Visual impairment from age-related cataract among an indigenous African population

Abstract

To determine the magnitude of visual impairment (VI) resulting from lens opacity/cataract among a rural population in southwestern Nigeria. A population-based cross-sectional survey using a multistage sampling method to select subjects >or=50 years. Participants with pinhole visual acuity of <or=6/18 in their better eye, exclusively from lens opacity/cataract, were further examined by an ophthalmologist. Their level of VI was categorised using the International Classification of Disease tenth revision and lens opacity was graded using the World Health Organization's cataract grading system. From the enumerated population of 1200 subjects, 1031 subjects were examined. The prevalence of VI from cataract/lens opacity in the population studied was 11.9% (95% CI: 10.1-14.0) with a cataract blindness prevalence of 2.0% (95% CI: 1.3-3.0). The odds for VI increased with increasing age and female patients had 1.6 times the odds for cataract blindness than did male patients. Mixed cataract was the most prevalent of the visually disabling cataract. (3.9% (95% CI: 2.8-5.2)), whereas posterior subcapsular cataract was the least prevalent (2.5% (95% CI: 1.7-3.7)). VI from cataract remains a public health problem in the Akinyele district of Nigeria. The need for a comprehensive cataract surgical service using the VISION 2020 model is necessary in the district if the burden from the backlog of visually disabling cataract is to be reduced.