Associations of Helicobacter Pylori with Anemia: A Bidirectional Two-Sample Mendelian Randomization Study

Background Observational studies have reported a correlation between Helicobacter pylori infection and an increased incidence of anemia, iron deficiency anemia (IDA), and vitamin B12 deficiency anemia. However, the fundamental cause remains elusive. This study aimed to ascertain the causal relationship between H. pylori infection and anemia. Method Using data from genome-wide association studies (GWAS), we executed a bidirectional Mendelian randomization (MR) study utilizing two-sample GWAS. The principal analytical method was the inverse variance weighted (IVW) method. We employed a conservative Bonferroni-corrected threshold (p < 2.38 × 10 − 3 ). Sensitivity analyses were implemented with Cochran’s Q test and MR-Egger regression. Results Genetically predicted H. pylori infection, anti- H. pylori CagA, VacA, and IgG seropositivity was not causally associated with anemia, IDA, or vitamin B12 deficiency anemia (p > 2.38 × 10 − 3 ). Furthermore, reverse MR analysis did not reveal evidence for a causal effect of anemia on H. pylori infection (p > 0.05). Conclusions Utilizing genetic data, MR analysis demonstrated the absence of evidence for a causal association between the seroprevalence of H. pylori infection and anemia. Further research is needed to elucidate the relationship between H. pylori infection and anemia.