Purpose
To describe and analyze the current prevalence and major reasons of low-vision and blindness in a Chinese adult population.
Methods
Population-based,cross-sectional cohort study.We evaluated 10234 eligible subjects≥45 years old (response rate 78.1%) participated in the Taizhou Eye Study,China.Examination of subjects was performed between July 2012 and December 2013 in Taizhou city,Jiangsu Province.Participants underwent detailed ophthalmologic examination including uncorrected visual acuity(UCVA),best corrected visual acuity(BCVA),intraocular pressure(IOP),axial length,slit lamp examination,fundus examination to evaluate the VI.Low-vision and blindness were defined according to World Health Organizaiton(WHO) standard and United States(US) standard respectively.Prevalence and primary causes of low-vision and blindness were analyzed.
Results
On the basis of the WHO standard,the adjusted prevalence of low-vision and blindness were 5.1%(95% confidence interval [CI],5.0-5.3) and 1.0%(95% CI, 0.9-1.1).On the basis of the US standard, the adjusted prevalence of that were 12.8%(95% CI, 12.1-13.5) and 1.5%(95% CI, 1.3-1.8). Based on the WHO standard, the primary causes of bilateral low-vision and blindness were cataract(59.1%,48.5%), pathologic myopia(17.6%,17.2%) and age-related macular degeneration(11.6%,10.1%). The primary causes of monocular low-vision were cataract(55.6%), age-related macular degeneration(12.6%) and pathologic myopia (8.9%), while those of monocular blindness were cataract(46.8%), atrophy of eyeball or prosthetic eye(10.2%) and cornea opacity(7.3%).A further study showed that in adults 45-59 years old(middle-aged people), pathologic
Conclusions
The prevalence of low vision and blindness in Chinese adult population was still high.Cataract was the primary cause of avoidable low vision and blindness.Pathologic myopic and cataract were the leading causes of vision impairment in middle-aged people,while cataract and macular degeneration were the primary causes in young elderly and elderly people.