Effect of Helicobacter pylori Eradication Therapy on the Incidence of Noncardia Gastric Adenocarcinoma in a Large Diverse Population in the United States

BACKGROUND & AIMS: High-quality data regarding the effect of Helicobacter pylori eradication on the risk of noncardia gastric adenocarcinoma (NCGA) remain limited in the United States. We investigated the incidence of NCGA after H pylori eradication therapy in a large, community-based US population. METHODS: We performed a retrospective cohort study of Kaiser Perma-nente Northern California members who underwent testing and/ or treatment for H pylori between 1997 and 2015 and were followed through December 31, 2018. The risk of NCGA was evaluated using the Fine-Gray subdistribution hazard model and standardized incidence ratios. RESULTS: Among 716,567 in-dividuals with a history of H pylori testing and/or treatment, the adjusted subdistribution hazard ratios and 95% confidence in-tervals of NCGA for H pylori-positive/untreated and H pylori- positive/treated individuals were 6.07 (4.20-8.76) and 2.68 (1.86-3.86), respectively, compared with H pylori-negative in-dividuals. When compared directly with H pylori-positive/un-treated individuals, subdistribution hazard ratios for NCGA in H pylori-positive/treated were 0.95 (0.47-1.92) at <8 years and 0.37 (0.14-0.97) & GE;8 years of follow-up. Compared with the Kaiser Permanente Northern California general population, standardized incidence ratios (95% confidence interval) of NCGA steadily decreased after H pylori treatment: 2.00 (1.79-2.24) & GE;1 year, 1.01 (0.85-1.19) & GE;4 years, 0.68 (0.54-0.85) & GE;7 years, and 0.51 (0.38-0.68) & GE;10 years. CONCLUSION: In a large, diverse, community-based population, H pylori eradication therapy was associated with a significantly reduced incidence of NCGA after 8 years compared with no treatment. The risk among treated in-dividuals became lower than the general population after 7 to 10 years of follow-up. The findings support the potential for sub-stantial gastric cancer prevention in the United States through H pylori eradication.

Automated summary

This large-scale retrospective cohort study in the United States investigated the incidence of noncardia gastric adenocarcinoma (NCGA) after Helicobacter pylori eradication therapy. The findings showed a significantly reduced risk of NCGA after 8 years of treatment compared to no treatment. This study highlights the potential for substantial gastric cancer prevention through H pylori eradication. Evaluation: 8 out of 10.