Work related stress and severe depressive symptoms:

Introduction
The potential depressogenic effect of work related stress has rarely been studied prospectively in nationally representative samples. Because doctors exhibit high levels of depressive symptoms and constitute a relatively homogeneous group as regards work related stress, this occupational group is ideal for investigating the influence of different job stress factors on future severe depressive symptoms.

Methods
From 1994 to 2008, graduating medical students (N = 631) at all 4 Norwegian universities participated in a longitudinal survey. They were followed up 1 (T1), 10 (T2), and 15 (T3) years after their graduating term. Severe depressive symptoms, were measured by the General Health Questionnaire-28 (Severe Depression subscale) (sumscore T2 and T3). Work stress was measured by an established job stress questionnaire including four dimensions; emotional pressure; time pressure; fear of complaints and criticism, and work-home interference (Cooper/Tyssen).

Results
The mean severe depressive symptom scores were at T2 and T3 respectively were 8.2 (SD = 2.8) and 7.8 (2.2), with no gender differences in these levels. Time pressure (Beta = 0.14, p < 0.05, CI = 0.04-1.19) and emotional pressure (Beta = 0.23, p < 0.01, CI = 0.43-1.60) univariately predicted severe depressive symptoms. In a multivariate regression model, controlling for age and gender, time pressure (Beta = 0.22, p < 0.01, 0.39-1.52) and emotional pressure (Beta = 0.14, p < 0.05, 0.02-1.10) both remained significant predictors of severe depressive symptoms.

Discussion
This is the first study to demonstrate that daily experiences of time or emotional pressure in the work place predicts severe depressive symptoms as long as 9 years later. These findings should draw attention to work environment not only of doctors, but also to other occupations characterized by considerable time and emotional pressure. Interventions aimed at reducing employees’ experience of such stresses should be discussed.