Absence of causative genetic association between Helicobacter pylori infection and glaucoma: a bidirectional two-sample mendelian randomization study

While clinical research has indicated a potential link between infection and the onset of glaucoma, the causality of this association remains uncertain due to the susceptibility of observational studies to confounding factors and reverse causation. A comprehensive two-sample bidirectional Mendelian randomization (MR) analysis was conducted to assess the causal connection between infection and glaucoma. Glaucoma was categorized into primary open-angle glaucoma (POAG), normal tension glaucoma (NTG), and pseudo-exfoliation glaucoma (PEG). Various methods, including inverse variance weighted, MR-Egger regression, weighted median, and mode-based estimator, were employed for effect estimation and pleiotropy testing. To enhance result robustness, a sensitivity analysis was performed by excluding proxy single nucleotide polymorphisms. Genetic predisposition for infection has no causal effect on glaucoma: (OR 1.00; 95% CI 0.95-1.06, = 0.980), (OR 0.97; 95% CI 0.86-1.09, = 0.550), and (OR 0.99; 95% CI 0.90-1.08, = 0.766) with POAG, NTG, and PEG, respectively. An inverse MR showed no causal effect of POAG, NTG, and PEG on infection (OR 1.01; 95% CI 0.97-1.05, = 0.693), (OR 1.00; 95% CI 0.98-1.03, = 0.804), and (OR 0.99; 95% CI 0.96-1.01, = 0.363), respectively. Heterogeneity ( > 0.05) and pleiotropy ( > 0.05) analysis confirmed the robustness of MR results. These results indicated that there was no genetic evidence for a causal link between and glaucoma, suggesting that the eradication or prevention of infection might not benefit glaucoma and .