Alcohol misuse in patients with psoriasis: identification and relationship to disease severity and psychological distress

Background Moderate to severe psoriasis is associated with increased alcohol intake and excessive mortality from alcohol-related causes. Alcohol biomarkers provide an objective measure of alcohol consumption. Carbohydrate-deficient transferrin (CDT) is the single most sensitive and specific alcohol biomarker. Objectives To assess alcohol consumption in a cohort of patients with moderate to severe psoriasis using standard alcohol screening questionnaires and biomarkers. We investigated whether there was an association between alcohol intake, anxiety, depression and disease severity. Methods Consecutive patients with chronic plaque psoriasis were recruited and completed a range of anonymized assessments. Psoriasis severity, anxiety and depression, and the impact of psoriasis on quality of life were assessed. Alcohol screening questionnaires were administered. Blood specimens were taken and γ-glutamyltransferase (γGT) and CDT were measured. Results A total of 135 patients completed the study. Using validated questionnaires, between 22% and 32% had difficulties with alcohol. Seven per cent had CDT > 1·6% indicating a heavy alcohol intake. The Alcohol Use Disorders Identification Test (AUDIT) questionnaire was superior to other validated questionnaires in detecting alcohol misuse. There were no significant associations between measures of excessive alcohol consumption and disease severity. Excessive alcohol intake as measured by the CAGE questionnaire was associated with increased depression (P = 0·001) but other measures of alcohol excess did not correlate with psychological distress. Men had significantly more difficulties with alcohol than women (P < 0·001). Conclusion Alcohol misuse is common in patients with moderate to severe psoriasis. Screening with the AUDIT questionnaire and CDT may allow the identification of patients who are misusing alcohol and allow appropriate intervention.