title: Colonic mucosal lesions associated with low-dose aspirin: a case control study.
abstract: OBJECTIVE
  Low-dose aspirin (LDA) is widely used because it reduces the risk of vascular events in patients with atherosclerosis. Recently, there has been a substantial increase in prescriptions for LDA. We analyzed the risk of colonic mucosal lesions associated with the long-term use of LDA.
  
  
  METHODS
  Among Japanese patients who underwent a colonoscopy between January 2004 and December 2006, 199 colitis cases and 5764 non-colitis controls were identified after excluding 749 patients based on study criteria. The history of LDA use was compared between the cases and controls and the multivariate (age-, sex- and underlying diseases-) adjusted odds ratio (OR) was estimated using a multiple logistic regression model.
  
  
  RESULTS
  The adjusted OR for colonic mucosal lesions associated with LDA use versus non-use was 1.45 [95% confidence interval (CI), 0.87-2.42; p = 0.152]. In terms of gender differences, the OR for LDA-induced colitis in females was significantly increased at 2.55 (95% CI, 1.31-4.94; p = 0.006) but was not significantly increased in males at 0.70 (95% CI, 0.34-1.45; p = 0.334).
  
  
  CONCLUSIONS
  In females, LDA increased the risk of colonic mucosal lesions, suggesting that LDA may contribute to the pathogenesis of colonic ulceration or colitis. Therefore, it is essential that prescribing physicians be aware of the risk of LDA-induced colonic lesions.
authors.affiliation: Department of Gastroenterology, Juntendo University School of Medicine, Tokyo, Japan. tomoyosi@juntendo.ac.jp
authors.forename: Tomoyoshi
authors.initials: T
authors.lastname: Shibuya
authors.forename: Toshifumi
authors.initials: T
authors.lastname: Ohkusa
authors.forename: Tetsuji
authors.initials: T
authors.lastname: Yokoyama
authors.forename: Kenshi
authors.initials: K
authors.lastname: Matsumoto
authors.forename: Kazuko
authors.initials: K
authors.lastname: Beppu
authors.forename: Naoto
authors.initials: N
authors.lastname: Sakamoto
authors.forename: Taro
authors.initials: T
authors.lastname: Osada
authors.forename: Akihito
authors.initials: A
authors.lastname: Nagahara
authors.forename: Michiro
authors.initials: M
authors.lastname: Otaka
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Ogihara
authors.forename: Sumio
authors.initials: S
authors.lastname: Watanabe
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001241:Aspirin / Q000008:administration & dosage / Q000009:adverse effects*; D003092:Colitis / Q000139:chemically induced* / Q000473:pathology*; D003113:Colonoscopy; D005260:Female; D006801:Humans; D007413:Intestinal Mucosa / Q000473:pathology*; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D012189:Retrospective Studies; D012737:Sex Factors; D013997:Time Factors; D055815:Young Adult
chemical_list: D001241:Aspirin