[The relationship between psychogenic excoriation and psychiatric disorders: a comparative study]

Psychogenic excoriation (PE), characterized by excessive scratching or picking of the skin, is not yet recognized as a symptom of a distinct DSM-IV disorder. It is a chronic disorder with a high rate of psychiatric comorbidity. The purpose of this study was to compare patients diagnosed with PE and another group of psychodermatosis patients in terms of comorbid psychiatric disorders.

Thirty-one consecutive subjects were recruited from an outpatient dermatology clinic. The control group was composed of 31 patients with a dermatological disease other than PE. Subjects were interviewed using the Structured Clinical Interview for DSM-III-R, Beck Depression Inventory (BDI), Hamilton Anxiety Rating Scale (HARS) and the Yale-Brown Obsession and Compulsion Scale (YBOCS). Subjects also completed a semi-structured questionnaire for socio-demographic data and clinical features.

Current major depressive syndrome was the most common psychiatric disorder in the PE group. There was a statistically significant difference between the two groups in terms of current major depressive syndrome (PE group 58.1%, control group 6.5%, p<0.01). Some 45.2% of the PE group was diagnosed with obsessive compulsive disorder (OCD) while the proportion was only 3.7% in the control group. This difference was also statistically significant (p<0.01). The PE group scored significantly higher in the BDI, HARS and the YBOCS.

The results of this study point to a close relationship between PE and depression and OCD.