title: Psoriasis and Smoking: A Systematic Literature Review and Meta-Analysis With Qualitative Analysis of Effect of Smoking on Psoriasis Severity.
abstract: BACKGROUND
  Smoking has been associated with psoriasis prevalence and severity.
  
  
  OBJECTIVE
  To evaluate prevalence of smoking in patients with psoriasis and to examine the relationship between smoking and psoriasis severity.
  
  
  METHODS
  MEDLINE, EMBASE, and Cochrane databases (1960-2012) and conference proceedings (2010-2012) were systematically searched using keywords relevant to psoriasis and smoking. Controlled studies addressing psoriasis and smoking status were included. A meta-analysis for the relative risk of smoking in psoriasis patients was performed.
  
  
  RESULTS
  Meta-analysis identified a significant association between smoking and psoriasis with a relative risk of 1.88 (95% CI, 1.66-2.13) for smoking in patients with psoriasis versus patients without psoriasis. Eight articles of 11 with data on smoking and psoriasis severity suggested that severity increases with smoking status.
  
  
  CONCLUSIONS
  This literature review is in favor of a positive association between the prevalence of smoking and psoriasis as well as an association between smoking and severity of psoriasis.
authors.affiliation: Department of Medicine, Dermatology Service, St-Luc Hospital, Montreal, Quebec, Canada vincent.richer@umontreal.ca.
authors.forename: Vincent
authors.initials: V
authors.lastname: Richer
authors.affiliation: University of Montreal Hospital Research Center (CRCHUM), Notre-Dame Hospital, Montreal, Quebec, Canada.
authors.forename: Camille
authors.initials: C
authors.lastname: Roubille
authors.affiliation: Division of Dermatology, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Patrick
authors.initials: P
authors.lastname: Fleming
authors.affiliation: Sacré-Coeur Hospital of Montreal, University of Montreal, Montreal, Quebec, Canada.
authors.forename: Tara
authors.initials: T
authors.lastname: Starnino
authors.affiliation: Department of Dermatology and Skin Science, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Collette
authors.initials: C
authors.lastname: McCourt
authors.affiliation: Division of Rheumatology, University of Alberta, Edmonton, Alberta, Canada.
authors.forename: Alexandra
authors.initials: A
authors.lastname: McFarlane
authors.affiliation: Division of Rheumatology, Department of Medicine, Western University of Canada, London, Ontario, Canada.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Siu
authors.affiliation: Lynde Dermatology, Markham, Ontario, Canada.
authors.forename: John
authors.initials: J
authors.lastname: Kraft
authors.affiliation: Lynde Dermatology, Markham, Ontario, Canada.
authors.forename: Charles
authors.initials: C
authors.lastname: Lynde
authors.affiliation: Division of Rheumatology, Department of Medicine, Western University of Canada, London, Ontario, Canada.
authors.forename: Janet E
authors.initials: JE
authors.lastname: Pope
authors.affiliation: Division of Rheumatology, University of Alberta, Edmonton, Alberta, Canada.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Keeling
authors.affiliation: Department of Dermatology and Skin Science, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Jan
authors.initials: J
authors.lastname: Dutz
authors.affiliation: Department of Medicine, Rheumatic Disease Unit, Centre Hospitalier Universitaire de Québec (pavillon CHUL), Quebec City, Quebec, Canada.
authors.forename: Louis
authors.initials: L
authors.lastname: Bessette
authors.affiliation: Department of Medicine, Memorial University of Newfoundland, St John's, Newfoundland, Canada.
authors.forename: Wayne P
authors.initials: WP
authors.lastname: Gulliver
authors.affiliation: Department of Medicine, Rheumatic Disease Unit, Centre Hospitalier de l'Université de Montréal (CHUM) and Institut de Rhumatologie de Montréal, Montreal, Quebec, Canada.
authors.forename: Boulos
authors.initials: B
authors.lastname: Haraoui
authors.affiliation: Innovaderm Research, Montreal, Quebec, Canada.
authors.forename: Robert
authors.initials: R
authors.lastname: Bissonnette
mesh_terms: D006801:Humans; D015995:Prevalence; D011565:Psoriasis / Q000453:epidemiology* / Q000473:pathology; D012720:Severity of Illness Index; D012907:Smoking / Q000453:epidemiology*
keywords: dermatology; psoriasis