Abstract
BACKGROUND: Helicobacter pylori (Hp) and its virulence factor Cytotoxin-associated gene A (CagA) have been linked to myocardial infarction (MI), but the mechanisms are unknown. This study aims to test if Hp infection and CagA are associated with pre-specified inflammatory and vascular biomarkers in patients with MI and to explore whether a broader biomarker panel can predict infection. Furthermore, it aims to investigate the association of Hp infection and biomarkers with major adverse cardiovascular events (MACE) and mortality. MATERIALS AND METHODS: Hp, CagA serology, and 175 cardiovascular biomarkers were analyzed in 1061 patients with MI admitted between 2008 and 2014. Associations between Hp and seven pre-selected biomarkers were evaluated. Exploratory analyses included all biomarkers using machine-learning models to predict Hp-status. Hp-status and the top predictors were analyzed for associations with outcomes using Cox regression. RESULTS: Median age was 65 years; 78% were male. Hp and CagA seroprevalence were 45% and 19%, respectively. Patients with Hp had elevated CRP (β = 0.26, 95% CI 0.01-0.51). Predictive performance of Hp-status was moderate (AUC 0.63-0.68). Exploratory analysis identified higher levels of C-C motif chemokine ligand 20 (CCL20) and immunoglobulin heavy constant gamma-3 (IGHG3), and lower levels of TNF-related apoptosis-inducing ligand (TRAIL) in patients with Hp-positivity. Elevated CCL20 and reduced TRAIL, but not Hp, were associated with MACE and all-cause mortality. CONCLUSIONS: Hp may contribute to an inflammatory response in patients with MI, indicated by higher CRP and inflammatory/immune-modulatory biomarkers emerging as its top predictors. Although Hp was not associated with adverse outcomes after MI, its predictive inflammatory biomarkers were associated with MACE and mortality. TRIAL REGISTRATION: The study was not registered as a clinical trial, as it was an observational study.