Re: "changes in perceived job strain and the risk of major depression: results from a population-based longitudinal study"

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.

Changes in psychosocial work environment and depressive symptoms: a prospective study in junior physicians

BACKGROUND

We examined the impact of changes in the psychosocial work environment on depressive symptoms in a sample of junior physicians, a high risk group for stress and mental disorders.

METHODS

This is a three-wave prospective study in 417 junior physicians during their residency in German hospitals. The psychosocial work environment was measured by the Effort-Reward Imbalance (ERI) Questionnaire at Waves 1 and 2, and the depressive symptoms were assessed with the State-Trait Depression Scales at all three waves. Multivariate linear regression was applied for prospective associations between ERI across Waves 1 and 2, and baseline-adjusted depressive symptoms at Wave 3.

RESULTS

Compared with the ERI scores at Wave 1, at Wave 2, and mean scores between the two waves, the baseline-adjusted ERI change scores between the two waves showed slightly better statistical power, predicting depressive symptoms at Wave 3 (β = 0.78, 95% CI = 0.38-1.18 for increased ERI per SD, β = 0.64, 95% CI = 0.22-1.06 for increased effort per SD, β = -0.65, 95% CI = -1.06 to -0.24 for increased reward per SD, and β = 0.68, 95% CI = 0.27-1.09 for increased overcommitment per SD).

CONCLUSIONS

Negative changes in the psychosocial work environment, specifically increased ERI, are associated with depressive symptoms in German junior physicians. Reducing the non-reciprocity of working life, particularly improving reward at work, may have beneficial effects on prevention of mental health problems in the hospital workplace.