Higher overcommitment to work is associated with higher plasma cortisol but not ACTH responses in the combined dexamethasone/CRH test in apparently healthy men and women

SummaryBackgroundOvercommitment (OC) is a pattern of excessive striving that has been associated with alterations in the hypothalamus–pituitary–adrenal (HPA) system. To investigate whether overcommitment is associated with alterations in HPA system function we measured cortisol and adrenocorticotropin (ACTH) release in response to the combined dexamethasone/CRH test.MethodsWe recruited 92 men and 108 women of a wide range of OC scores including the minimum (6) and maximum (24) of possible OC scores (mean ± SEM: 13.25 ± .27). We repeatedly measured plasma cortisol and ACTH levels in the combined dexamethasone/CRH test after injection of 100 μl CRH preceded by administration of 1.5 mg dexamethasone the night before. Moreover, we assessed depressive symptoms (Beck Depression Inventory, BDI) and work stress (effort–reward–imbalance, ERI).ResultsIndependent of age and gender, higher OC was associated with higher repeated cortisol (interaction time-by-OC: p = .014, f = .15) but not ACTH (p = .22) secretion in the combined dexamethasone/CRH test. Similarly, higher cortisol (β = .16, p = .029, R2 = .02) but not ACTH (p = .47) increase following CRH injection was predicted by higher OC. Depressive symptoms (BDI score) and work stress scores (effort–reward-ratio) did not relate to neuroendocrine responses to the dexamethasone/CRH test. Controlling for depressive symptoms and work stress scores in addition to age and gender did not change results. OC was not associated with ACTH or cortisol pre-test levels.DiscussionWhereas OC was not associated with alterations in negative feedback sensitivity after dexamethasone administration, our findings indicate that with increasing OC scores, a higher reactivity of the adrenal cortex together with a normal reactivity of the pituitary is observed following subsequent stimulation by CRH injection.