Stress-induced immunomodulation is altered in patients with atopic dermatitis

Atopic dermatitis (AD) is a chronically relapsing inflammatory skin disease with main symptoms such as eczematous skin lesions and severe pruritus. Although the relevance of stress in the pathology of AD is widely accepted, the underlying biological mechanisms of stress-induced exacerbation of AD symptoms are not fully understood. The specific goal of the present study was to investigate the impact of acute psychosocial stress on atopy-relevant immune functions in AD sufferers. AD patients (n=36) and nonatopic controls (n=37) were exposed to a laboratory stressor including a free speech and mental arithmetic tasks in front of an audience ("Trier Social Stress Test," TSST). Blood samples were collected 10 min before and 1, 10 and 60 min after the stress test as well as 24 h after the experiment at identical time points under resting conditions. Analyses of leukocyte subsets indicated significantly elevated lymphocyte, monocyte, neutrophil and basophil numbers 10 min after the TSST (all p's<0.001) with no significant differences between the two groups. In contrast, eosinophil number was found to be significantly elevated only in AD sufferers, but not subjects (F(3,213)=4.8; p<0.01). Moreover, AD patients but not the control group showed increased IgE levels (F(1,71)=4.4; p<0.05) 24 h after the stress test. Exposure to the TSST resulted in elevation of interferon-gamma (IFN-gamma; F(3,207)=19.55; p<0.001) and, further, in attenuation of interleukin-4 (IL-4; F(3,207)=187.46; p<0.001) concentrations with no significant differences between both groups (all p's>0.05). The present findings suggest that stress may be associated with atopy-relevant immunological changes in AD sufferers, which may be one explanation of the common observation of stress-induced aggravation of symptomatology in this patient group.