There appears to be a genetic-based association between the presence of myopic refractive error and an increased risk of primary open-angle glaucoma (POAG), according to the results of a Mendelian randomization study.
The study examined shared genetic influences for the two ophthalmic condition and evaluated the association between mean spherical equivalent (MSE) refractive error (continuous trait) or myopia (binary trait) and POAG risk among individuals from the Genetic Epidemiology Research on Adult Health and Aging (GERA) cohort.
Researchers used genome-wide association studies (GWAS) of MSE refractive error or myopia conducted in 102,117 UK Biobank participants and a previous GWAS that included 3,836 POAG patients and 48,065 controls from GERA. They applied a two-sample Mendelian randomization to establish potential causal effects between the two eye conditions.
A total of 54,755 non-Hispanic White individuals (58 percent women) were included in the data analyses. Of these, 4,047 individuals had POAG, with this group being older than the 50,708 non-POAG controls (mean age 73.64 vs 65.38 years). The POAG group also had a lower refractive MSE and were more likely to have myopia or high myopia compared with controls (40.2 percent vs 34.1 percent for myopia; 8.5 percent vs 6.8 percent for high myopia).
In genetic correlation analyses, POAG showed a genetic association with MSE refractive error (rg, −0.24; p=3.90 × 10−5), myopia (rg, 0.21; p=0.004), and high myopia (rg, 0.23; p=0.01). Genetically assessed refractive MSE had a negative association with POAG risk (per dioptre more hyperopic MSE: odds ratio, 0.94, 95 percent confidence interval [CI], 0.89–0.99; p=0.01).
The present data support POAG risk stratification and screening strategies, based on refractive error information.