The Epidemiology of Blindness in Latin America

João M. Furtado MD PhD, Van C. Lansingh MD PhD, Marissa J. Carter PhD MA, María F. Milanese MD, Brenda N. Peña MD, Hernán A. Ghersi MD, Paula L. Bote MD, María E. Nano BA MPH, Juan C. Silva MD MPH

Aims: The goal of this review was to determine what is known in each country of the Latin American region in regard to blindness and visual impairment, hence promoting future areas of operational research. Methods: we included all peer reviewed and non peer reviewed articles as well as government documents that provided information about epidemiological aspects about eye disease, blindness and visual impairment in Latin America (LA) from 1985 to date. Data from Hispanics living in the USA was also included.

Results: We found 171 peer reviewed articles indexed in Pubmed and 79 peer reviewed articles indexed in other regional search engines as well as 10 in non peer reviewed sources. Brazil is the country with the highest number of articles (92). Population-based studies like Rapid Assessment of Cataract Surgical Services (RACSS) and Rapid Assessment of Avoidable Blindness (RAAB) were found for 12 countries. Prevalence of bilateral varied from 1.1% in Argentina to 4.1% in Guatemala (Visual Acuity [VA] < 20/400, available correction, subjects ≥ 50 years old). Among the Hispanics living in the USA, prevalence of blindness varied from 0.29% to 0.4% (VA< 20/200, subjects ≥ 40 years old). The major cause of blindness in all of the studies was cataract, and the proportion of blindness due to the disease varied from 40.9% (Brazil) to 68% (Guatemala). Among the barriers to cataract surgery in LA, unawareness of the existence of treatment, cost of surgery and fear are the most common. Diabetic retinopathy, uncorrected refractive errors, glaucoma and age-related macular degeneration are also important causes of blindness and visual impairment in LA. Retinopathy of Prematurity is a leading cause of childhood blindness, although in Brazil ocular toxoplasmosis also plays an important role.

Conclusions: Although the number of ophthalmologists in the area is considered more than adequate according to WHO recommendations, most blindness and visual impairment is still due to avoidable causes, mainly cataract and refractive errors. In USA, Hispanics have a higher percentage of blindness and visual impairment compared to non-Hispanic Whites. There is much more data for a few countries, with data almost absent for several countries and further research is recommended in order to improve available data and mobilize resources to brake down the barriers with the development of appropriate technology and human resources.