By Mok Hao Ting, Yong Loo Lin School of Medicine, National University of Singapore
Myopia, also known as near-sightedness, is a refractive error of the eye and is commonly associated with good near vision but poor distance vision. Those who have myopia are also at higher risk of developing myopic macular degeneration which can cause visual impairment. With an increasingly high prevalence of myopia in Singapore and other urban countries, it has become one of the leading causes of blindness and is a major public health concern that should be addressed.
Professor Saw Seang Mei, Head of Myopia Unit in Singapore Eye Research Institute and Professor of Epidemiology at Saw Swee Hock School of Public Health, was an invited guest speaker at the Singapore Primary Eye Care Symposium (SPECS) 2019 held on 23-24 July at One Farrer Hotel. Her Lecture, ‘Changing Paradigm in Myopia: Epidemiology and Socioeconomic Costs’, analyses the prevalence and risk factors of myopia, and treatment costs of myopia in Singapore.
Based on current statistics, 83% of National Service (NS) men are myopic, and 50% are at risk of myopia. Moreover, children are facing a higher risk of developing myopia, with the average age of onset at eight and a half years old. Early onset myopia may further lead to increased risk of developing high myopia, which is closely related to macular degeneration and blindness. It is thus evident that myopia is a disease of the future in Singapore.
The Singapore study of the risk factors for myopia (SCORM) highlights the increasing rates of myopia in primary school students, with 70% of 11 to 18 year olds being myopic. SCORM is an extensive and comprehensive evaluation of risk factors, and includes yearly eye examinations comprising of logMAR visual acuity, auto-refraction measurements with cycloplegic eye drops instilled and A-scan biometry. Myopia is a common eye condition in East Asians and affects a significant proportion of school children.
Professor Saw also compared the prevalence of myopia between school children in Singapore and Sydney, and drew a correlation between an increase in outdoor exposure time and a decline in the prevalence of myopia. Light data and activity recorded in students studying in Singapore were relatively limited as compared to students in Sydney with longer and more frequent light spurts. The prevalence of myopic children in Sydney is also significantly lower than in Singapore.
Professor Saw concluded her lecture by discussing the costs of myopia in Singapore, which includes the use of spectacles and contact lenses, optometry services, transport and LASIK. The estimated cost of treatment of myopia in Singapore is $700 per person, and a projected cost of $200 million across all ages per year. By bringing down the prevalence rate of myopia, it decreases the costs of treating myopia for the government, with an average saving of $80 million a year. Outdoor exposure time is a modifiable risk factor for myopia, and is one way to reduce the prevalence of myopia in Singapore.