title: The prevalence of Helicobacter pylori is decreasing in Iranian patients.
abstract: OBJECTIVE
  The objective of this study was to evaluate the time trend of Helicobacter pylori (H. pylori) prevalence and presence of intestinal Metaplasia over the period of seven years among gastritis Iranian patients.
  
  
  BACKGROUND
  H. pylori is the major causal factor in chronic gastritis. Its acquisition leads to a chronic, usually lifelong, inflammation of the gastric mucosa, which may gradually progress to atrophy with intestinal metaplasia in a significant proportion of infected individuals.
  
  
  METHODS
  H. pylori and intestinal Metaplasia data among 14,860 consecutive gastritis patients, who referred to the gastrointestinal department of Tehran's Taleghani Hospital in Iran from 2008 to 2014, was examined by sex and age group. The patients were divided into six age groups (16-30, 30-40, 40-50, 50-60 and >70). The chi-square test was used to compare the qualitative variables.
  
  
  RESULTS
  The overall prevalence rate among patient with H. pylori infection was 83.5% (12406/14860) and 11,394 (84.1%) of them were related to the gastritis. The prevalence rate of H. pylori among patient with severe gastritis was significantly higher (P<0.05) compared to mild and moderate gastritis. In addition, the prevalence of H. pylori decreased with age and has been declined in recent years. The presence of intestinal metaplasia increased with age (P<0.05).
  
  
  CONCLUSIONS
  The results of this study showed that the prevalence of H. pylori infection in Iranian population has been declined in recent years; nevertheless it seems to be highly prevalent in Iran. We also find a significant positive relationship between H. pylori infection and gastritis. There is no association between sex and infection, however in contrast with the most studies its prevalence decreased with age.
authors.affiliation: Gastroenterology and Liver Disease Research center, Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Science, Tehran, Iran.
authors.forename: Sara
authors.initials: S
authors.lastname: Ashtari
authors.affiliation: Gastroenterology and Liver Disease Research center, Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Science, Tehran, Iran.
authors.forename: Mohamad Amin
authors.initials: MA
authors.lastname: Pourhoseingholi
authors.affiliation: Gastroenterology and Liver Disease Research center, Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Science, Tehran, Iran.
authors.forename: Mahsa
authors.initials: M
authors.lastname: Molaei
authors.affiliation: Department of Biostatistics, Shahid Beheshti University of Medical Science, Tehran, Iran.
authors.forename: Hajar
authors.initials: H
authors.lastname: Taslimi
authors.affiliation: Gastroenterology and Liver Disease Research center, Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Science, Tehran, Iran.
authors.forename: Mohammad Reza
authors.initials: MR
authors.lastname: Zali
keywords: Gastritis; Intestinal metaplasia; Iranian population; Prevalence of H. pylori