Do positive psychosocial work factors protect against two-year incidence of long-term sickness absence among employees with and those without depressive symptoms? A prospective study

Objective: This study sought to examine the influence of protective work factors on long-term sickness absence among employees reporting different levels of depressive symptoms in a representative sample of the Danish workforce. Methods: Questionnaire data was collected from a random sample of members of the Danish workforce aged 18-64 using data from two surveys with baselines in 2000 and 2005. From the year 2000 baseline questionnaires from 5510 employees (2790 male and 2720 female) were included and from the 2005 baseline, 8393 employees (3931 male and 4462 female). Baseline data were collected on depressive symptoms, leadership, colleague support and decision latitude. Information on twoyear incidence of sickness absence was derived from an official register. Results: Stratified analyses on depressive symptoms scores (none, moderate and severe) indicate that quality of leadership was associated with reduced sickness absence to a somewhat stronger degree for those with moderate depressive symptoms (adjusted HR 0.88, 95% CI 0.78 to 0.98) than for those without depressive symptoms, and high decision latitude was associated with reduced sickness absence to a somewhat larger degree for those without depressive symptoms (adjusted HR 0.91, 95% CI 0.85 to 0.97) than for those with depressive symptoms. However, quality of leadership and decision latitude did not interact significantly with depressive symptom status. Conclusions: Quality of leadership may protect against long-term sick leave to a certain degree in those with moderate depressive symptoms. Possible interactions between psychosocial working conditions and depression status should be investigated in larger populations.