Abstract OBJECTIVE: To study the influence of near-work and outdoor activities on myopia progression in school children. METHODS: Eighty 7-11-year-old school children with myopia were randomly assigned into an intervention group (n=41) and a control group (n=39). The children in the intervention group did near- and middle-vision activities less than 30 hrs per week and more outdoor activities than 14-15 hrs per week. Myopia progression was observed regularly over 2 years after which ophthalmologists administered questionnaires regarding near-vision work (reading, writing and using computer), middle-vision work (watching TV and extracurricular learning activities), outdoor activities, using nature light, wearing glasses, etc. RESULTS: The annual mean myopia progression (0.38±0.15 D) in the intervention group was significantly lower than that in the control group (0.52±0.19 D; P<0.01). The children in the two groups spent similar amounts of time in near-vision activities, but the children in the intervention group spent less time in middle-vision activities (P<0.01) and more outdoor activities (13.7±2.4 vs 6.2±1.6 hrs/wk; P<0.01). When considering all children in the study, there were 4 factors that significantly correlated with less myopia progression: more outdoor activities, more time spent wearing glasses, more time spent in natural light and less time using a computer. When analyzing the intervention group separately, more outdoor activity was inversely correlated with myopia progression (t=-2.510, P<0.05). Separate analysis of the control group indicated that more time wearing glasses was correlated with less myopia progression (t=-3.115, P<0.05). CONCLUSIONS: Myopia progression in school children may be slowed by more outdoor activities, more time spent in natural light and more time wearing corrective glasses.
[2]Saw SM, Chua WH, Hong CY, Wu HM, Chan WY, Chia KS, et al. Nearwork in early-onset myopia[J]. Invest Ophthalmol Vis Sci, 2002, 43(2): 332-339.
[3]Ip JM, Saw SM, Rose KA, Morgan IG, Kifley A, Wang JJ, et al. Role of near work in myopia: findings in a sample of Australian school children[J]. Invest Ophthalmol Vis Sci, 2008, 49(7): 2903-2910.
[4]Rose KA, Morgan IG, Ip J, Kifley A, Huynh S, Smith W, et al. Outdoor activity reduces the prevalence of myopia in children[J]. Ophthalmology, 2008, 115(8): 1279-1285.
[5]Fan DS, Lam DS, Lam RF, Lau JT, Chong KS, Cheung EY, et al. Prevalence, incidence, and progression of myopia of school children in Hong Kong[J] . Invest Ophthalmol Vis Sci, 2004, 45(4): 1071-1075.
[6]He M, Zeng J, Liu Y, Xu J, Pokharel GP, Ellwein LB. Refractive error and visual impairment in urban children in southern china[J]. Invest Ophthalmol Vis Sci, 2004, 45(3): 793-799.
[7]Dirani M, Tong L, Gazzard G, Zhang X, Chia A, Young TL, et al. Outdoor activity and myopia in Singapore teenage children[J]. Br J Ophthalmol, 2009, 93(8): 997-1000.
[8]Rose KA, Morgan IG, Smith W, Burlutsky G, Mitchell P, Saw SM. Myopia, lifestyle, and schooling in students of Chinese ethnicity in Singapore and Sydney[J].Arch Ophthalmol, 2008, 126(4): 527-530.
[9]Jacobsen N, Jensen H, Goldschmidt E. Does the level of physical activity in university students influence development and progression of myopia?--a 2-year prospective cohort study[J]. Invest Ophthalmol Vis Sci, 2008, 49(4): 13221327.
[10]Prepas SB. Light, literacy and the absence of ultraviolet radiation in the development of myopia[J]. Med Hypotheses, 2008, 70(3): 635637.
[11]Czepita D, Gostawski W, Mojsa A. Refractive errors among students occupying rooms lighted with incandescent or fluorescent lamps[J]. Ann Acad Med Stetin, 2004, 50(2): 51-54.
[12]Ashby R, Ohlendorf A, Schaeffel F. The effect of ambient illuminance on the development of deprivation myopia in chicks[J]. Invest Ophthalmol Vis Sci, 2009, 50(11): 5348-5354.
[13]Chung K, Mohidin N, O′Leary DJ. Undercorrection of myopia enhances rather than inhibits myopia progression[J]. Vision Res, 2002, 42(22): 2555-2559.
[14]Cochrane GM, du Toit R, Le Mesurier RT. Management of refractive errors[J]. BMJ, 2010, 340: c1711.
[15]Lin Z, Martinez A, Chen X, Li L, Sankaridurg P, Holden BA, et al. Peripheral defocus with single-vision spectacle lenses in myopic children[J]. Optom Vis Sci, 2010, 87(1): 4-9.
[16]Marsh-Tootle WL, Dong LM, Hyman L, Gwiazda J, Weise KK, Dias L, et al. Myopia progression in children wearing spectacles vs. switching to contact lenses[J]. Optom Vis Sci, 2009, 86(6): 741-747.
[17]Mutti DO, Zadnik K. Is computer use a risk factor for myopia? [J]. J Am Optom Assoc, 1996, 67(9):521-530.
[18]Basso A, Di Lorenzo L, Cramarossa AA, Corfiati M, Ria W, Bellino R, et al. Evaluation of myopia in a group of people working with video terminals: first results[J]. G Ital Med Lav Ergon, 2006, 28(2): 207-209.
[19]Morgan IG, Rose KA, Ellwein LB. Is emmetropia the natural endpoint for human refractive development? An analysis of population-based data from the refractive error study in children (RESC) [J]. Acta Ophthalmol, 2010, 88(8): 877-884.