR 4.3; 95% CI: 1.25 to 15.0, total MS: OR 4.0; 95% CI: 1.20 to 13.49). With regard to burnout, a relative increase of 10% in the ERI ratio score increased the burnout score by 1.1 points (p = 0.034).

Conclusions

ERI was revealed to be a major factor in relation to MS and burnout in childcare workers. Based on this observation worksite interventions on the individual and organizational level should be introduced in order to prevent ERI.

Electronic supplementary material

The online version of this article (doi:10.1186/s12995-017-0163-8) contains supplementary material, which is available to authorized users.

Career satisfaction and work stressors in psychiatrists and psychiatry trainees in Australia and New Zealand

OBJECTIVE

To assess the level of career satisfaction and factors associated with work stress in members of the Royal Australian and New Zealand College of Psychiatrists (RANZCP).

METHODS

In 2014 an online survey was distributed to members of the RANZCP (including psychiatrists and psychiatry trainees).

RESULTS

A total of 1051 members responded to the survey. Almost 85% of respondents indicated that they were satisfied with the work they were doing at the current stage of their career. 'Too much work to do in too little time' emerged as a key stressor and was ranked as the number one stressor in last 12 months by over one third of respondents. Where applicable, examinations, prospect of revalidation and training hurdles were all noted to be moderately/extremely stressful by over 50% of respondents.

CONCLUSIONS

The majority of psychiatrists and trainees appear to be satisfied with their current work. However, there are many factors creating increased work stress and affecting welfare. The role of the college in protecting the welfare of its members should be further considered.

Associations of Occupational Stressors, Perceived Organizational Support, and Psychological Capital with Work Engagement among Chinese Female Nurses

This study aimed to explore the associations of occupational stressors (extrinsic effort, reward, and overcommitment), perceived organizational support (POS), and psychological capital (PsyCap) and its components (self-efficacy, hope, resilience, and optimism) with work engagement and the mediating roles of PsyCap and its components among Chinese female nurses within the framework of the job demands-resources (JD-R) model. A cross-sectional sample (1,330) completed the Utrecht Work Engagement Scale, Effort-Reward Imbalance Scale, Survey of POS, and PsyCap Questionnaire, and effective respondents were 1,016 (76.4%). Hierarchical regression analysis and Preacher and Hayes' asymptotic and resampling strategies were used. Extrinsic effort was negatively associated with vigor, dedication, and absorption, while POS, PsyCap, and hope were positively associated with them. Reward and overcommitment were positively associated with dedication and absorption. Optimism was positively associated with vigor and dedication. Optimism mediated the associations of extrinsic effort, reward, and POS with vigor and dedication. PsyCap and hope mediated the associations of POS with vigor, dedication, and absorption. There is a low level of work engagement among Chinese female nurses. Extrinsic effort could reduce work engagement, while reward, overcommitment, POS, PsyCap, hope, and optimism could enhance work engagement. Hospital managers should develop the PsyCap of female nurses through controlling occupational stressors and establishing supportive organizational climate to enhance their work engagement.

A systematic review and meta-analysis of the effort-reward imbalance model of workplace stress with indicators of immune function

OBJECTIVE

Despite considerable research into associations between the effort reward imbalance (ERI) model and various health outcomes over the past 20years, the underlying mechanisms responsible for the association remain unclear. Recently, ERI investigations have examined associations with immune sub-systems (e.g., leukocytes, cytokines and immunoglobulins). Synthesis of the amalgamated research evidence will aid clarity to this field of enquiry. We conducted a meta-analysis and reviewed the associations of ERI and over-commitment (OC) in the workplace with immunity.

METHOD

Electronic databases were searched with the phrase 'effort reward imbalance' which initially yielded 319 studies leading to 57 full text studies being screened. Seven studies that met inclusion criteria were combined using mixed and random effects models.

RESULTS

Greater ERI was associated with lower immunity (r=-0.09, CI -0.14, -0.05, p<0.001). Sub-group analyses revealed the effect with mucosal immunity was stronger (r=-0.33, CI -0.47 to -0.18) than trends between both cytokine (r=-0.04, CI -0.07, -0.01) and leukocyte sub-groups (r=-0.02 CI -0.04, 0.01) respectively (k=7, N=9952). Over-commitment was also associated with lower immunity (r=-0.05, CI -0.09, 0.01, p=0.014); subgroup (leukocytes, cytokines, mucosal immunity) associations, however, were homogenous (Q=1.83, df=2, p=0.400, k=6, N=2358).

CONCLUSIONS

Greater ERI and OC were both associated with lower immunity. The association between mucosal immunity and ERI was stronger than the cytokine and leukocyte sub-groups. OC moderated the relationship between ERI and immunity.

Determinants of seafarers' fatigue: a systematic review and quality assessment

PURPOSE

Fatigue jeopardizes seafarer's health and safety. Thus, knowledge on determinants of fatigue is of great importance to facilitate its prevention. However, a systematic analysis and quality assessment of all empirical evidence specifically for fatigue are still lacking. The aim of the present article was therefore to systematically detect, analyze and assess the quality of this evidence.

METHODS

Systematic searches in ten databases were performed. Searches considered articles published in scholarly journals from 1980 to April 15, 2016. Nineteen out of 98 eligible studies were included in the review. The main reason for exclusion was fatigue not being the outcome variable.

RESULTS

Most evidence was available for work time-related factors suggesting that working nights was most fatiguing, that fatigue levels were higher toward the end of watch or shift, and that the 6-h on-6-h off watch system was the most fatiguing. Specific work demands and particularly the psychosocial work environment have received little attention, but preliminary evidence suggests that stress may be an important factor. A majority of 12 studies were evaluated as potentially having a high risk of bias.

CONCLUSIONS

Realistic countermeasures ought to be established, e.g., in terms of shared or split night shifts. As internal as well as external validity of many study findings was limited, the range of factors investigated was insufficient and few studies investigated more complex interactions between different factors, knowledge derived from studies of high methodological quality investigating different factors, including psychosocial work environments, are needed to support future preventive programs.

Anxiety, Stress-Related Factors, and Blood Pressure in Young Adults

Hypertension (HT) is a long-term medical condition characterized by persistently elevated blood pressure (BP) in the arterial vessels. Although HT initially is an asymptomatic condition, it chronically evolves into a major risk factor for cardiovascular, cerebrovascular, and renal diseases that, in turn, represent crucial causes of morbidity and mortality in industrialized countries. HT is a complex disorder that is estimated to affect more than a quarter of the world's adult population. It is classified on the basis of both its pathophysiology (primary and secondary HT) and on the resting BP values (elevated systolic, diastolic, and pulse pressure). It originates from a complicated interaction of genes and several environmental risk factors including aging, smoking, lack of exercise, overweight and obesity, elevated salt intake, stress, depression, and anxiety. Anxiety and depressive disorders are the most commonly diagnosed mental disorders, affecting millions of people each year and impairing every aspect of everyday life, both of them characterized by affective, cognitive, psychomotor, and neurovegetative symptoms. Moreover, work-related stress has been considered as an important risk factor for HT and cardiovascular diseases (CVDs). Although different authors have investigated and suggested possible relations between HT, stress, anxiety, and depression during the last decades, a full understanding of the underlying pathophysiological mechanisms has not been satisfactorily achieved, especially in young adults. The aim of this study was to investigate the impact of anxiety and work-related stress in the development of HT amongst young health care profession students and the possible related consequences of early CVDs.