Ischaemic heart disease and Cag A strains of Helicobacter pylori in the Caerphilly heart disease study

Objective To look for the presence of the more virulent strains of Helicoba cter 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 ag ed 45-59 years during 1979-83. Western blot analysis or enzyme linked immun osorbent assay (ELISA) was performed on serum taken from those who subseque ntly died of ischaemic heart disease, or developed non-fatal myocardial inf arction, to determine H pylori and Cag A status. Similar information was av ailable on age matched controls. Results-During the first decade of the study, 312 men died of ischaemic hea rt disease or developed non-fatal myocardial infarction. Serum was availabl e from 172 of these (55%). There was no evidence of an association between Cag A seropositivity and incident ischaemic heart disease or ischaemic hear t disease mortality, either before or after adjustment for potential confou nders (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 f or ischaemic heart disease incidence and ischaemic heart disease mortality by H pylori seropositivity did not appear to depend on the presence or abse nce of Cag A strains (p = 0.76 and 0.77, respectively). Conclusions-In this cohort of middle aged men, followed over a 10 year peri od, there is little evidence of an association between Cag A seropositivity and either incident ischaemic heart disease or ischaemic heart disease mor tality.