Prevalence and Risk Factors for Refractive Errors in Adult Chinese in Singapore

• Published in: Investigative ophthalmology & visual science Vol. 41; no. 9; pp. 2486 - 2494
• Main Authors: Wong, Tien Yin, Foster, Paul J, Hee, Joscelin, Ng, Tze Pin, Tielsch, James M, Chew, Sek Jin, Johnson, Gordon J, Seah, Steve K. L
• Format: Journal Article
• Language: English
• Published: Rockville, MD ARVO 01.08.2000; Association for Research in Vision and Ophtalmology
• Subjects: Adult; Age Distribution; Aged; Aged, 80 and over; Biological and medical sciences; China - ethnology; Diseases of visual field, optic nerve, optic chiasma and optic tracts; Female; Humans; Male; Medical sciences; Middle Aged; Ophthalmology; Prevalence; Refractive Errors - ethnology; Risk Factors; Sex Distribution; Singapore - epidemiology; Asia; China; Singapore; Human; Eye disease; Prevalence; Vision disorder; Risk factor; Myopia; Refractive error; Adult; Epidemiology
• ISSN: 0146-0404; 1552-5783

To determine the epidemiology of refractive errors in an adult Chinese population in Singapore. A disproportionate, stratified, clustered, random-sampling procedure was used to select names of 2000 Chinese people aged 40 to 79 years from the 1996 Singapore electoral register in the Tanjong Pagar district in Singapore. These people were invited to a centralized clinic for a comprehensive eye examination, including refraction. Refraction was also performed on nonrespondents in their homes. Myopia, high myopia, and hyperopia were defined as a spherical equivalent (SE) in the right eye of less than -0.5 D, less than -5.0 D, and more than +0.5 D, respectively. Astigmatism was defined as less than -0.5 D of cylinder. Anisometropia was defined as a difference in SE of more than 1.0 D between the two eyes. Only phakic eyes were analyzed. From 1717 eligible people, 1232 (71.8%) were examined. Adjusted to the 1997 Singapore population, the overall prevalence of myopia, hyperopia, astigmatism, and anisometropia was 38.7% (95% confidence interval [CI]: 35.5, 42.1), 28.4% (95% CI: 25.3, 31.3), 37.8% (95% CI: 34.6, 41.1), and 15.9% (95% CI: 13.5, 18.4), respectively. The prevalence of high myopia was 9.1% (95% CI: 7.2, 11.2), with women having significantly higher rates than men. The age pattern of myopia was bimodal, with higher prevalence in the 40 to 49 and 70 to 81 age groups and lower prevalence between those age ranges. Prevalence was reversed in hyperopia, with a higher prevalence in subjects aged 50 to 69. There was a monotonic increase in prevalence with age for both astigmatism and anisometropia. Increasing educational levels, higher individual income, professional or office-related occupations, better housing, and greater severity of nuclear opacity were all significantly associated with higher rates of myopia, after adjustment for age and sex. The results indicate that whereas myopia is 1.5 to 2.5 times more prevalent in adult Chinese residing in Singapore than in similarly aged European-derived populations in the United States and Australia, the sociodemographic associations are similar.