title: Smoking habits in psoriasis: a case control study.
abstract: We have examined smoking habits in 108 patients with psoriasis, including some with palmoplantar distribution, and compared the results with matched controls from the community. There was a significant association between psoriasis, current smoking status (OR = 2.7, 95% CI 1.44-5.42, P less than 0.01) and smoking habits prior to the onset of disease (OR = 3.75, 95% CI 1.68-9.47, P less than 0.001). There was also a marked dose-response relationship; the relative risk of psoriasis in those currently smoking more than 20 cigarettes/day was significantly elevated (OR = 5.3, 95% CI 2.1-13.0, P less than 0.001). Separate analysis of patients without palmoplantar distribution of psoriasis showed a significant association with smoking prior to onset of psoriasis (OR = 3.6, 95% CI 1.5-9.8, P less than 0.001). Smoking may play a role in the aetiology of this common skin disorder.
authors.affiliation: Department of Gastroenterology, University Hospital of Wales, Cardiff, U.K.
authors.forename: C M
authors.initials: CM
authors.lastname: Mills
authors.forename: E D
authors.initials: ED
authors.lastname: Srivastava
authors.forename: I M
authors.initials: IM
authors.lastname: Harvey
authors.forename: G L
authors.initials: GL
authors.lastname: Swift
authors.forename: R G
authors.initials: RG
authors.lastname: Newcombe
authors.forename: P J
authors.initials: PJ
authors.lastname: Holt
authors.forename: J
authors.initials: J
authors.lastname: Rhodes
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011565:Psoriasis / Q000453:epidemiology / Q000209:etiology*; D012907:Smoking / Q000009:adverse effects*; D012923:Social Class