A review of environmental risk factors for myopia during early life, childhood and adolescence.
Myopia is a significant public health problem worldwide, particularly in East Asian countries. The increasing prevalence of myopia poses a huge socio-economic burden and progressive high myopia can lead to sight-threatening ocular complications. Hence, the prevention of early-onset myopia progressing to pathological high myopia is important. Recent epidemiological studies suggest that increased outdoor time is an important modifiable environmental factor that protects young children from myopia. This protective effect may be due to high light intensity outdoors, the chromaticity of daylight or increased vitamin D levels. This review summarises the possible underlying biological mechanisms for the protective association between time outdoors and myopia, including the potential role of nicotinic acetylcholine receptors in refractive error development. Recent evidence for the role of other environmental risk factors such as near work, birth seasons, parental smoking and birth order are also summarised.
Saw Swee Hock School of Public Health, National University of Singapore, Singapore.
Dharani
D
Ramamurthy
Myopia Unit, Singapore Eye Research Institute, Singapore.
Sharon Yu
SY
Lin Chua
Saw Swee Hock School of Public Health, National University of Singapore, Singapore. seang_mei_saw@nuhs.edu.sg.|Myopia Unit, Singapore Eye Research Institute, Singapore. seang_mei_saw@nuhs.edu.sg.
Seang-Mei
SM
Saw
D000293:Adolescent; D002648:Child; D014943:Global Health; D006801:Humans; D009216:Myopia / Q000453:epidemiology / Q000209:etiology / Q000503:physiopathology; D015995:Prevalence; D012029:Refraction, Ocular / Q000502:physiology*; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors; D011795:Surveys and Questionnaires
children's vision; myopia; risk factors