Influence of Uncorrected Refractive Error and Unmet Refractive Error on Visual Impairment in A Brazilian Population
The purpose of the present study is to determine the reversal of visual impairment and blindness in the population correcting RE and possible associations between RE and individual characteristics.
A cross-sectional study was conducted in nine counties of the western region of state of São Paulo, using systematic and random sampling of households between March 2004 and July 2005.
Individuals aged more than 1 year old were included and were evaluated for demographic data, eye complaints, history, and eye exam, including no corrected visual acuity (NCVA), best corrected vision acuity (BCVA), automatic and manual refractive examination.
A total of 70.2% of subjects had normal NCVA. URE was detected in 13.8%.
Prevalence of 4.6% of optically reversible low vision and 1.8% of blindness reversible by optical correction were found.
UREN was detected in 6.5% of individuals, more frequently observed in women over the age of 50 and in higher RE carriers.
Visual impairment related to eye diseases is not reversible with spectacles. Using multivariate analysis, associations between URE and UREN with regard to sex, age and RE was observed.
The study concluded that Refractive Error is an important cause of reversible blindness and low vision in the Brazilian population.