title: Helicobacter pylori infection: seroprevalence and predictors among healthy individuals in Al Madinah, Saudi Arabia.
abstract: BACKGROUND
  Helicobacter pylori infection is one of the most common chronic bacterial infections among humans worldwide. However, there is no information on the epidemiology of H. pylori infection in Al Madinah, Saudi Arabia.
  
  
  OBJECTIVE
  This study was conducted to determine the seroprevalence of H. pylori in asymptomatic healthy individuals and the possible relationship between H. pylori infection and sociodemographic, lifestyle, and environmental factors in this region.
  
  
  METHODS
  A hospital-based cross-sectional study was conducted on a consecutive sample of asymptomatic healthy individuals. A pilot-tested interview format was used as the research tool. Venous blood was collected from individuals and sera were separated. The enzyme-linked immunosorbent assay was used to determine H. pylori IgG antibody levels in all serum samples.
  
  
  RESULTS
  A total of 456 samples were collected. H. pylori antibodies were found in 129 (28.3%) individuals. Seroprevalence of 16.9% was found in individuals younger than 20 years of age, which gradually increased with age and reached 36.8% by the age of 50. After controlling for the confounding factors, significant independent predictors of seropositive state were: rural residence [odds ratio (OR)=2.5, 95% confidence interval (CI)=1.3, 4.7], crowded housing (OR=1.6, 95% CI=1.1, 2.6), low socioeconomic status (OR=3.3, 95% CI=1.6, 8.8), using tanks for drinking water supply (OR=2.2, 95% CI=1.2, 7.4), active smoking (OR=5.6, 95% CI=3.2, 9.8), alcohol drinking (OR=2.3, 95% CI=1.5, 6.2), eating raw vegetables (OR=3.2, 95% CI=1.4, 7.1), eating spicy food (OR=2.1, 95% CI=1.3, 3.5), and presence of asthmatic/atopic symptoms (OR=2.5, 95% CI=1.3, 5.9). No associations were found between infection and age, gender, source of sewage disposal, eating fruits, or family history of upper gastrointestinal symptoms.
  
  
  CONCLUSIONS
  Infection with H. pylori is declining among healthy individuals of Al Madinah, Saudi Arabia. Infection is acquired at an early age and reaches up to 36.9% as age advances. The risk of H. pylori seropositivity was related to socioeconomic, lifestyle, and environmental factors. A nationwide epidemiological study is warranted to determine the seroprevalence of H. pylori in Saudi Arabia.
authors.affiliation: aDepartment of Community Medicine, Faculty of Medicine, Alexandria University, Alexandria, Egypt bDepartment of Family and Community Medicine, Medical College, Taibah University, Al Madinah, Saudi Arabia.
authors.forename: Manal I
authors.initials: MI
authors.lastname: Hanafi
authors.forename: Aida M
authors.initials: AM
authors.lastname: Mohamed
mesh_terms: D003430:Cross-Sectional Studies; D016481:Helicobacter Infections / Q000097:blood; D016480:Helicobacter pylori / Q000276:immunology; D006801:Humans; D012529:Saudi Arabia / Q000453:epidemiology; D016036:Seroepidemiologic Studies