Causal relationship between Helicobacter pylori infection and IgA nephropathy: a bidirectional two-sample mendelian randomization study

Abstract

IgA nephropathy (IgAN) is one of the most common primary glomerulonephritis, and serum Helicobacter pylori (H. pylori) antibody levels are increased in patients with IgA N, but the role of H. pylori infection in the pathogenesis of IgAN is unclear. In this study, we investigated whether there is a causal relationship and reverse causality between IgAN and H. pylori infection by using a bidirectional two-sample Mendelian randomization (MR) analysis. This study was estimated using inverse variance weighted (IVW), MR-Egger and weighted median methods, with the IVW method having the strongest statistical efficacy. Seven common serum H. pylori antibodies were selected as exposure factors for positive MR analysis. The results showed that there was no evidence of a causal relationship between H. pylori infection and IgAN. Reverse MR analysis showed that there was also no evidence that the occurrence of IgAN leads to an increased risk of H. pylori infection.

Keywords:

• IgA nephropathy
• Helicobacter pylori infection
• Mendelian randomization
• Genome-wide association studies
• causality

Acknowledgements

We thank all the participants in this study. We thank all contributors to the GWAS database.

Authors’ contributions

S.J. designed the study and wrote the manuscript. L.L. performed the data extraction. J.L. and J.P. analyzed and interpreted the data. X.Q. performed the project management, comparison and review. All authors read and approved the final manuscript.

Disclosure statement

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as potential conflicts of interest.

Data availability statement

The data we used are publicly available summary statistics and can be obtained upon reasonable request.

Additional information

Funding

This work was supported by the Fund Program for the Scientific Activities of Selected Returned Overseas Professionals in Shanxi Province [Grant no. 2017-29] (Additional file2), and a Research Project Supported by Shanxi Scholarship Council of China [2020-186] (Additional file3).