Abstract
Purpose
A pilot study to determine the prevalence of myopia, proportion of uncorrected myopia and pertinent environmental factors among children in a suburban region in Canada.
Methods
Refraction with cycloplegia and ocular biometry were measured in children of two age groups. Myopia was considered at a spherical equivalent refraction (SER) ≤−0.50 D in at least one eye. Parents completed a questionnaire that captured the child’s daily activities.
Results
A total of 166 children completed the study (83 aged 6–8 and 83 aged 11–13). Myopia prevalence was 17.5% among the overall group, 6.0% among ages 6–8 and 28.9% among ages 11–13. Mean subjective SER in myopic children was −1.10 D (95% confidence interval (CI), −0.34 to −1.86 D) at ages 6–8 and −2.44 D (95% CI, −1.71 to −3.18 D) at ages 11–13. In this study, 34.5% of the myopic children were uncorrected, which represented 6.0% of the entire group of children. Mean axial length (AL) increased by 1.03 mm from ages 6–8 (mean 22.62 mm; 95% CI, 22.45 to 22.79 mm) to ages 11–13 (mean 23.65 mm; 95% CI, 23.45 to 23.84 mm; p < 0.01). The correlation coefficient between AL and SER was −0.618 (p < 0.01). Binary logistic regression between outdoor time and the prevalence of myopia showed that one additional hour of outdoor time per week lowered the odds of a child having myopia by 14.3% (p = 0.007).
Conclusion
Myopia prevalence increased from 6% at ages 6–8 to 29% at ages 11–13. Thirty-five per cent of the myopes in this study were uncorrected. More time outdoors may be beneficial to protect against myopia onset.
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References
Vitale S, Sperduto RD, Ferris FLI. Increased prevalence of myopia in the United States between 1971-1972 and 1999-2004. Arch Ophthalmol. 2009;127:1632–9.
McCullough SJ, O’Donoghue L, Saunders KJ. Six year refractive change among white children and young adults: evidence for significant increase in myopia among white UK children. PLoS ONE. 2016;11:e0146332.
Lin LL, Shih YF, Hsiao CK, Chen CJ. Prevalence of myopia in Taiwanese schoolchildren: 1983 to 2000. Ann Acad Med Singapore. 2004;33:27–33.
Kleinstein RN, Jones LA, Hullett S, et al. Refractive error and ethnicity in children. Arch Ophthalmol. 2003;121:1141–7.
Vitale S, Ellwein L, Cotch MF, Ferris FLI, Sperduto R. Prevalence of refractive error in the United States, 1999-2004. Arch Ophthalmol. 2008;126:1111–9.
Rose KA, Morgan IG, Ip J, et al. Outdoor activity reduces the prevalence of myopia in children. Ophthalmology. 2008;115:1279–85.
He M, Zeng J, Liu Y, Xu J, Pokharel GP, Ellwein LB. Refractive error and visual impairment in urban children in southern China. Invest Ophthalmol Vis Sci. 2004;45:793–9.
Lam CSY, Edwards M, Millodot M, Goh WSH. A 2-year longitudinal study of myopia progression and optical component changes among Hong Kong schoolchildren. Optom Vis Sci. 1999;76:370–80.
Sun J, Zhou J, Zhao P, et al. High prevalence of myopia and high myopia in 5060 Chinese university students in Shanghai. Invest Ophthalmol Vis Sci. 2012;53:7504–9.
Lim LT, Gong Y, Ah-Kee EY, Xiao G, Zhang X, Yu S. Impact of parental history of myopia on the development of myopia in mainland China school-aged children. Ophthalmol Eye Dis. 2014;6:31–35.
Mutti DO, Mitchell GL, Moeschberger ML, Jones LA, Zadnik K. Parental myopia, near work, school achievement, and children’s refractive error. Invest Ophthalmol Vis Sci. 2002;43:3633–40.
French AN, Morgan IG, Mitchell P, Rose KA. Risk factors for incident myopia in Australian schoolchildren: the Sydney adolescent vascular and eye study. Ophthalmology. 2013;120:2100–8.
Saw SM, Chua WH, Hong CY, et al. Nearwork in early-onset myopia. Invest Ophthalmol Vis Sci. 2002;43:332–9.
Smith EL 3rd. Optical treatment strategies to slow myopia progression: effects of the visual extent of the optical treatment zone. Exp Eye Res. 2013;114:77–88.
Walline JJ. Myopia control: a review. Eye Contact Lens. 2016;42:3–8.
Cruess AF, Gordon KD, Bellan L, Mitchell S, Pezzullo ML. The cost of vision loss in Canada. 2. Results. Can J Ophthalmol. 2011;46:315–8.
Jones D, Luensmann D. The prevalence and impact of high myopia. Eye Contact Lens. 2012;38:188–96.
