Self-reported myopia and age-related cataract: a two-sample Mendelian randomization study

Our study aims to investigate whether there is evidence for a causal relationship between self-reported myopia and age-related cataract (ARC). A two-sample Mendelian randomization study was performed to identify the causal associations of self-reported myopia with ARC. We used summary-level genetic association data from the MR-Base (Mendelian Randomization-Base) platform on self-reported myopia and ARC. 26 single-nucleotide polymorphisms (SNPs) associated with self-reported myopia were used as instrumental variables. The inverse-variance weighted (IVW) method was applied to perform the primary analysis, and the weighted median method, MR-Egger regression, and Maximum likelihood methods were selected as supplementary analysis. To ensure the reliability of the results, we also performed the sensitivity analysis and MR-PRESSO analysis to assess the heterogeneity and horizontal pleiotropy. Our results provided evidence for a causal effect of self-reported myopia on ARC risk (IVW: OR 10.657, 95% CI (3.175-35.776), P < 0.001). The results of the weighted median method, MR-Egger regression and Maximum likelihood methods were consistent with the result of the IVW method. No evidence of heterogeneity and horizontal pleiotropy was found by the sensitivity analysis and MR-PRESSO analysis. This study demonstrated that self-reported myopia increases the risk of ARC and provided evidence to support public health interventions to prevent the onset and progress of myopia and develop new therapeutic strategies for myopia. Further large-scale prospective studies are required to validate our findings.