Job strain as a risk factor for clinical depression: systematic review and meta-analysis with additional individual participant data

Abstract

BackgroundAdverse psychosocial working environments characterized by job strain (the combination of high demands and low control at work) are associated with an increased risk of depressive symptoms among employees, but evidence on clinically diagnosed depression is scarce. We examined job strain as a risk factor for clinical depression.MethodWe identified published cohort studies from a systematic literature search in PubMed and PsycNET and obtained 14 cohort studies with unpublished individual-level data from the Individual-Participant-Data Meta-analysis in Working Populations (IPD-Work) Consortium. Summary estimates of the association were obtained using random-effects models. Individual-level data analyses were based on a pre-published study protocol.ResultsWe included six published studies with a total of 27 461 individuals and 914 incident cases of clinical depression. From unpublished datasets we included 120 221 individuals and 982 first episodes of hospital-treated clinical depression. Job strain was associated with an increased risk of clinical depression in both published [relative risk (RR) = 1.77, 95% confidence interval (CI) 1.47–2.13] and unpublished datasets (RR = 1.27, 95% CI 1.04–1.55). Further individual participant analyses showed a similar association across sociodemographic subgroups and after excluding individuals with baseline somatic disease. The association was unchanged when excluding individuals with baseline depressive symptoms (RR = 1.25, 95% CI 0.94–1.65), but attenuated on adjustment for a continuous depressive symptoms score (RR = 1.03, 95% CI 0.81–1.32).ConclusionsJob strain may precipitate clinical depression among employees. Future intervention studies should test whether job strain is a modifiable risk factor for depression.

Effort–reward imbalance at work and risk of depressive disorders. A systematic review and meta-analysis of prospective cohort studies

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Do resources buffer the prospective association of psychosocial work stress with depression? Longitudinal evidence from ageing workers

“…This disorder is linked to a reduction in the quality of life, premature retirement, and more years with disability (3). With regard to its causes, depression is known to be a multifactorial disorder with biological, environmental, and psychological factors involved in its development (4)(5)(6)(7)(8), including psychosocial work stressors (9)(10)(11). To date, most studies have investigated the association between psychosocial work stressors and depression measuring work stressors according to the models of effort-reward imbalance (ERI) and job strain.…”

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The challenge of tied autonomy for traditional work stress models

“…CHD, depression) (e.g. Kivimäki, Nyberg, & Batty, 2012;Madsen et al, 2017). Researchers who are sympathetic to Karasek's model have pointed out that these meta-analyses have many methodological problems.…”