title: Infection with virulent strains of Helicobacter pylori is not associated with ischaemic heart disease: evidence from a population-based case-control study of myocardial infarction.
abstract: BACKGROUND
  Although the majority of evidence does not support association between Helicobacter pylori infection and ischaemic heart disease, the nature of this relationship may differ when virulence of the infecting strains are examined.
  
  
  RESULTS
  The prevalence of IgG antibody evidence of infection with CagA positive stains of H. pylori was investigated in stored plasma samples from 259 cases of myocardial infarction (aged 25-70 years, 74 males) and 259 population based controls from the same area in Northern Ireland. Two-hundred and seventy (52.1%) subjects were seropositive for anti-CagA IgG. CagA seropositivity was more common in cases than in controls: 56.4 vs 47.9%, odds ratio for seropositivity in cases (95% CI) 1.41 (1.00, 1.99). Substantial attenuation of this relationship occurred on adjustment for age, sex, number of siblings, smoking and measures of socio-economic status: odds ratio (95% CI) 1.16 (0.79, 1.70). A similar pattern was seen for seropositivity for all H. pylori strains.
  
  
  CONCLUSIONS
  Infection with the more virulent strains of H. pylori, as with all strains, is not associated with myocardial infarction.
authors.affiliation: Department of Epidemiology and Public Health, The Queen's University of Belfast, Mulhouse Building, Grosvenor Road, Belfast, UK. l.murray@qub.ac.uk
authors.forename: L J
authors.initials: LJ
authors.lastname: Murray
authors.forename: K B
authors.initials: KB
authors.lastname: Bamford
authors.forename: F
authors.initials: F
authors.lastname: Kee
authors.forename: D
authors.initials: D
authors.lastname: McMaster
authors.forename: F
authors.initials: F
authors.lastname: Cambien
authors.forename: J
authors.initials: J
authors.lastname: Dallongeville
authors.forename: A
authors.initials: A
authors.lastname: Evans
mesh_terms: D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D015897:Comorbidity; D016001:Confidence Intervals; D005260:Female; D005602:France / Q000453:epidemiology; D016481:Helicobacter Infections / Q000175:diagnosis / Q000453:epidemiology*; D016480:Helicobacter pylori / Q000472:pathogenicity*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000175:diagnosis / Q000453:epidemiology*; D017202:Myocardial Ischemia / Q000175:diagnosis / Q000453:epidemiology; D016017:Odds Ratio; D011159:Population Surveillance; D015995:Prevalence; D012307:Risk Factors; D012680:Sensitivity and Specificity; D012698:Serologic Tests; D006113:United Kingdom / Q000453:epidemiology