ASPO Abstracts
Smoking, Helicobacter pylori serology, and gastric cancer risk in a consortium of prospective studies from China, Japan, and Korea
Category: Molecular Epidemiology & Environment
Conference Year: 2019
Abstract Body:
Purpose: Tobacco smoking is considered as a risk factor for the development of gastriccancer (GC). We here aim to assess the association of smoking with GC risk in 1,446non-cardia GC cases and 1,796 matched controls from the Helicobacter pylori (H. pylori)Biomarker Cohort Consortium with samples from China, Japan, and Korea. Since H. pylori isthe leading causal factor for GC we address this question considering H. pylori infectionas a potential confounder or effect modifier. Methods: We applied logistic regression models stratified by study and adjusting for age,sex and BMI to calculate odds ratios (OR) and 95% confidence intervals (95% CI) for theassociation of smoking (never, former, current) with GC risk. Overall H. pylorisero-positivity as well as sero-positivity to the H. pylori GC biomarker HP0305/OMP wereapplied to the model as potential confounders. Second, the association of smoking with GCrisk was determined with stratification by overall H. pylori or HP0305/OMP sero-status toassess potential effect modification. Results: Current smoking was significantly associated with GC risk (OR: 1.21, 95% CI:1.02-1.44). Adjustment for overall H. pylori sero-positivity did not substantially alterthe overall OR (OR: 1.30, 95% CI: 1.04-1.62) but the association lost significance whenadjusting for HP0305/OMP sero-positivity (OR: 1.23, 95% CI: 0.98-1.53). Stratifying byoverall H. pylori sero-positivity revealed that current smoking only increased GC riskamong H. pylori sero-positive (OR: 1.35, 95% CI: 1.07-1.71) but not sero-negativeindividuals (OR: 0.78, 95% CI: 0.39-1.56), however, there was no significant interaction(p-value = 0.335). Stratification by the GC associated biomarker HP0305/OMPsero-positivity, in contrast, showed a significant interaction (p-value = 0.005) with asignificant 42% increased risk of GC among HP0305/OMP sero-positive current smokers (95%CI: 1.07-1.89).Conclusion: In conclusion, we confirmed previous findings that smoking is associated withan increased GC risk. However, taking into consideration the H. pylori GC biomarkerHP0305/OMP sero-status, current smoking increases GC risk only among individuals that aresimultaneously sero-positive for the leading causal factor for GC, H. pylori.
Keywords: Gastric cancer risk;smoking;Helicobacter pyloriserology