Age, gender, biometry, refractive error, and the anterior chamber angle among Alaskan Eskimos

Abstract

Eskimos do seem to have shallower ACs than do other racial groups. Measurements of the AC angle seem to decline more rapidly over life among Eskimos than among blacks or whites, a phenomenon also observed by us among Chinese, another group with high ACG prevalence. This apparent more rapid decline may be due to a cohort effect with higher prevalence of myopia and resulting wider angles among younger Eskimos and Chinese.

Racial and Ethnic Differences in Ocular Anatomy

“…In concordance with other studies, [44][45][46] Wojciechowski and associates 20 recently found Inuit subjects to have shallower peripheral and central anterior chambers than Chinese, blacks, and whites (p < .01). Of great interest is that the age-adjusted measurements of visible angle structures were significantly smaller for the Inuit subjects and showed a significantly more rapid decline in angle (along with anterior chamber depth) with age than whites and blacks.…”

“…Again, to the contrary, a recent biometric comparative study found that Inuits tended on average to be more hyperopic and have flatter radii of corneal curvatures but also tended to have longer ALs than did blacks, Chinese, and whites. 20 There have been sporadic studies on ethnic prevalence of refractive errors. [21][22][23][24][25] This is due to the fact that it is a monumental task to compare data between races, owing to confounding factors that may affect the prevalence of myopia, such as education, geographical area, and different socioeconomic and educational status.…”

“…Understanding the anatomical variations is of great value especially in screen- 42,43 were found to have shallower angleanterior chambers than did other races. 20,[44][45][46] It has been reported that Far East Asians have an incidence of PACG around 1%, which is a 10-times-higher incidence of PACG than that of whites. 19,47 It is possible that PACG affects 30 million Asian people worldwide.…”

Racial and Ethnic Differences in Ocular Anatomy

“…52 A smaller lens may explain a relatively lower incidence of acute closure attacks in some black populations. 52,53 Wojciechowski and associates 20 found that an Inuit population (that has a higher incidence of anterior chamber angle closure) had significantly thicker lenses than did Chinese, black, and white populations. Owing to the presence of many confounding factors and only cross-sectional analysis, no study has yet shown a true racial anatomical difference in lens size or shape.…”

“…Therefore, Inuits may have the higher incidence of PACG from having shallower and narrower angles, possibly affected by lens size. As stressed by Wojciechowski and associates, 20 long-term prospective studies are needed to control for confounding factors, such as earlier cataract formation and lens swelling in some groups that may be more prevalent with different diets and ultraviolet light exposure levels. There may be a cohort effect in Inuit and Chinese, with younger subjects having deep angles (being more myopic) induced from educational-near work stresses that may cause it to appear that angles are narrowing with age in a population.…”