High myopia may be predictive of open-angle glaucoma (OAG), according to a study published in the British Journal of Ophthalmology. Secondary findings revealed that advanced age, increased intraocular pressure (IOP), increased vertical cup/disc ratio (VCDR), longer axial length, and thinner central corneal thickness (CCT) were additional risk factors.
Researchers included 2494 of 4439 participants aged 40 years or older who participated in the 2001 Beijing Eye Study. They interviewed all participants and performed comprehensive eye exams. Investigators found OAG in 75 individuals who did not have glaucoma at baseline 10 years prior, and noted that 10-year OAG incidence was 1.8% in those aged between 40 and 49 years, and 5.9% in those aged between 70 years or more.
The team noted that degree of myopia correlated with incidence of OAG. OAG incidence was greatest in the high myopia group (13.3±6.3%, OR: 7.3; 95% CI, 3.3-16.3), followed by the moderately myopic group (8.1±4.3%, OR: 4.2; 95% CI, 2.0-8.8), and low myopic group (6.2±2.8%, OR:3.2; 95% CI, 1.7-5.8). Incidence was lowest in the emmetropic/ hyperopic group (2.1±0.8%). Overall, researchers established that high myopia heightened the incidence of OAG by 7.3 times compared with the incidence in emmetropic eyes.
Multivariable analysis revealed that higher OAG incidence was associated with older age (OR: 1.06; 95% CI, 1.03-1.09), longer axial length (OR: 1.72; 95% CI, 1.45-2.05), higher baseline IOP (OR: 1.18; 95% CI, 1.08-1.29), higher VCDR (OR: 60.8; 95% CI, 6.7-556), and thinner CCT (OR: 0.98; 95% CI 0.97-0.99).
Study limitations include a low participation rate (66.4%), failure to use perimetry to assess glaucoma at the study’s end, confounding due to outcomes following cataract surgery, and ethnic homogeneity among participants which may result in different outcomes for the global community as a whole.
Wang YX, Yang H, Wei CC, Xu L, Wei WB, Jonas JB. High myopia as risk factor for the 10-year incidence of open-angle glaucoma in the Beijing Eye Study. Br J Ophthalmol. Published online February 22, 2022. doi: 10.1136/bjophthalmol-2021-320644.