It has been documented that cortisol release in response to acute stressors is reduced in patients with atopic dermatitis, allergic rhinitis, and other atopic diseases compared to that in healthy subjects. We aimed to test the hypothesis that atopic patients exert reduced salivary cortisol awakening response (CAR) in comparison with healthy subjects. The hypothesis was tested on a stressful and a relax day selected subjectively. Moreover, we evaluated the impact of trait anxiety. The sample consisted of 60 subjects, out of which 28 were patients with atopy and 32 healthy volunteers of both sexes. Saliva samples were collected in the morning to evaluate CAR as well as in the early afternoon and evening to look at cortisol concentrations during the rest of the day. The results showed reduced CAR in atopic patients compared to that in healthy subjects. This effect was modulated by sex with a significant difference observed in males. While CAR was reduced, atopic patients had unchanged cortisol concentrations throughout the day. The evening cortisol was even higher in atopic patients. If the subjects were stratified according to the trait anxiety, no significant differences in CAR between high and low anxiety were observed. No differences in cortisol variables including CAR were observed between the stressful and relax day. In conclusion, this study presents evidence on reduced CAR suggesting an insufficient HPA axis reactivity in atopy. Furthermore, the data in atopic patients demonstrate that reduced HPA axis reactivity does not necessarily mean lower cortisol concentrations throughout the day. This might be of relevance to immune system function and the course of the disease.
Keywords: Atopy; Salivary cortisol; Stress; Trait anxiety.