Psoriasis is a polygenetic hereditary multifactorial disease which may be influenced by a number of environmental factors. To date only a few studies experimentally investigated the influence of stress on psoriasis. One problem of these studies is that it remains unclear whether the experimental findings are relevant for the entire group of patients, or whether there are subgroups who are particularly susceptible to stress. Therefore our main objective is to examine whether experimental stressors can identify subgroups of patients who are particularly susceptible to stress and if these differ in immunological parameters.
Method: The Trier Social Stress Test (TSST) was used as stressor. The severity was recorded both objectively using the PASI (Psoriasis Area and Severity Index) as well as subjectively by the patient. Somatic parameters for which stress reactivity is known but no direct relationship to psoriasis is assumed were selected and exploratively examined within the present study (salivary cortisol). The second set of parameters for which the stress reactivity was unclear included variables which are linked to the pathophysiology and/or the severity of psoriasis. In addition to salivary cortisol, eosinophils, ICAM-3, and sIL-2R were determined in serum. 38 psoriasis patients and 38 control subjects were examined (21 male and 17 female participants within each group).
Results: The PASI correlated very inconsistently with the subjective severity parameters. The relationships between severity and blood parameters tested showed a systematic relationship for eosinophils only. The TSST is suitable for eliciting stress in psoriasis patients. In one subgroup, there was an increase in skin affliction, while skin affliction in the second group remained constant or decreased. A classification into stress-reactive or non-reactive patients cannot, however, be supported by the immunological parameters tested.