Synergistic Effect of Hyperglycemia and Helicobacterpylori Infection Status on Colorectal Adenoma Risk.

Context Both Helicobacter pylori and type 2 diabetes mellitus are possible risk factors for colon adenoma. Objective The purpose of this study was to assess the interaction between H. pylori and hyperglycemia status on the risk of colon adenoma. Design, Setting, and Participants This was a cross-sectional, retrospective study conducted at the MacKay Memorial Hospital, Taiwan. The study included 3943 subjects aged >40 years undergoing bidirectional gastrointestinal endoscopy on the same day between July 2006 and June 2015. All subjects had a gastric biopsy specimen tested for H. pylori. Main Outcome Measure Colon adenoma with and without H. pylori infection at different hemoglobin A1c (HbA1c) levels. Results The prevalence of colorectal adenomas in patients who were H. pylori-positive and H. pylori-negative was 37.3% and 27.29%, respectively. Multivariate logistic regression analysis identified male sex, age, body mass index, H. pylori infection, and HbA1c ≥6.5% as independent risk factors for adenoma; use of hypoglycemic agents decreased this risk. The prevalence of adenoma was increased with elevated HbA1c levels regardless of H. pylori status. The odds ratio (OR) for adenoma was 1.44 (95% confidence interval [CI], 1.20 to 1.73) if H. pylori was present or 1.68 (95% CI, 1.05 to 2.70) in patients who were H. pylori-negative but had HbA1c ≥7.0%. If both conditions were present, the OR was 4.79 (95% CI, 2.92 to 7.84). A 1% increase in HbA1c was associated with an increased prevalence of adenoma by 42.4% in H. pylori-positive subjects. Conclusions The combination of H. pylori infection and elevated HbA1c is associated with an increased risk of colon adenoma.