Relationship Between Helicobacter pylori Infection and Serum Interleukin-18 in Patients with Carotid Atherosclerosis

Background Helicobacter pylori (H.pylori) infection stimulates the production of proinflammatory cytokines associated with the development of atherosclerosis. Levels of circulating interleukin-18 (IL-18) have been positively correlated with carotid intima-media thickness (IMT) and coronary plaque area and have identified IL-18 levels as important predictors of coronary events and cardiovascular mortality. This study aimed to examine the relationship between serum IL-18 and H.pylori-IgG antibody as a sign of H.pylori infection in patients with carotid atherosclerosis. Methods The carotid IMT, traditional atherosclerotic risk factors, levels of serum H.pylori-IgG and IL-18 were measured in 573 health checkup examinees. Results Serum IL-18 and H.pylori-IgG levels were significantly increased in subjects with increased IMT in comparison with those with normal IMT. In subjects with increased IMT, serum H.pylori-IgG was positively correlated with serum IL-18 (r=.402, p=.002), and the association was independent of traditional atherosclerotic risk factors (=0.310, p<.001). Conclusions In health checkup examinees with increased IMT, serum IL-18 and H.pylori-IgG were independently correlated and were significantly higher than in subjects with normal IMT.