Association of early-stage psoriasis with smoking and male alcohol consumption - Evidence from an Italian case-control study

Objective: To analyze the association of psoriasis with smoking habits and alcohol consumption before first diagnosis by a dermatologist. Design: A multicenter case-control study. Interviews were conducted by trai ned medical investigators using a structured questionnaire. Setting: Outpatient services of 10 general and 10 teaching hospitals in nor thern and southern Italy. Subjects: Patients with a first diagnosis of psoriasis made by a dermatolog ist and a history of skin manifestations of no longer than 2 years after th e reported disease onset. Patients with new diagnoses of skin diseases othe r than psoriasis were selected as control subjects. A total of 404 case pat ients (median age, 35 years) and 616 controls (median age, 36 years) were i ncluded in the analysis. Results: The risk for psoriasis was higher in ex-smokers and in current smo kers than in patients who never smoked. The relation with smoking was stron ger and more consistent among women than men. In men, a significant associa tion was restricted to the ex-smoker status. Smoking was strongly associate d with pustular lesions (29 patients) with an adjusted odds ratio of 10.5 ( 95% confidence interval, 3.3-33.5) for those smoking more than 15 cigarette s per day. No significant overall association with alcohol consumption was documented after controlling for smoking habits. However, the risk seemed t o vary according to sex, with a moderate association being documented in me n. Conclusions: Cigarette smoking and, in men, alcohol consumption are associa ted with psoriasis. There is a strong association between smoking and pustu lar lesions.