The direct modulating role of individual stress factors on changes in psoriasis severity and itch in 67 psoriasis patients (mean age 52.3 years) was investigated. The Psoriasis Area and Severity Index (PASI) and Impact of Chronic Skin Disease on Daily Life (ISDL) were used to assess disease severity and itch, respectively. Daily stressors were assessed by the Everyday Problem Checklist and cognitive factors by the Pain Coping Inventory. Patients were followed up for 6 months. Cognitive and behavioral patterns of worrying and scratching were independently related to an increase 1 month later in the PASI and itch scores, when patients experienced a high level of daily stressors. Stressors also interacted with ...