Bidirectional genetic link exists between myopia, POAG

Myopia and primary open-angle glaucoma (POAG) share a strong bidirectional, genetic, causal relationship, which is primarily driven by intraocular pressure (IOP), suggest the results of a study.

“This study used Mendelian randomization (MR) analysis to determine genetic causal associations among myopia, glaucoma, and glaucoma-related traits that overcome the effects of external confounders,” the authors said.

To examine the associations between myopia and refractive spherical equivalent, POAG, and POAG endophenotypes, the authors analysed data from the largest publicly available genetic banks. They employed several MR models and multivariate genomic structural modeling to identify significant mediators for the association between POAG and myopia.

Consistent bidirectional genetic association existed between myopia and POAG, as well as between myopia and IOP, based on multiple MR models at Bonferroni-corrected levels of significance. Notably, IOP demonstrated the strongest mediation effect on RSE and POAG (Sobel test, 0.13; 95 percent confidence interval, 0.09‒0.17; p=1.37 × 10^–8).

“Our findings suggest that IOP-lowering treatment for glaucoma may be beneficial in myopic eyes, despite the challenges of establishing a clear clinical diagnosis,” the authors said.

Earlier studies reported a higher risk of POAG in myopic eyes, but their evidence for this finding was inconsistent. This was probably due to confounding factors arising from myopia that complicate clinical tests for glaucoma, according to the authors.