S144 Association of Helicobacter pylori Infection With Hepatobiliary and Pancreatic Malignancies: A Nationwide Analysis

Introduction: H. pylori is known for its role in gastric cancer, but emerging evidence suggests a possible link to hepatobiliary and pancreatic malignancies. Most of these studies originate from high-prevalence regions, and large national studies, especially on rarer malignancies like ampullary cancer, remain limited. This study examines the potential association between H. pylori and Hepatobiliary and Pancreatic malignancies. Methods: We conducted a retrospective cohort study using the National Inpatient Sample (2019 to 2022). ICD-10 codes identified adults with H. pylori infection and ampullary, pancreatic, bile duct, gallbladder, and liver cancer, excluding metastatic and unspecified biliary malignancies. Multivariable logistic regression estimated adjusted odds ratios (aORs), controlling for demographics, comorbidities, smoking, family history, socioeconomic status, and hospital factors. We performed propensity score matching with post-matching regression to assess residual confounding. A sub-analysis among H. pylori-positive patients evaluated risk factors for malignancies. Results: Among 114 million adult discharges, H. pylori infection (n ≈ 108,485) was associated with significantly increased odds for having a co-diagnosis of the studied malignancies. This association remains significant after matching (19,945 with H. pylori, 50,976 matched controls). Among patients with H. pylori infection, Asian and Pacific Islander race (aOR 1.70, P = 0.005), family history of GI malignancy (aOR 1.91, P = 0.020), and older age (aOR 1.02/year, P < 0.001) significantly increased the odds of co-diagnosis with studied malignancies; while sex, Black or Hispanic race, and smoking did not. Conclusion: In this analysis of hospitalized patients, H. pylori infection was significantly associated with hepatobiliary and pancreatic malignancies, most strongly with ampullary cancer. This association should be interpreted cautiously due to potential confounding by indication, as many of our H. pylori-positive patients possibly underwent testing for gastrointestinal symptoms. This limitation is common in administrative data studies lacking clinical details. Despite these limitations, our findings, supported by high statistical power, suggest a potential association and highlight the need for longitudinal studies to clarify H. pylori’s role. Future research should use time-to-event methods and examine whether eradication reduces cancer risk, particularly in high-risk groups.