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.
Salomao
Solange R
SR
Vision Institute, Department of Ophthalmology, Federal University of Sao Paulo (UNIFESP-Paulista School of Medicine), Sao Paulo, SP, Brazil. ssalomao@oftalmo.epm.br
Cinoto
Rafael W
RW
Berezovsky
Adriana
A
Araujo-Filho
Arnaud
A
Mitsuhiro
Marcia R K H
MR
Mendieta
Luana
L
Morales
Paulo H A
PH
Pokharel
Gopal P
GP
Belfort
Rubens
R
Ellwein
Leon B
LB
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