Visual impairment and blindness: an overview of prevalence and causes in Brazil

Abstract

Our purpose is to provide a summary overview of blindness and visual impairment on the context of recent Brazilian ocular epidemiologic studies. Synthesis of data from two cross-sectional population-based studies -the São Paulo Eye Study and the Refractive Error in School Children Study is presented. 3678 older adults and 2441 school children were examined between July 2004 and December 2005. Prevalence of blindness in older adults using presenting visual acuity was 1.51% decreasing to 1.07% with refractive correction. The most common causes of blindness in older adults were retinal disorders, followed by cataract and glaucoma. In school children, the prevalence of uncorrected visual impairment was 4.82% decreasing to 0.41% with refractive correction. The most common cause of visual impairment in school children was uncorrected refractive error. Visual impairment and blindness in Brazil is an important public health problem. It is a significant problem in older Brazilians, reinforcing the need to implement prevention of blindness programs for elderly people with emphasis on those without schooling. In school-children cost-effective strategies are needed to address a readily treatable cause of vision impairment -prescription and provision of glasses.

Avaliação da qualidade de vida de deficientes visuais

“…Visual impairment can be understood as an organic character impediment related to ocular diseases that affect the normal functioning of vision. This can result in the total absence of visual capacity of the individual and can occur with or without the perception of light, which may be inherited or acquired (2) .…”

Influence of uncorrected refractive error and unmet refractive error on visual impairment in a Brazilian population

“…In school children, the prevalence of uncorrected VI was 4.8%, which decreased to 12.4% with refractive correction [22]. …”

Relação do desequilíbrio postural com incapacidade cervical em pessoas com deficiência visual

“…A deficiência visual é caracterizada por perdas parciais ou totais da visão, sendo várias são as causas da perda dessa capacidade, podendo estar relacionada a fatores biológicos e ambientais, levando o indivíduo a uma limitação em seu desempenho habitual (4,12) . O deficiente visual adota posturas inadequadas pela má utilização dos esquemas reflexos relacionados com a postura (13) , pois à medida que a cegueira causa distorções em certos mecanismos (proprioceptivos e tônico na coluna cervical) com o intuito de compensar a falta de visão, gera uma hipotonia ou hipertonia no pescoço, resultando na existência de uma concepção vertical inadequada pela tendência de inclinação do corpo para frente durante a marcha, interferindo na postura que também é afetada pelo conhecimento limitado da imagem corporal (14) .…”