Genetic risk of primary open-angle glaucoma. Population-based familial aggregation study

Area of Science:

• Ophthalmology
• Genetics
• Public Health

Background:

• Primary open-angle glaucoma (POAG) is a leading cause of irreversible blindness worldwide.
• Familial aggregation studies are crucial for understanding the genetic and environmental factors contributing to POAG.
• Identifying at-risk individuals can facilitate early detection and intervention.

Purpose of the Study:

• To investigate the familial aggregation of POAG within a general population.
• To quantify the absolute and relative risks of POAG for first-degree relatives of affected individuals.

Main Methods:

• A population-based study (Rotterdam Study) included first-degree relatives of POAG patients (n=48) and control subjects (n=155).
• Standardized ophthalmic examinations, including perimetry, were performed.
• Key outcome measures included intraocular pressure, vertical cup-disc ratio, and glaucoma diagnosis based on visual field defects and optic disc appearance.

Main Results:

• The prevalence of glaucoma was significantly higher in relatives of patients (10.4% in siblings, 1.1% in offspring) compared to relatives of controls (0.7% in siblings, 0% in offspring).
• The lifetime risk for glaucoma was substantially increased in relatives of patients (22.0%) versus controls (2.3%), with a risk ratio of 9.2.
• Enlarged cup-disc ratio showed a higher lifetime risk (62.2%) in relatives of patients compared to elevated intraocular pressure (42.5%), suggesting it as an earlier sign.

Conclusions:

• Relatives of individuals with POAG exhibit a markedly elevated risk of developing the disease in the general population.
• An enlarged cup-disc ratio appears to be a more prominent early indicator of familial glaucoma aggregation than elevated intraocular pressure.
• Further research is warranted to elucidate the specific genetic components underlying the observed familial aggregation of POAG.