ObjectiveThe objective of this survey was to study the association between Helicobacter pylori infection and the severity of coronary atherosclerosis.MethodsThe study population consisted of 961 consecutive patients (711 males and 250 females) who underwent coronary angiography for suspected or known coronary atherosclerosis. The patients' body mass index, blood pressure, the blood lipid, blood glucose, leukocyte count (109/L), neutrophil count (109/L), and Helicobacter pylori-specific IgG antibodies were performed. Coronary angiograms were scored according to vessel score and Gensini's score.ResultsA significant association between H. pylori infection and coronary atherosclerosis as well as its severity was not find in this cross section study (p = 0.858). And, the level distribution of vessel score (p = 0.906) and Gensini's score (p = 0.905) were similar in the seropositivity group and seronegativity group of Helicobacter pylori infection. However, the level of fasting high-density lipoprotein cholesterol (mmol/L) (p = 0.013) was significantly lower in the seropositivity group than that in the seronegativity group of Helicobacter pylori infection.ConclusionsIn conclusion, in the present study, a significantly correlation between Helicobacter pylori seropositivity and angiographically evaluated severity of atherosclerosis was not find. And, the present study showed a good correlation between Helicobacter pylori infection and decreased HDL cholesterol. However, the exact mechanisms need further study.