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A comparative assessment of avoidable blindness and visual impairment in seven Latin American countries: prevalence,
Juan Carlos Silva1, Oscar J Mújica2, Enrique Vega2
1Pan American Health Organization, Bogotá, Colombia.
Objective:
To conduct a comparative analysis of social inequalities in eye health and eye health care and generate baseline evidence for seven Latin American countries as a benchmarking exercise for monitoring progress toward three goals of the regional Plan of Action for the Prevention of Blindness and Visual Impairment: increasing eye health service coverage, minimizing barriers, and reducing eye health-related disease burden.
Methods:
Results from cross-sectional eye health surveys conducted in six Latin American countries (Argentina, El Salvador, Honduras, Panama, Peru, and Uruguay) from 2011 to 2013 and recently published national surveys in Paraguay were analyzed. The magnitude of absolute and relative inequalities between countries in five dimensions of eye health across the population gradient defined by three equity stratifiers (educational attainment, literacy, and wealth) were explored using standard exploratory data analysis techniques.
Results:
Overall prevalence of blindness in people 50 years old and older varied from 0.7% (95% CI: 0.4-1.0) in Argentina to 3.0% (95% CI: 2.3-3.6) in Panama. Overall prevalence of visual impairment (severe plus moderate) varied from 8.0% (95% CI: 6.5-11.0) in Uruguay to 14.3% (95% CI: 13.9-14.7) in El Salvador. The main reported cause of blindness was unoperated cataract and most cases of visual impairment were caused by uncorrected refractive error. Three countries had cataract surgical coverage of more than 90% for blind persons, and two-thirds of cataract-operated patients had good visual acuity.
Conclusions:
Blindness and moderate visual impairment prevalence were concentrated among the most socially disadvantaged, and cataract surgical coverage and cataract surgery optimal outcome were concentrated among the wealthiest. There is a need for policy action to increase services coverage and quality to achieve universality.
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