Causes and Estimated Prevalence of Visual Impairment in the United States

Abstract

Abstract: : Purpose: To estimate the cause-specific prevalence and distribution of blindness and low vision in the United States (US) by age, race/ethnicity and gender, and to estimate the change in these prevalence figures over the next 20 years. Methods: Summary prevalence estimates of blindness (both according to the US definition of ≤ 6/60 best corrected vision in the better eye and the World Health Organization standard of < 6/120) and low vision (< 6/12 best-corrected vision in the better eye) were prepared separately for blacks, Hispanics and whites in 5-year age intervals starting at age 40 years. The estimated prevalence rates were based on recent population-based studies in the United States, Australia, and Europe. These estimates were applied to 2000 US census data, and to projected US population figures for 2020, in order to estimate the number of Americans with visual impairment. Cause-specific prevalence rates of blindness and low vision were also estimated for the different racial and ethnic groups. Results: Based on demographics from the 2000 census, an estimated 936,000 (0.78%) Americans over the age of 40 years were blind (US definition). An additional 2.4 million (1.98%) Americans had low vision. The leading cause of blindness among whites was age-related macular degeneration (54.4% of cases), while among blacks, cataract and glaucoma accounted for greater than 60% of blindness. Cataract was the leading cause of low vision, responsible for approximately 50% of bilateral vision < 6/12 among whites, blacks and Hispanics. The number of blind persons in the US is projected to increase by 70% to 1.6 million by 2020, with a similar rise projected for low vision. Conclusion: Blindness or low vision affects approximately one in 28 Americans over the age of 40 years. The prevalence of visual disabilities will increase markedly over the next 20 years, due to the aging of the US population.

Keywords: aging: visual performance • clinical (human) or epidemiologic studies: pre • clinical (human) or epidemiologic studies: bio