A forward-facilitating influence of cortisol on catecholamines assessed during the work of garbage collectors

Objectives In this study, the hypothesis was tested of whether part of the hypothalamic-pituitary-adrenal system can have a facilitating influence on mean adrenomedullary reactivity during a workday. Methods Data of a field study on 115 male garbage collectors were used for this purpose. Catecholamines and cortisol were assessed by urinary sampling during a workday and during a day off. The within-subjects baseline levels of the catecholamines, personal factors, physical work load, and work char acteristics were controlled for in the analyses. Results The results showed that there is reason to assume a "forward-facili tating influence" between the aforementioned systems. The morning cortisol excretion rate explained a reasonable amount of the mean catecholamine excr etion rates during a workday. The morning cortisol level explained more var iance in the adrenaline than in the noradrenaline values, and for both cate cholamines the influence of cortisol was more pronounced than the influence of psychosocial stress factors like autonomy and job demands. Conclusions The morning level of cortisol proved to be a more powerful pred ictor of the reactivity of adrenaline than that of noradrenaline during wor k. The association between the pituitary adrenocortical system and the adre nomedullary system could therefore be a "forward-facilitating influence". i t is recommended that future research should focus on cortisol as the predi ctor of neuroendocrine reactivity and on determining whether this predictiv e power is expandable to work-induced health complaints.