Work-related stress and cortisol levels: is there an association? Results of an observational study

OBJECTIVE: Chronic exposure to work-related stress (WRS) stimulates the hypothalamic-pituitary-adrenal (HPA) axis to increase glucocorticoid secretion, including cortisol, and these hormones can be measured both in serum and urine. The Health Safety Executive Toolkit (HSE) questionnaire is used to assess WRS risk objectively. The scope of our study is to investigate whether serum or urinary cortisol levels could be used as alternative objective indicators of WRS, specifically in those subjects who are chronically exposed to it. PATIENTS AND METHODS: 130 patients (75 males and 55 females, mean age 47.7 ± 11.3 years) were evaluated at a specialized Centre for Secondary Hypertension, where both their serum (8 AM) and 24-hours urinary cortisol were measured and they were asked to complete two questionnaires: one questionnaire to collect data about their socio-demographic and job characteristics, and the HSE questionnaire to evaluate WRS. RESULTS: Multiple linear regression analysis showed an association of urinary cortisol with several variables: tobacco smoke (β = 69.6; p = 0.003); female gender (β = -37.3; p = 0.041); exposure to physical risks (β = 51.8; p = 0.032); control score (β = -22.7; p = 0.039); role score (β= 39.3; p = 0.020). Age was the only variable associated with serum cortisol levels (β = -3.6; p = 0.042). CONCLUSIONS: Urinary cortisol levels, but not serum levels, are associated with variables linked to WRS (score control and role) and to socio-demographic variables, namely gender and tobacco smoke. Thus, urinary cortisol can be considered a useful and non-invasive biological indicator to quantify WRS.