Greater than normal prevalence of seropositivity for Helicobacter pylori among patients who have suffered myocardial infarction

Background There is evidence to suggest that inflammation plays a role in the development of atherosclerosis. Chronic infections may activate an inflammatory response in the walls of blood vessels. Objective To investigate the possibility of there being an association between infection with Helicobacter pylori (H. pylori) and coronary heart disease. Methods We examined 100 consecutive patients documented to have recently suffered acute myocardial infarction and 100 control subjects from the same geographical area for whom there was no evidence of coronary heart disease, carefully matched both for age and sex. Blood samples were tested for the presence of immunoglobulin G antibodies against H. pylori with a serological test. Results In comparison with controls, patients were more commonly smokers (26 versus 12%, P < 0.05) and had more commonly been treated for hypertension (37 versus 20%, P < 0.01). There was a significant association between seropositivity for H. pylori and having previously suffered acute myocardial infarction (68 versus 53%, odds ratio 1.36 with 95% confidence interval 1.02-1.82, P=0.034). These findings remained valid in a multivariate analysis including possible confounding factors (age, sex, smoking and hypertension; odds ratio 1.35 with 95% confidence interval 1.01-1.83, P=0.046). Conclusions The positive association between seropositivity for H. pylori and having previously suffered acute myocardial infarction found in this study provides further support for the hypothesis that there is a causal association between chronic infection with H. pylori and the development of coronary heart disease. Coron Artery Dis 11:523-526 (C) 2000 Lippincott Williams & Wilkins.