Published online Apr 26, 2015. doi: 10.4330/wjc.v7.i4.187
Peer-review started: October 24, 2014
First decision: December 26, 2014
Revised: January 16, 2015
Accepted: February 4, 2015
Article in press: February 9, 2015
Published online: April 26, 2015
Processing time: 178 Days and 21 Hours
In this review, we discussed the findings and concepts underlying the potential role of Helicobacter pylori (H. pylori) infections in the initiation, development or persistence of atherosclerosis and coronary heart disease (CHD). This Gram-negative bacterium was described by Marshall and Warren in 1984. The majority of infected subjects carries and transmits H. pylori with no symptoms; however, in some individuals these bacteria may cause peptic ulcers, and even gastric cancers. The widespread prevalence of H. pylori infections and the fact that frequently they remain asymptomatic may suggest that, similarly to intestinal microflora, H. pylori may deliver antigens that stimulate not only local, but also systemic inflammatory response. Recently, possible association between H. pylori infection and extragastric disorders has been suggested. Knowledge on the etiology of atherosclerosis together with current findings in the area of H. pylori infections constitute the background for the newly proposed hypothesis that those two processes may be related. Many research studies confirm the indirect association between the prevalence of H. pylori and the occurrence of CHD. According to majority of findings the involvement of H. pylori in this process is based on the chronic inflammation which might facilitate the CHD-related pathologies. It needs to be elucidated, if the infection initiates or just accelerates the formation of atheromatous plaque.
Core tip:Helicobacter pylori (H. pylori) is a Gram-negative spiral bacterium which colonizes gastric mucosa of nearly half of human population. A characteristic feature of H. pylori infection is an excessive inflammatory response. The majority of H. pylori infections remain asymptomatic. However, still it leads to the development of histological gastritis with the recruitment of immune cells. About 10% of infected subjects develop symptomatic gastritis, erosions or peptic ulcer. Gastric cancer is the most severe consequence of H. pylori infection. Recently, a possible association between chronic infections with H. pylori and extragastric disorders - including coronary heart disease, has been intensively investigated. Here we have revised recent studies confirming or excluding possible connections between chronic bacterial infections and the occurrence of coronary heart disease (CHD) within different populations, especially in the context of H. pylori infections. We have also presented various study approaches investigating direct and indirect interplay between H. pylori-driven consequences and CHD development to clarify already gained knowledge and suggest future directions. Considering the significance of already conducted research studies, the involvement of H. pylori infection in the process of CHD development is highly probably, however, still a lot need to be done to clarify whether this association is direct (with the involvement of H. pylori antigens and products) or indirect (with the involvement of inflammatory-related molecules accelerating/initiating CHD development).