Purpose: This study aimed to investigate the association between serum levels of cortisol and dehydroepiandrosterone sulfate (DHEA-s) and sickness absence over 2 years in Japanese male workers.
Method: A baseline survey including questions about health behavior, along with blood sampling for cortisol and DHEA-s, was conducted in 2009. In total, 429 men (mean ± SD age, 52.9 ± 8.6 years) from whom blood samples were collected at baseline were followed until December 31, 2011. The hazard ratios (HR) and 95% confidence intervals (CI) for sickness absence were calculated using a Cox proportional hazard model, adjusted for potential confounders.
Results: Among 35 workers who took sickness absences, 31 had physical illness. A high cortisol to DHEA-s ratio increased the risk of sickness absence (crude HR = 2.68, 95% CI 1.12-6.41; adjusted HR = 3.33, 95% CI 1.35-8.20). The cortisol to DHEA-s ratio was linearly associated with an increased risk of sickness absence (p for trend < .050). Single effects of cortisol and DHEA-s levels were not associated with sickness absences. This trend did not change when limited to absences resulting from physical illness.
Conclusion: Hormonal conditions related to the hypothalamus-pituitary-adrenocortical axis and adrenal function should be considered when predicting sickness absence. The cortisol to DHEA-s ratio may be more informative than single effects of cortisol and DHEA-s levels.
Keywords: Cortisol; DHEA-s; Japanese male workers; Prospective study; Sickness absence.