Abstract
OBJECTIVE: To look for the presence of the more virulent strains of Helicobacter pylori (H pylori) in men who developed ischaemic heart disease over a 10 year period and in controls. DESIGN: The Caerphilly prospective heart disease study recruited 2512 men aged 45-59 years during 1979-83. Western blot analysis or enzyme linked immunosorbent assay (ELISA) was performed on serum taken from those who subsequently died of ischaemic heart disease, or developed non-fatal myocardial infarction, to determine H pylori and Cag A status. Similar information was available on age matched controls. RESULTS: During the first decade of the study, 312 men died of ischaemic heart disease or developed non-fatal myocardial infarction. Serum was available from 172 of these (55%). There was no evidence of an association between Cag A seropositivity and incident ischaemic heart disease or ischaemic heart disease mortality, either before or after adjustment for potential confounders (adjusted odds ratios 1.18 (95% confidence interval (CI) 0.76 to 1.85) and 1.13 (95% CI 0.61 to 2.07), respectively). Further, the odds ratios for ischaemic heart disease incidence and ischaemic heart disease mortality by H pylori seropositivity did not appear to depend on the presence or absence of Cag A strains (p = 0.76 and 0.77, respectively). CONCLUSIONS: In this cohort of middle aged men, followed over a 10 year period, there is little evidence of an association between Cag A seropositivity and either incident ischaemic heart disease or ischaemic heart disease mortality.