Background: Dysregulation of the hypothalamic pituitary adrenal (HPA)-axis is hypothesized to underlie stress-related psychiatric disorders such as post-traumatic stress disorder (PTSD). We aimed to explore whether trauma exposure is associated with alterations in HPA-axis functioning in the absence of lifetime psychiatric morbidity. Method: We included 39 trauma-exposed healthy male subjects (mean age = 47 years; SD = 9.2) and 24 non-exposed healthy male controls (mean age = 47.4 years; SD = 14.5). All subjects were free of lifetime psychopathology. Basal salivary cortisol levels (on two consecutive days) as well as the cortisol and adrenocorticotropic hormone (ACTH) response to the combined dexamethasone/corticotropin releasing hormone (Dex/CRH) challenge test were analyzed using general linear models (GLM) adjusted for body mass index, age and smoking status. Results: A blunted salivary cortisol awakening response was found in the exposed group compared to the non-exposed group (F(1,57) = 5.46, p = .02). Consistent with these findings, salivary diurnal cortisol was lower in the trauma-exposed versus non-exposed group (F(1,57) = 4.04, p =.05). No differences, however, were found between both groups for plasma cortisol or ACTH responses to the Dex/CRH test. Conclusion: Low basal cortisol levels were found in trauma-exposed men, suggesting that HPA-axis alterations in men are associated with trauma exposure during adulthood, also in the absence of psychopathology. (C) 2009 Elsevier Ltd. All rights reserved.