Prevalence and causes of vision impairment and blindness in older adults in Brazil: the Sao Paulo Eye Study.
OBJECTIVE
Investigate prevalence and causes of vision impairment/blindness in older adults in a low-middle income area of Sao Paulo, Brazil.


METHODS
Cluster sampling, based on geographically defined census sectors, was used in randomly selecting cross-sectionally persons 50 years of age or older. Subjects were enumerated through a door-to-door survey and invited for measurement of presenting and best-corrected visual acuity and an ocular examination. The principal cause was identified for eyes with presenting visual acuity less than 20/32.


RESULTS
A total of 4,224 eligible persons in 2,870 households were enumerated, and 3,678 (87.1%) examined. The prevalence of presenting visual acuity > or = 20/32 in both eyes was 61.6% (95% confidence interval [CI]: 59.4%-63.9%), and 80.4% (95% CI: 78.8%-82.1%) with best correction. The prevalence of visual impairment (< 20/63 to > or =20/200) in the better eye was 4.74% (95% CI: 3.97%-5.53%), and 2.00% (95% CI: 1.52%-2.49%) with best correction. The prevalence of presenting bilateral blindness (< 20/200) was 1.51% (95% CI: 1.20%-1.82%), and 1.07% (95% CI: 0.79%-1.35%) with best correction. Presenting blindness was associated with older age and lack of schooling. Retinal disorders (35.3%) and cataract (28.3%) were the most common causes of blind eyes. Cataract (33.2%), refractive error (32.3%), and retinal disorders (20.3%) were the main causes of vision impairment < 20/63 to > or = 20/200, with refractive error (76.8%) and cataract (12.2%) as main causes for eyes with acuity < 20/32 to > or = 20/63.


CONCLUSIONS
Vision impairment 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.
Vision Institute, Department of Ophthalmology, Federal University of Sao Paulo (UNIFESP-Paulista School of Medicine), Sao Paulo, SP, Brazil. ssalomao@oftalmo.epm.br
Solange R
SR
Salomao
Rafael W
RW
Cinoto
Adriana
A
Berezovsky
Arnaud
A
Araujo-Filho
Marcia R K H
MR
Mitsuhiro
Luana
L
Mendieta
Paulo H A
PH
Morales
Gopal P
GP
Pokharel
Rubens
R
Belfort
Leon B
LB
Ellwein
D017677:Age Distribution; D000368:Aged; D001766:Blindness / Q000453:epidemiology* / Q000209:etiology*; D001938:Brazil / Q000453:epidemiology; D002386:Cataract / Q000150:complications; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012030:Refractive Errors / Q000150:complications; D012164:Retinal Diseases / Q000150:complications; D014786:Vision Disorders / Q000453:epidemiology* / Q000209:etiology* / Q000503:physiopathology; D015348:Vision, Binocular; D014792:Visual Acuity