Current Prevalence of Myopia and Association of Myopia With Environmental Factors Among Schoolchildren in Japan

Abstract

IMPORTANCE Given the estimates of increasing prevalence of myopia, especially in Asia, it is important to determine the current prevalence of myopia among populations of schoolchildren in Japan.OBJECTIVE To investigate the current prevalence rate of myopia and the association between environmental factors and myopia in Japanese schoolchildren. DESIGN, SETTING, AND PARTICIPANTSThis cross-sectional study assessed 1478 participants, including 726 elementary school students and 752 junior high school students, at 2 schools in Tokyo, Japan, who underwent eye examinations from April 1 to May 31, 2017, that included measurement of the refractive errors by autorefractometry with noncycloplegic refraction and ocular biometric factors. After excluding those who had been treated with atropine or orthokeratology (n = 11), had a history of eye disease (n = 2), had no parental consent (n = 41), and were absent (n = 8), 1416 schoolchildren were analyzed. MAIN OUTCOMES AND MEASURESThe primary outcome was the prevalence of myopia and high myopia. Secondary outcomes were environmental factors that were associated with myopia.RESULTS A total of 1416 schoolchildren (mean [SD] age, 10.8 [2.7] years; 792 [55.9%] male) were studied. The prevalence rates of myopia (spherical equivalent Յ−0.5 diopters [D]) were 76.5% (95% CI, 73.4%-79.7%) among the elementary school students and 94.9% (95% CI, 93.3%-96.5%) among the junior high school students. The prevalence rates of high myopia (spherical equivalent Յ−6.0 D) were 4.0% (95% CI, 2.5%-5.4%) among the elementary school students and 11.3% (95% CI, 8.8%-13.7%) among the junior high school students. The prevalence rates of high myopia classified based on axial length of 26.0 mm or longer were 1.2% (95% CI, 0.4%-2.0%) among elementary school students and 15.2% (95% CI, 12.5%-17.8%) among junior high school students. Multiple regression analysis showed that higher-order aberrations and dry eye disease were associated with refractive error in elementary school students (spherical aberration: β = 6.152; 95% CI, 3.

Prevalence of myopia and vision impairment in school students in Eastern China

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Ratio of Axial Length to Corneal Radius in Japanese Patients and Accuracy of Intraocular Lens Power Calculation Based on Biometric Data

“…Asia. 47,48 In the future, because this tendency may intensify, it is important to improve the accuracy of refractive calculations in eyes with a high AL/CR ratio.…”

Rationale and protocol for the 7- and 8-year longitudinal assessments of eye health in a cohort of young adults in the Raine Study

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