title: Helicobacter pylori infection is associated with reduced prevalence of colonic diverticular disease.
abstract: BACKGROUND
  Colonic diverticular disease is a common disorder with increasing incidence in Western societies. The intestinal microbiome may be among etiological factors. Helicobacter pylori may protect against some intestinal diseases, and incidence of H. pylori is decreasing in Western societies. Thus, we aimed to determine whether H. pylori is associated to decreased prevalence of registered colonic diverticular disease.
  
  
  METHODS
  In a historical cohort study, patients were enrolled from primary health care centers after urea breath test for H. pylori and then followed for a median of 6 years. The patient's diagnostic codes and country of birth were acquired from nationwide Danish administrative registries. We used logistic regression to compare prevalence and Cox regression to compare incidence of diverticular disease between H. pylori-positive and H. pylori-negative patients, adjusting for confounding variables.
  
  
  RESULTS
  Patients infected with H. pylori had lower prevalence of colonic diverticular disease (0.87% vs 1.14%, OR=0.62, 95% CI: 0.50-0.78). This phenomenon was observed whether we studied all registered diagnoses or only cases registered as primary diagnoses at discharge. After urea breath test, we observed no statistical difference in incidence rates of diverticular disease.
  
  
  CONCLUSIONS
  H. pylori is associated with reduced prevalence of colonic diverticular disease. The inverse association was absent after the urea breath test. Thus, we speculate that H. pylori may provide protection from colonic diverticular disease. Alternatively, H. pylori is a marker for other factors affecting disease development.
authors.affiliation: Department of Hepatology and Gastroenterology, Aarhus University Hospital, Aarhus C, Denmark.
authors.forename: Lars Erik
authors.identifier: http://orcid.org/0000-0002-9101-1076
authors.initials: LE
authors.lastname: Bartels
authors.affiliation: Department of Hepatology and Gastroenterology, Aarhus University Hospital, Aarhus C, Denmark.|Department of Clinical Epidemiology, Aarhus University Hospital, Aarhus N, Denmark.
authors.forename: Peter
authors.initials: P
authors.lastname: Jepsen
authors.affiliation: Department of Surgery, Aarhus University Hospital, Aarhus C, Denmark.
authors.forename: Anders
authors.initials: A
authors.lastname: Tøttrup
authors.affiliation: Department of Hepatology and Gastroenterology, Aarhus University Hospital, Aarhus C, Denmark.
authors.forename: Hendrik
authors.initials: H
authors.lastname: Vilstrup
authors.affiliation: Department of Hepatology and Gastroenterology, Aarhus University Hospital, Aarhus C, Denmark.
authors.forename: Jens Frederik
authors.initials: JF
authors.lastname: Dahlerup
mesh_terms: D000328:Adult; D015331:Cohort Studies; D003718:Denmark / Q000453:epidemiology; D004239:Diverticulitis, Colonic / Q000453:epidemiology*; D005260:Female; D016481:Helicobacter Infections / Q000150:complications*; D006801:Humans; D015994:Incidence; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D015995:Prevalence
keywords: H. pylori eradication; Helicobacter pylori 13C-urea breath test; cohort study; diverticular disease; epidemiology