Seminested Polymerase Chain Reaction (PCR) for Detecting Helicobacter pylori DNA in Carotid Atheromas

Association between Helicobacter pylori infection and carotid atherosclerosis in Chinese adults

Background and aims

The role of Helicobacter pylori (H. pylori) infection in carotid atherosclerosis remains inconsistent and sometimes controversial. We aimed to determine whether H. pylori infection is associated with carotid atherosclerotic plaques in a large number of Chinese adults.

Methods

We recruited 108,210 Chinese adults who participated in a standard medical screening with both carotid ultrasonic examination and ¹³C-urea breath test for H.pylori infection from two Chinese cohorts. A total of 93,915 adults were included in the analysis after excluding participants with cardiovascular disease (CVD) and carotid plaques at baseline. Hazard ratio (HR) for developing carotid plaques by H. pylori infection was analyzed using the Cox proportional hazard model, with sociodemographic and clinical factors adjusted. Findings across cohorts were pooled by meta-analyses.

Results

11,208 (13.13%) participants occurred carotid plaques at a median follow-up of 20 months in the MN cohort, while 1279 (14.95%) participants occurred carotid plaques at a median follow-up of 24 months in the MJ cohort. Compare with participants without H. pylori infection, participants with H. pylori infection were more likely to occur carotid plaques. After adjusting for age, sex, annual personal income, body mass index, blood pressure, blood glucose, triglycerides, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, high-sensitivity C-reactive protein, and estimated glomerular filtration rate, the HR was 1.04 (95%CI: 1.01-1.08). After further adjusting for education level, marital status, smoking status, alcohol drinking status, physical activity, and family history of CVD, the HR changed minimally. Additional sensitivity analyses confirmed the robustness of the results. Significant interactions of age, sex, blood pressure, blood glucose, or chronic inflammation were not observed in this research.

Conclusions

H. pylori infection was associated with carotid plaque onset in a large number of Chinese adults without previous CVD. These data suggested that the prevention of H. pylori infection may reduce the burden of carotid atherosclerosis.

Extragastric manifestations of Helicobacter pylori infection -- other Helicobacters

Today there is evidence that Helicobacter pylori has a critical role in different extragastric diseases. The discovery of a number of other novel Helicobacter species has stimulated the research in different extragastric diseases, in which an infectious hypothesis is plausible. Enterohepatic Helicobacter species have been hypothesized to play a role in different disorders, including hepatocellular carcinoma, gallstones formation and cholangiocellular carcinoma, as well as enteric diseases and inflammatory bowel diseases. Concerning the extragastric manifestations of H. pylori infection, idiopathic thrombocytopenic purpura, and sideropenic anemia represent, based on the current data, the diseases in which the pathogenic link appears to be strongest. There is also an increasing evidence for a possible association of H. pylori with cardiovascular disease.