Prevalence and Outcomes of Cataract Surgery: the Brazilian Amazon Region Eye Survey (BARES)

Abstract

Purpose : To investigate the prevalence and visual acuity (VA) outcomes of cataract surgery in Parintins city, Brazilian Amazon Region.

Methods : Cluster sampling based on geographically-defined census sectors was used in randomly selecting individuals ≥45 years of age for visual acuity measurement, refraction, slit-lamp examination and fundoscopy during 2014-2015. Participants were queried as to the year and place of previous cataract surgery. The surgical procedure and any evidence of surgical complications were recorded during the examination. The principal cause of visual impairment/blindness was identified for eyes presenting with VA <20/32.

Results : A total of 2383 eligible persons were enumerated and 2042 (85.7%) were examined. A group of 176 persons had been operated on for cataract in one or both eyes (133 from urban areas and 43 from rural areas), representing a cataract surgery prevalence of 8.62% [95% C.I:7.44-9.93] and a total of 275 eyes: 99 both eyes (79 urban and 20 rural) and 77 one eye (54 urban and 23 rural). Cataract surgery prevalence for urban areas was 11.27% [95% C.I.: 9.52-13.22] and for rural areas was 4.99% [95% C.I.: 3.64-6.67]. Surgical coverage among those with presenting visual impairment or blindness ≤20/40 in both eyes because of cataract was 31.8%. Higher schooling and urban area of residence were significantly associated with higher surgical coverage (p<0.01). Among 275 cataract-operated eyes, 43.3% presented with VA >20/40, 16.7% with VA 20/40 to 20/63, 19.3% with VA <20/63 to 20/200, and 20.7% with VA <20/200. With best-correction, the corresponding percentages were 59.3%, 10.0%, 13.3%, and 17.4%. Intra-ocular lenses were found in 92.3% of cataract-operated eyes, and 171 (62.2%) eyes had phacoemulsification. Next to refractive error, age-related macular degeneration and posterior capsule opacity were the main causes of vision impairment/blindness in operated eyes.

Conclusions : The volume of cataract surgery in rural areas of Parintins city is low, with many remaining visually impaired/blind because of cataract. Refractive error and other causes of visual impairment amenable to treatment are common in cataract-operated eyes from both urban and rural areas. Greater emphasis on the quality of visual acuity outcomes along with sustained government subsidy to provide access to cataract surgery is needed.

This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.