Interaction of Helicobacter pylori Infection with Waterpipe Tobacco Smoking in the Development of Stomach Cancer in Vietnamese Men.

Abstract

This study aims to examine the joint effect of H. pylori infection and tobacco smoking on the development of stomach cancer among Vietnamese men. A total of 80 stomach cancer cases and 146 controls were recruited in a case-control study conducted in a general hospital. Information on sociodemographic, anthropometric characteristics, tobacco smoking, and the dietary pattern was obtained based on a semi-quantitative food frequency and demographic lifestyle questionnaire; and venous anti-H. pylori IgG antibodies were tested by ELISA. Unconditional logistic regression analysis with adjustment for potential confounding was performed to estimate the association between target exposures and stomach cancer. An increase in antibody level was related to an elevated odds of stomach cancer (Fifth versus bottom quintile, OR=3.07; 95%CI: 1.16, 8.12; p for trend = 0.032). Compared to participants who were negative with both H. pylori infection and tobacco smoking (either cigarette or waterpipe tobacco), individuals exposed to both these factors showed significantly greater odds of stomach cancer (OR=3.58. (95%CI: 1.32, 9.76, p=0.013). A similar combined impact of H. pylori infection and tobacco smoking was found in individuals who smoked a cigarette (excluded exclusive waterpipe tobacco smokers, ORs = 3.17; 95%CI: 1.13, 8.94, p=0.029) or waterpipe tobacco (excluded exclusive cigarette smokers; OR= 3.96, 95%CI: 1.28, 12.26, p=0.017). The present study suggests an interaction between H. pylori infection and tobacco smoking, even waterpipe tobacco, to induce stomach cancer.