Background: It is widely accepted that episodes of seborrheic dermatitis are frequently induced by stress, as stated in all general reviews of the subject. However, there have been no studies to confirm this view.
Patients and methods: This prospective study was performed in two phases. An initial questionnaire collected information on patients' identity, somatic and psychiatric history and seborrheic dermatitis characteristics. Information on triggering episodes was sought by means of an open question and patients were then asked if they had experienced stress during the week or month prior to the active episode. A second questionnaire containing the same questions (except for history) was completed four months later. The two questionnaires contained psychopathological evaluation scales designed to detect symptoms of anxiety and depression among patients (HAD: Hospital Anxiety and Depression scale; Beck; STAI: State-Trait Anxiety Inventory) and determine their perceived stress (PSS: Perceived Stress Scale by Cohen and Williamson).
Results: Eighty-two patients (36 women and 46 men) were included in the study. 82% of patients presented involvement of scalp, 33% of the face, 19% of the chest and 13% of other sites (ears, skinfolds). Patients themselves identified stress as the main triggering factor, whether for episodes in general, for the first episode or for the current episode. A stressful event was in fact found in the majority of cases. The fact that stress was recognised as a triggering factor for episodes was not associated with a higher depression score (HAD or Beck) but was associated with a higher anxiety score (STAI). The psychological effects of the disease were pronounced in 11% of patients, moderate in 20%, mild in 35%, and nil in 25%, with 9% of patients stating no opinion. Patients with facial involvement were more depressed in terms of Beck Depression Index score. Two characteristics noted at inclusion were predictive for the onset of at least one further episode or persistence of an ongoing episode four months later: patients' designation of stress as the cause of the previous episode, and STAI score.
Discussion: This study confirms that seborrheic dermatitis is often preceded by a stressful event and that stress tends to suggest a poor prognosis. This is the first study to show a possible link between stressful life events and episodes of seborrheic dermatitis. It suggests the need to confirm these results through a study comparing patients with seborrheic dermatitis and subjects without the disease. It also shows that depression is more common among patients with facial involvement and that anxiety is an aggravating factor.