RESPONSE OF THE PITUITARY-ADRENAL AXIS IN TERMS OF TYPE-A BEHAVIOR, HOSTILITY AND VITAL EXHAUSTION IN HEALTHY MIDDLE-AGED MEN

Pituitary-adrenal axis was studied in terms of Type A behaviour, hosti lity and vital exhaustion among 69 healthy middle-aged men. The result s showed that psychological factors could explain a significant propor tion of the biologically manipulated responses of HPA axis, bur they w orked in different ways. Type A behaviour was related to a high level of mean basal ACTH and a low level of cortisol response to ACTH stimul ation after dexamethasone suppression; hostility was related to a high level of mean basal cortisol and a high cortisol in cortisol/ACTH rat io, while vital exhaustion was characterized by a low level of mean ba sal ACTH and a decreased ACTH in relation to cortisol. The adrenocorti cal patterns, i.e, a high ACTH-low cortisol; a high cortisol; and a lo w ACTH-low mean basal cortisol, as related to Type A behaviour, hostil ity and exhaustion, respectively, are in line with the traditional phy siological stress model and suggest that different adrenocortical resp onses might be able to identify different mental stress processes. Sen se of control has been suggested to be a key concept for psychological understanding of this finding.