Bile Acid Sequestrant Use and Gastric Cancer: A National Retrospective Cohort Analysis

INTRODUCTION:Bile acids have been implicated in gastric carcinogenesis. We hypothesized that bile acid sequestrant medication (BAM) use is associated with a lower gastric cancer (GC) incidence.METHODS:We assembled a cohort of veterans receiving longitudinal care within the Veterans Health Administration between 2000 and 2020 who completed testing for Helicobacter pylori. The index date was the date of completed H. pylori testing. The primary exposure was the number of filled BAM prescription(s) in the 5 years before the index date. The primary outcome was incident GC, stratified by anatomic subsite. Follow-up began at the index date and ended at the earliest of GC, death, after 2 years of follow-up, or the study end (May 31, 2020). We used Kaplan-Meier curves to visualize differences in GC incidence by exposure group and multivariable Cox proportional hazards models to estimate the association between BAM exposure and anatomic site-specific GC.RESULTS:Among 417,239 individuals (89% male, mean age 54 years, 63% non-Hispanic White), 4,916 (1.2%) filled at least one BAM prescription, 2,623 of whom filled >= 4. Compared with unexposed individuals, those with >= 4 BAM fills before entry had a lower incidence (adjusted hazard ratio 0.71; 95% confidence interval, 0.37-1.36) of GC, but confidence intervals were wide. Results were consistent irrespective of GC anatomic site.DISCUSSION:BAMs may have a protective effect against both cardia and noncardia GC. Further research and external validation are needed to confirm these findings.