Prevalence and outcomes of cataract surgery in Brazil: the São Paulo eye study.

Purpose: To investigate the prevalence and visual acuity (VA) outcomes of cataract surgery in a low- to middle-income population in São Paulo, Brazil.

Design: Population-based, cross-sectional study.

Methods: Cluster sampling was used in randomly selecting those > or =50 years old for VA measurement, refraction, and ocular examination. Participants were queried as to the year and type of facility for previous cataract surgery. Surgical procedure and evidence of surgical complications were noted. Main outcome measures were presenting and best-corrected vision, and the principal cause for eyes presenting with VA < or =20/40.

Results: A total of 4,224 eligible persons were enumerated and 3,678 (87.1%) were examined. The prevalence of cataract surgery was 6.28% (95% confidence interval [CI], 5.29% to 7.27%). Surgical coverage for presenting VA <20/63 in both eyes because of cataract was 61.4%. Unoperated cataract impairment/blindness was associated with older age and lack of schooling. Among the 352 cataract-operated eyes, 41.2% presented with VA >20/40, 28.1% with VA 20/40 to 20/63, 14.2% with VA <20/63 to 20/200, and 16.5% with VA <20/200. With best correction, the percentages were 61.9%, 17.6%, 8.2%, and 12.2%. Intraocular lenses were found in 90.6% of cataract-operated eyes; half appeared to have been operated by phacoemulsification. Refractive error and retinal disorders were the main cause of vision impairment/blindness in operated eyes.

Conclusions: Cataract surgery has increased in São Paulo, but many remain visually impaired/blind because of cataract. Refractive error and other causes of impairment are common in cataract-operated eyes. Emphasis on the quality of VA outcomes and sustained government subsidy to provide access to affordable modern cataract surgery are needed.