The Association Between Helicobacter pylori Seropositivity and Colorectal Adenoma : A Case-Control Study

Abstract

Introduction: Several studies on the association between Helicobacter pylori (H. pylori) infection and colorectal adenoma have been reported recently. But the results have been controversial. The aim of this study is to examine whether H. pylori seropositivity is associated with colorectal adenoma. Methods: Individuals who underwent screening colonoscopy were recruited. After colonoscopy, the subjects were grouped into two groups: subjects with colorectal adenoma (cases) and subjects whose colonoscopic findings were normal (controls). Individuals with hyperplastic or malignant polyp were excluded. All subjects were questioned about smoking, alcohol, weekly exercise, diabetes mellitus, hypertension, medication history and a family history of colorectal cancer. Subjects underwent various anthropometric and laboratory tests including serum IgG antibody against H. pylori. Results: Total 1,780 age and sex matched subjects were allocated in each group: 890 in case and 890 in control group. The mean age of subjects was 55.5±7.6 years and 1,358 (76.3%) were male. The H. pylori serology was positive for 1,035 (58.1%) and negative for 745 (41.9%) subjects. By univariate analysis, the prevalence of H. pylori was slightly higher in the adenoma group than in the control group, but this association was not statistically significant (OR, 1.19

95% CI, 0.98-1.44

P=0.074). Hypertension, smoking, alcohol, abdominal obesity, obesity, triglyceride and a family history of colorectal cancer were significantly higher in the adenoma group than control group. Multivariate analysis to adjust for possible confounders revealed that H. pylori infection was not a significant risk factor for colorectal adenoma (OR, 1.20

95% CI, 0.98-1.46

P=0.075). H. pylori infection was not associated with the characteristics of colorectal adenoma such as number, size, location or advanced adenoma (size> 1cm, high grade dysplasia, villous component). Conclusions: In this large-scale case-control study, the association of H. pylori seropositivity and colorectal adenoma was not statistically significant, so H. pylori infection might not be a risk factor for colorectal adenoma. Further studies are necessary for the identification of association with H. pylori infection and colorectal adenoma.