Lack of association of Helicobacter pylori infection with coronary artery disease and frequency of acute myocardial infarction or death

We investigated the association between Helicobacter pylori (H. pylori) infection and coronary artery disease (CAD) in 2 study populations: (1) a cross-sectional study to determine risk of having CAD, and (2) a longitudinal study to determine risk of acute myocardial infarction (AMI) or death over a mean follow-up period of 3 years in patients with angiographically documented CAD. Blood samples were tested for serum immunoglobulin G antibodies to H. pylori and C-reactive protein (CRP) levels. Study 1: Of 391 patients (62% men, mean age 57 years), 41% had antibodies to H. pylori. CAD prevalence was 70% in H. pylori seropositive patients and 59% in seronegative patients (p = 0.03). Elevated CRP levels (>0.5 mg/dl) were significantly higher in patients with than without CAD (p = 0.02). By univariate analysis, CAD prevalence significantly increased stepwise depending on H. pylori seropositivity and elevated CRP levels (p = 0.008). Significance was lost after adjustment for traditional risk factors. Further analyses revealed that age was the critical confounder. Study 2: Of 929 patients (77% men, mean age 65 years), 56% had antibodies to H. pylori. By univariate analysis, the incidence of AMI or death was 22% in H. pylori seropositive patients and 18% in seronegative patients (p = 0.1). The adjusted hazard ratio of AMI or death for H. pylori seropositivity was 1.12 (95% confidence interval 0.81 to 1.54). Our data suggest that prior infection with H. pylori is not a major factor determining either risk of CAD, AMI, or death in patients with CAD.