Blood arsenic levels and heart valve disease: A Mendelian randomization study

Background: Arsenic is a common environmental pollutant and its harmful effects on human health have been confirmed in several studies. However, the exact relationship between blood arsenic levels and heart valve disease remains controversial. Although some studies suggest that arsenic exposure may increase the risk of heart valve disease, there is a lack of sufficient evidence to clarify the mechanism and strength of this association. Methods: In the present study we performed a Mendelian randomization study with R using the genome-wide association studies (GWAS) database of blood arsenic levels and heart valve disease from East Asian samples. Inverse variance weighting (IVW) was used to assess the primary outcomes, and MR Egger, Weighted median, and Weighted mode(WME) analyses were used to ensure the robustness of the results. Sensitivity analyses were performed using MR-Egger, WME, and MR polytomous residuals and outliers (MR-PRESSO) techniques. Finally, co-localization was used to identify the most significant SNPs in this study. Results: MR showed a genetic correlation between elevated blood arsenic levels and the development of heart valve disease (OR: 1.39, 95% CI: 1.10-1.75, P: 5.58×10-3). GWAS co-localization results showed a common genetic factor between the two (PP.H1 =0.78) and a significant SNP: rs76256391. Sensitivity analyses showed no evidence of heterogeneity or pleiotropy in the reported results. Moreover, the inverse MR analysis found no correlation between the two Conclusions: These results show the stability of the study's findings that elevated levels of arsenic in the blood increase the risk of heart valve disease