Helicobacter pylori Infection Is Associated With Reduced Risk of Barrett's Esophagus: An Analysis of the Barrett's and Esophageal Adenocarcinoma Consortium

OBJECTIVES: Epidemiological studies ofHelicobacter pyloriinfection and risk of Barrett's esophagus (BE) have reported conflicting results. We examined the association betweenH. pyloriinfection and BE and sought to determine whether the association is mediated by gastroesophageal reflux disease (GERD) and to identify potential effect modifiers. METHODS: We used individual level data from 1308 patients with BE (cases), 1388 population-based controls, and 1775 GERD controls in the Barrett's and Esophageal Adenocarcinoma Consortium (BEACON). We estimated study-specific odds ratios (ORs) and 95% CIs using multivariable logistic regression models and obtained summary risk estimates using a random-effects meta-analytic approach. We examined potential effect modification by waist-to-hip ratio (WHR), body mass index (BMI), and smoking status by conducting stratified analyses. RESULTS: For comparisons with population-based controls,H. pyloriinfection was inversely associated with the risk of BE (adjusted OR = 0.44, 95% CI = 0.36-0.55), with no evidence of between-study heterogeneity (I2 = 0%). A stronger inverse association betweenH. pyloriand BE was observed among individuals with the CagA-positive strain (Pfor interaction = 0.017). We found no evidence of interaction between WHR, BMI, smoking status, andH. pyloriinfection on the risk of BE. There was no association betweenH. pyloriinfection and BE for comparisons with GERD controls (OR = 0.96, 95% CI = 0.67-1.37;I2 = 48%). CONCLUSIONS: This study provides the strongest evidence yet thatH. pyloriinfection is strongly inversely associated with BE. This effect is probably mediated by a decrease in GERD in infected patients, since the protective effect disappears in patients with GERD symptoms.