title: Does smoking influence the risk of pouchitis following ileal pouch anal anastomosis for ulcerative colitis?
abstract: OBJECTIVE
  According to epidemiological studies, smoking habit is strongly associated with inflammatory bowel disease. Non-smokers, and especially recent ex-smokers, have an increased risk of ulcerative colitis (UC). Conversely, concerning Crohn's disease, the risk is increased among smokers. Pouchitis is the major long-term complication of restorative proctocolectomy for UC, and seems to be pathogenetically related to this condition. The aims of this study were to test the hypothesis that smoking reduces the risk of pouchitis, and to investigate whether cessation of smoking precedes the onset of the inflammation.
  
  
  METHODS
  All living patients operated on for UC with proctocolectomy and ileal pouch anal anastomosis (IPAA) between November 1982 and November 1996 at Sahlgren's University Hospital were included in the study (n=410). Data concerning smoking habits and pouchitis were obtained from questionnaires and from medical records. The correlation between smoking habits and incidence of pouchitis was statistically evaluated by means of a survival test and a multivariate analysis, i.e. a Poisson model.
  
  
  RESULTS
  In all, 327 patients (80%) completed the questionnaires. Ninety-six (29%) of these patients had had at least one episode of pouchitis. Smoking habits during follow-up did not significantly influence the risk of pouchitis (p=0.29). Nor did smoking habits before and at the time of IPAA correlate with the incidence of pouchitis. Women had a decreased risk of pouchitis, compared to men (p=0.014). There was a non-significant tendency for smoking to increase the risk, which was more pronounced in women.
  
  
  CONCLUSIONS
  Smoking does not decrease the risk of pouchitis following IPAA for UC, and in this respect the pathogenetic model of pouchitis, suggested to be a manifestation of UC, is not supported.
authors.affiliation: Department of Surgery, Colorectal Unit, Sahlgrenska University Hospital, Göteborg, Sweden.
authors.forename: Magnus
authors.initials: M
authors.lastname: Joelsson
authors.forename: Cecilia
authors.initials: C
authors.lastname: Benoni
authors.forename: Tom
authors.initials: T
authors.lastname: Oresland
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D003093:Colitis, Ulcerative / Q000601:surgery*; D039021:Colonic Pouches; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D019449:Pouchitis / Q000209:etiology*; D016737:Proctocolectomy, Restorative; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects*