OBJECTIVES: Perceived Stress is a suspected cause of many psychological and physical illnesses. However it remains to be discovered what physiological measures are involved. While it is widely known that acute stress leads to an increase in cortisol levels, the findings in prolonged stress research have not been consistent. This study explores the association between Perceived Stress and salivary cortisol levels using the largest population ever used in this field. METHOD: 4467 public employees in the PRISME cohort in 2007. 3217 of those did a similar follow up study in 2009. A 4-item Danish version of the PSS-scale was used to measure perceived stress and operationalized as the average score. Salivary cortisol samples were taken at 30 min post awakening and at 8 pm. A mean value of cortisol was calculated. In our analysis we applied logarithmic transformation to the concentrations. RESULTS: Linear regression analysis done for the association between PSS-score and salivary cortisol levels showed no significant association between the two. For cortisol mean the regression resulted in β=-0.005(Cl: -0.036-0.026) in 2007 and -0.010(Cl: -0.047-0.028) in 2009. Cortisol morning analysis resulted in β= -0.013(Cl: -0.050-0.023) in 2007 and β= -0.003(Cl: -0.048-0.042) in 2009. Cortisol evening analysis resulted in in β= -0.000(Cl: -0.042-0.042) in 2007 and β= -0.007(Cl: -0.047-0.061) in 2009. CONCLUSIONS: Overall this study does not provide any evidence that perceived stress is associated with salivary cortisol.
Occupational and Environmental Medicine, 2014, Vol 71 Suppl 1