Causes of childhood blindness in the People's Republic of China: results from 1131 blind school students in 18 provinces

Abstract

Aims-To determine the anatomical site and underlying causes of blindness and severe visual impairment in children under 16 years of age in special education in the People's Republic of China with a view to determining potentially preventable and treatable causes. Methods-A national study of children attending schools for the blind in China was conducted between April and June 1998 using the WHO Prevention of Blindness Programme (WHO/PBL) eye examination record for children with blindness and low vision. Eight Chinese ophthalmologists attended a training workshop before conducting the study. 36 blind schools in 18 provinces of China were included. Results-1245 children aged between 5 and 15 years were examined, of whom 1131 (91%) were blind or severely visually impaired (visual acuity less than 6/60 in the better eye). The commonest anatomical sites of visual loss were whole globe (mainly microphthalmos) 25.5% and retina (mainly dystrophies) 24.9%. Lens was the major site in 18.8%, optic nerve in 13.6%, and glaucoma in 9%. Corneal scarring was not a major cause of visual loss. The aetiology was unknown in 52.9%, hereditary factors were responsible in 30.7%, and childhood causes in 14%. 15% of cases were considered potentially preventable and 22.5% potentially treatable. Conclusion-The pattern of childhood blindness seen in this study is likely to reflect the improved health and socioeconomic status of China but may partly reflect bias in admission to, and location of, blind schools, with higher socioeconomic groups overrepresented. Nutritional and infective causes of blindness are uncommon, and hereditary and unknown factors are now the predominant causes. (Br J Ophthalmol 1999;83:929-932) For a child who is born blind or who becomes blind the total number of years of disability are greater than for a person who becomes blind later in life. Currently it is estimated that there are 1.5 million blind children in the world, of whom one million live in Asia. In order to set priorities for control programmes, baseline epidemiological data of the prevalence and major causes of childhood blindness are required. These are known to vary between regions and countries.1 No data are available for China.The WHO Prevention of Blindness Programme with the International Centre for Eye Health has developed a standard methodology and reporting form to record the causes of visual loss in children with the emphasis on the identification of preventable or treatable causes of blindness. This methodology has now been used in many countries. 2China has a population of 1200 million (1996) of which 378 million are under 18 years of age. China's 22 provinces, five autonomous regions, and 5000 islands are governed from Beijing. (Hong Kong has a special status.) The population is mainly Han Chinese (over 90%) but there are also 200 diVerent ethnic minority groups. The country has a literacy rate of 82%. Health indicators have shown a marked improvement in recent years-for example, the infant mortality (under 1 year) has improved f...

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