Primary angle-closure glaucoma. Oculometry, epidemiology, and genetics in a high risk population

Area of Science:

• Ophthalmology
• Genetics
• Epidemiology

Background:

• Primary angle-closure glaucoma (a.c.g.) studies have primarily focused on Caucasian populations.
• The epidemiology and etiology of a.c.g. are less understood, though genetic factors are implicated.
• Eskimos represent a high-risk population for a.c.g.

Purpose of the Study:

• To investigate ocular dimensions, epidemiology, and genetic factors of a.c.g. in Greenland Eskimos.
• To assess the prevalence of a.c.g. and its relationship with ocular parameters in this population.
• To explore the potential genetic basis and adaptive significance of shallow anterior chambers in Eskimos.

Main Methods:

• Oculometric, epidemiologic, and genetic studies were conducted among Greenland Eskimos.
• Ocular dimensions and clinical symptoms of a.c.g. patients were compared to existing data.
• Prevalence rates were estimated, and familial resemblance for ocular parameters was analyzed.

Main Results:

• Eskimo a.c.g. patients exhibit ocular dimensions and symptoms consistent with other ethnic groups.
• The general Eskimo population displays shallower anterior segment dimensions, characteristic of a.c.g. patients.
• A.c.g. prevalence was 1.6% in males and 5.1% in females (≥40 years), correlating with axial anterior chamber depth (ACD).
• Familial studies revealed a genetic determination of anterior chamber size, suggesting a genetic basis for a.c.g.
• Shallow anterior chambers in Eskimos may be a genetic adaptation to the arctic environment for corneal protection.

Conclusions:

• Ocular dimensions in Eskimo a.c.g. patients align with global findings, but the general Eskimo population exhibits shallower anterior chambers.
• Genetic factors significantly determine anterior chamber size, likely underpinning the predisposition to a.c.g. in Eskimos.
• The observed ocular traits may represent a genetic adaptation to the arctic environment, with a.c.g. being a potential consequence in older individuals.