Increase Risk of Helicobacter pylori-Induced Gastric Cancer in Patients With Iron Deficiency Anemia: A Population Based Study

Introduction: Iron deficiency anemia (IDA) is a common hematological manifestation in patients with gastric cancers (GC). Over the years, studies have shown strong associations between systemic iron overload and development of cancer, but only a few studies have shown a relationship between IDA and cancer development. Data from comprehensive studies have shown that patients with IDA respond poorly to GC therapy. Other articles have reported some evidence of accelerated Helicobacter pylori induced carcinogenesis in patients with IDA. This begs the question whether patients with Helicobacter pylori infection who have had iron deficiency anemia are at higher risk of developing gastric cancer compared to the ones without IDA, prompting our decision to carry out this study. Methods: A Multicenter and research platform database of more than 360 hospitals from 26 different healthcare systems across the United States from 1999 to September 2022 was utilized to construct this study. We included patients aged 18 years and above who have received a diagnosis of Helicobacter pylori infection. Multivariate analysis using backward stepwise logistic regression was performed to calculate the risk of developing gastric cancer. Male gender, smoking history, alcoholism, iron deficiency anemia, Asian and African American ethnicities were included in the logistic regression. A 2-sided P value < 0.05 was considered as statistically significant. Results: 79,445,329 individuals were screened in the database and 84,900 were selected in the final analysis. The baseline characteristics of patients with gastric cancer is seen in Table 1. Using a stepwise multivariate regression analysis, risk of gastric cancer in patients who have had a diagnosis of Helicobacter pylori infection was increased in males (OR: 3.47), Asian (OR: 4.14) and African American (OR: 2.08) ethnicities, patient with IDA (OR: 2.84), smoking history (OR: 2.04), and alcoholism (OR: 2.42) (Figure 1). Conclusion: Our study illustrates that patients with Helicobacter pylori infection who had iron deficiency anemia are at higher risk of developing gastric cancer compared to the ones without IDA. Based on our understanding, this stems from weakened functioning capability of cells involved in tumor immune-surveillance. Clinicians should be aware of this association and are encouraged to remain vigilant for need for endoscopy and Iron supplementation with IDA in patients with Helicobacter pylori infection.Figure 1.: Forest plot for risk of developing NASH versus control Abbreviations: H. pylori infection, Helicobacter pylori infection; T2DM, type 2 diabetes mellitus. Table 1. - Baseline characteristics of patients with gastric cancer and control Parameters Gastric cancer (%) No Gastric cancer (%) African American 130 (32.50) 16,610 (19.65) Asian 20 (5.00) 2,930 (3.46) IDA 150 (37.50) 11,850 (14.02) Smoker 120 (30.00) 15,740 (18.62) Alcohol 40 (10.00) 5,120 (6.05) Obesity 80 (20.00) 24,440 (28.92) Male 230 (57.50) 31,830 (37.66) Total 400 84,500 Abbreviation: IDA, iron deficiency anemia.