Prevalence and causes of blindness and visual impairment in Sudur paschim Province of Nepal

Abstract

Aim To determine the prevalence and causes of blindness and visual impairment among aged 50 years and older population in Sudurpaschim Province of Nepal. Methods A cross sectional study, among population aged 50 years and older using a random multistage cluster sampling procedure. Eligible study participants were enrolled by door-to-door enumeration. Survey team lead by an Ophthalmologist assessed visual acuity, examination of eye and data collection was carried out on tablets installed with mRAAB 7 software. Results The survey examined 4573 out of 4615 subjects enumerated, with a response rate 99.1%. Out of 4573 subjects, 1995 (43.63%) were male and 2578 (56.37%) were female. Among the examined, 2214 (48.4%) were between 50-59 years. The age- and sex-adjusted prevalence of blindness was 0.6% (95% CI 0.3 – 0.87).The age- and sex-adjusted prevalence of severe visual impairment, moderate visual impairment, and early visual impairment were 1.0% (95% CI 0.6 – 1.3), 5.3% (95% CI 4.5 – 6.2) and 7.0% (95% CI 6.0 – 8.0) respectively. The main causes of bilateral blindness were untreated cataract (36.4%), non-trachomatous corneal opacity (24.2%), glaucoma (21.2%), globe or central nervous system abnormalities (9.1%), age related macular degeneration (6.1%) and other posterior segment diseases (3.0%). Conclusion Prevalence of blindness was reduced in the province in comparison to the previous survey. Cataract remains the major cause of blindness, severe visual impairment, and moderate visual impairment followed by corneal opacities and glaucoma. The study suggests more attention to be given for cataract, corneal blindness and glaucoma in future interventions to eliminate blindness.