Klaver CC, Wolfs RC, Vingerling JR, Hofman A, de Jong PT. Age-specific prevalence and causes of blindness and visual impairment in an older population: the Rotterdam Study. Arch Ophthalmol. 1998;116:653–8.
Laatikainen L, Erkkilä H. Refractive errors and other ocular findings in school children. Acta Ophthalmol (Copenh). 1980;58:129–36.
Statistics Canada. Population growths in Canada: From 1851 to 2061 http://www12.statcan.gc.ca/census-recensement/2011/as-sa/98-310-x/98-310-x2011003_1-eng.cfm. Accessed 05 July 2012.
Statistics Canada. Immigrant population by place of birth and period of immigration (2006 Census) http://www.statcan.gc.ca/tables-tableaux/sum-som/l01/cst01/demo24a-eng.htm. Accessed 05 July 2012.
Robinson BE. Factors associated with the prevalence of myopia in 6-year-olds. Optom Vis Sci. 1999;76:266–71.
Hrynchak PK, Mittelstaedt A, Machan CM, Bunn C, Irving EL. Increase in myopia prevalence in clinic-based populations across a century. Optom Vis Sci. 2013;90:1331–41.
Cheng D, Schmid KL, Woo GC. Myopia prevalence in Chinese-Canadian children in an optometric practice. Optom Vis Sci. 2007;84:21–32.
Guo L, Yang J, Mai J, et al. Prevalence and associated factors of myopia among primary and middle school-aged students: a school-based study in Guangzhou. Eye. 2016;30:796–804.
Garcia-Lievanos O, Sanchez-Gonzalez L, Espinosa-Cruz N, Hernandez-Flores L, Salmeron-Leal L, Torres-Rodriguez H. Myopia in schoolchildren in a rural community in the State of Mexico, Mexico. Clin Optom. 2016;8:53–56.
Egashira SM, Kish LL, Twelker JD, Mutti DO, Zadnik K, Adams AJ. Comparison of cyclopentolate versus tropicamide cycloplegia in children. Optom Vis Sci. 1993;70:1019–26.
Breslin DC. Vision loss in Canada 2011. http://www.cos-sco.ca/wp-content/uploads/2012/09/VisionLossinCanada_e.pdf. National Coalition for Vision Health; 2011. Accessed May 24 2016.
Jang JU. The status of refractive errors in elementary school children in south Jeolla Province, South Korea. Clin Optom. 2015;2015:45–51.
Lin LLJ, Hung PT, Ko LS, Hou PK. Study of myopia among aboriginal school children in Taiwan. Acta Ophthalmol (Copenh). 1988;66:34–36.
Holden BA, Fricke TR, Wilson DA, et al. Global Prevalence of myopia and high myopia and temporal trends from 2000 through 2050. Ophthalmology. 2016;123:1036–42.
Williams KM, Bertelsen G, Cumberland P, et al. Increasing prevalence of myopia in Europe and the impact of education. Ophthalmology. 2015;122:1489–97.
O’Donoghue L, Kapetanankis VV, McClelland JF, et al. Risk factors for childhood myopia: findings from the NICER study. Invest Ophthalmol Vis Sci. 2015;56:1524–30.
Jin JX, Hua WJ, Jiang X, et al. Effect of outdoor activity on myopia onset and progression in school-aged children in northeast China: the Sujiatun Eye Care Study. BMC Ophthalmol. 2015;15:73.
Wojciechowski R. Nature and nurture: the complex genetics of myopia and refractive error. Clin Genet. 2011;79:301–20.
Bureau USC. United States Quick Facts. https://www.census.gov/quickfacts/table/PST045215/00. Accessed 18 May 2016.
Statistics Canada. Canada (Code 01) (table). National Household Survey (NHS) Profile. 2011 National Household Survey. http://www12.statcan.gc.ca/nhs-enm/2011/dp-pd/prof/index.cfm?Lang=E. Statistics Canada Catalogue no 99-004-XWE. Accessed 10 May 2016.
Sankaridurg P, Donovan L, Varnas S, et al. Spectacle lenses designed to reduce progression of myopia: 12-month results. Optom Vis Sci. 2010;87:631–41.
Acknowledgements
We thank the two School Boards in the Waterloo Region and their participating schools for their contributions to this study, and Carl Zeiss Canada for providing an IOLMaster on loan. We are grateful to Dominik Papinski for his help with statistical analysis.
Funding
This study was partially funded by a grant from Essilor and by the Centre for Ocular Research & Education, University of Waterloo.
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Yang, M., Luensmann, D., Fonn, D. et al. Myopia prevalence in Canadian school children: a pilot study. Eye 32, 1042–1047 (2018). https://doi.org/10.1038/s41433-018-0015-5
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DOI: https://doi.org/10.1038/s41433-018-0015-5
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