Prevalence and risk factors for refractive errors in an adult inner city population.

PURPOSE To estimate the prevalence of refractive errors among adult black and white Americans and to identify risk factors associated with these refractive errors. METHODS Refractive error was measured in a population-based sample of black and white adults age 40 or older residing in east Baltimore from 1985 through 1988. Aphakic eyes were excluded from analysis. RESULTS The prevalence of myopia varied from 10.5% among black men 80 years and older to 42.1% among white women 40 to 49 years of age. Hyperopia ranged from 11.8% among black men 40 to 49 years to 68.1% among white men 80 years of age and older. Astigmatism ranged from 15.8% to 45.2%, and anisometropia ranged from 2.8% to 8.1%, depending on age, race, and gender. Black persons had less myopia, hyperopia, astigmatism, and anisometropia than did white persons. Myopia (< -0.5 diopter [D] spherical equivalent) declined with age, whereas hyperopia (> +0.5 D), astigmatism (> 0.5 D of cylinder), and anisometropia (> 1.0 D between eyes) increased with age. Myopia increased with increasing years of education, although this association was stronger for white persons than for black persons and among younger subjects. Hyperopia declined with increasing years of education, and this association was stronger among younger than older subjects. Education was not associated with astigmatism or anisometropia. CONCLUSIONS Black persons had lower rates of refractive error than did white persons, except for hyperopia prevalence, which was comparable in black and white women. Refractive errors are common among adult inner city Americans, but rates vary substantially by age, race, gender, and education levels.