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 t he development of atherosclerosis. Chronic infections may activate an infla mmatory response in the walls of blood vessels. Objective To investigate the possibility of there being an association betw een infection with Helicobacter pylori (H. pylori) and coronary heart disea se. Methods We examined 100 consecutive patients documented to have recently su ffered acute myocardial infarction and 100 control subjects from the same g eographical area for whom there was no evidence of coronary heart disease, carefully matched both for age and sex. Blood samples were tested for the p resence of immunoglobulin G antibodies against H. pylori with a serological test. Results In comparison with controls, patients were more commonly smokers (2 6 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 ser opositivity for H. pylori and having previously suffered acute myocardial i nfarction (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 i ncluding 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 a nd having previously suffered acute myocardial infarction found in this stu dy provides further support for the hypothesis that there is a causal assoc iation between chronic infection with H. pylori and the development of coro nary heart disease. Coron Artery Dis 11:523-526 (C) 2000 Lippincott William s & Wilkins.