title: Predictors of failure of Helicobacter pylori eradication and predictors of ulcer recurrence: a randomized controlled trial.
abstract: OBJECTIVE
  In light of evidence that Helicobacter pylori treatment fails 5% to 20% of the time, the objective of this study was to determine predictors of unsuccessful H. pylori eradication and of duodenal ulcer recurrence.
  
  
  METHODS
  Randomized, double-blind, placebo-controlled trial.
  
  
  METHODS
  Gastroenterology services of 2 general hospitals in Montreal, Que.
  
  
  METHODS
  All patients (aged 16 to 90) with an endoscopically proven duodenal ulcer within the previous year and H. pylori infection detected on antral biopsy were asked to participate; 85 were included.
  
  
  METHODS
  Patients were randomized in double-blind fashion to 1 of 2 eradication therapies, consisting of metronidazole, bismuth subcitrate and either amoxicillin or placebo. Endoscopy was performed at follow-up every 3 months for 12 months.
  
  
  METHODS
  Demographic data, characteristics of patients and disease, previous history and family history of ulcer disease, compliance at day 10 and day 28 of therapy; in vitro metronidazole resistance of H. pylori; eradication of H. pylori (determined by endoscopic biopsy 3 months after therapy); and ulcer recurrence within 12 months after therapy.
  
  
  RESULTS
  Metronidazole resistance (odds ratio [OR] 0.11, 95% confidence interval [CI] 0.017 to 0.69) was the only independent predictor of eradication. Compliance (as defined in the study), density of organisms on culture, as well as several other factors examined, were not significant predictors. Treatment group, although a significant factor on univariate analysis, was not an independent predictor on multivariate analysis, as there were relatively good eradication rates (82% and 97% among compliant patients) in both groups. With regard to ulcer recurrence, 3 independent predictors were identified: failed H. pylori eradication (OR 86.5, 95% CI 4.2 to 1769), unemployment (OR 13.2, 95% CI 1.8 to 95) and a family history of ulcer disease (OR 12.2, 95% CI 1.2 to 128).
  
  
  CONCLUSIONS
  The best predictor of ulcer recurrence is failure of H. pylori eradication, which, in turn, depends on metronidazole resistance. Hence, treatments containing metronidazole should be avoided in populations with high rates of metronidazole resistance. A family history of ulcer disease and unemployment were also predictors of ulcer recurrence, which suggests a potential role for treatment of contacts.
authors.affiliation: Division of Gastroenterology, McGill University Health Centre, Montreal, Que. cfallone@lan1.molonc.mcgill.ca
authors.forename: C A
authors.initials: CA
authors.lastname: Fallone
authors.forename: V
authors.initials: V
authors.lastname: Loo
authors.forename: L
authors.initials: L
authors.lastname: Joseph
authors.forename: J
authors.initials: J
authors.lastname: Barkun
authors.forename: R
authors.initials: R
authors.lastname: Kostyk
authors.forename: A N
authors.initials: AN
authors.lastname: Barkun
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000658:Amoxicillin / Q000627:therapeutic use; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D000897:Anti-Ulcer Agents / Q000627:therapeutic use*; D004381:Duodenal Ulcer / Q000188:drug therapy* / Q000382:microbiology / Q000517:prevention & control; D004724:Endoscopy; D005260:Female; D005500:Follow-Up Studies; D016480:Helicobacter pylori / Q000187:drug effects*; D006801:Humans; D008297:Male; D008795:Metronidazole / Q000627:therapeutic use; D008875:Middle Aged; D009942:Organometallic Compounds / Q000627:therapeutic use; D010406:Penicillins / Q000627:therapeutic use; D011237:Predictive Value of Tests; D011792:Quebec; D012008:Recurrence; D017211:Treatment Failure
chemical_list: D000900:Anti-Bacterial Agents; D000897:Anti-Ulcer Agents; D009942:Organometallic Compounds; D010406:Penicillins; D008795:Metronidazole; D000658:Amoxicillin; C002791:bismuth tripotassium dicitrate