Analysis Of Ametropia Condition In School-aged Children In Shantou Area Before And After Ten Years

Objective:To provide the data of ametropia condition of school-aged children in Shantou area,and compare the difference in the prevalence of ametropia between 2009-2010 and 2018-2019,and analyze the related risk factors.Methods:The data used in this study was collected from two cross-sectional screening programs in Shantou,China,from 2009-2010 and 2018-2019,which including 7,056 and 14,910 students aged from 6 to 18 years old separately.According to the results of uncorrected visual acuity(UCVA)test and non-cycloplegic autorefraction,the definition of refractive errors were all based on UCVA<0.8.Myopia was defined as spherical equivalent refraction(SER)≤-0.5 diopters(D)and further divided into mild(-3.0 D<SER≤-0.5 D),moderate(-6.0 D<SER≤-3.0 D)and high(SER≤-6.0 D)myopia.Astigmatism was defined as negative cylinder power no more than-0.75 D and stratified as with-the-rule(WTR,negative cylinder axis within 30°of 180°),against-the-rule(ATR,negative cylinder axis within 30°of 90°)and oblique(other axis).Base on spherical refractive error(SRE),astigmatism was stratified as myopic astigmatism(SRE≤-0.5 D),simple astigmatism(-0.5D<SRE≤0.5D),and hyperopic astigmatism(SRE≥0.5D).Variance Analysis,Mann-Whitney U test andχ~2test were used to evaluate statistical differences between the two screening programs.Log-binomial models were used to calculate the prevalence ratio adjusted by age or gender(APR).Logistic regression were used to analyze the independent factors associated with myopia and astigmatism.Odds ratio(OR)with 95%confidence interval(CI)were reported.Results:The prevalence of myopia was 32.7%in 2009-2010 and 47.7%in 2018-2019(P<0.001).It was 29.0%and 42.8%in males(APR:1.48,95%CI:1.40-1.56,P<0.001)and 36.7%and 52.8%in females(APR:1.44,95%CI:1.37-1.51,P<0.001)in 2009-2010 and 2018-2019 separately.The median of SER in myopic eyes of school-aged children in Shantou area was-3.13(IQR 2.63)D in2018-2019 and-2.75(IQR 2.25)D in 2009-2010(Z=-9.89,P<0.001).The APR of moderate(APR:1.73,95%CI:1.61-1.86)and high(APR:1.99,95%CI:1.71-2.31)myopia between two screening programs were higher than low myopia(APR:1.20,95%CI:1.71-2.31).The prevalence of myopia in females was always higher than males in both screening programs(P<0.001).The prevalence of astigmatism was 10.6%in 2009-2010 and 22.1%in 2018-2019(P<0.001).Myopic astigmatism accounted for the most in astigmatism and changed significantly from 81.9%to 89.2%(P<0.001).Students with older age(2009-2010:OR=0.95,95%CI:0.92-0.97)and being females(2018-2019:OR=0.87,95%CI:0.80-0.95)are associated with low prevalence of astigmatism,while the presence of myopia(2009-2010:OR=14.50,95%CI:11.74-17.91;2018-2019:OR=15.68,95%CI:13.81-17.81)is associated with high prevalence of astigmatism.Conclusion:The prevalence of myopia among school-aged children in Shantou area in2018-2019 was higher and the severity was worser than ten years ago.Moderate and high myopia showed the most significan t differences compared with ten years ago.The prevalence of myopia in females was always higher than males in both screening programs.The prevalence of astigmatism was more than doubled compared with ten years ago.Younger age,being males,the presence of myopia were associated with high prevalence of astigmatism.The higher prevalence of myopia and astigmatism warrants attention,and suggests the occurrence or change of myopia or astigmatism related risk factors in different periods.