Prevalence of eye diseases and causes of visual impairment in school-aged children in Western China

• Published in: Journal of epidemiology Vol. 22; no. 1; pp. 37 - 44
• Main Authors: Pi, Lian-Hong, Chen, Lin, Liu, Qin, Ke, Ning, Fang, Jing, Zhang, Shu, Xiao, Jun, Ye, Wei-Jiang, Xiong, Yan, Shi, Hui, Zhou, Xi-Yuan, Yin, Zheng-Qin
• Format: Journal Article
• Language: English
• Published: Japan Japan Epidemiological Association 01.01.2012
• Subjects: Adolescent; Blindness; Child; Children & youth; China - epidemiology; Clinical Epidemiology; Cluster Analysis; Epidemiology; Eye diseases; Eye Diseases - epidemiology; Female; Humans; Male; Original; Prevalence; Refractive Errors - complications; Refractive Errors - epidemiology; Vision Disorders - epidemiology; Vision Disorders - etiology; China
• ISSN: 0917-5040; 1349-9092
• DOI: 10.2188/jea.JE20110063

The present study investigated the prevalence of refractive error, visual impairment, and eye diseases in school-aged children in western China. The survey was done in a representative county (Yongchuan District, Chongqing Municipality) of western China. Cluster random sampling was used to select children aged 6 to 15 years. We conducted door-to-door surveys and eye examinations including optometry, stereoscopic vision test, eye position and eye movement, slit lamp examination of the anterior segment, retinoscopy, and fundus examination after cycloplegia with 1% cyclopentolate. Among 3469 children, data were available for 3079 (88.76%). The prevalences of eye diseases were, in descending order, refractive error (20.69%; 637/3079), conjunctivitis (11.76%; 362/3079), amblyopia (1.88%; 58/3079), color vision defect (0.52%; 16/3079), keratitis (0.36%; 11/3079), strabismus (0.29%; 9/3079), cataract (0.23%; 7/3079), pathologic myopia (0.19%; 6/3079), and ocular trauma (0.13%; 4/3079). The prevalence of corneal leucoma, corneal staphyloma, optic neuropathy, macular degeneration, and myelinated nerve fibers was 0.03% (1/3079) for each. The prevalence of visual impairment was 7.70% (237/3079), and the major causes of visual impairment were uncorrected refractive error (86.08%; 204/237), amblyopia (9.70%; 23/237), pathologic myopia (1.27%; 3/237), congenital cataract (0.42%; 1/237), and others (2.11%; 5/237). Among school-aged children in a less developed area of western China, refractive error was the most prevalent eye disorder, and uncorrected refractive error was the main cause of visual impairment.