Myopia Differences Between Migrant Children Of Migrant Workers And Urban Children And Adolescents And Study On The Association Between Children Of Migrant Workers And Migrant Time

ObjectiveTo compare the prevalence and differences of self-reported myopia among migrant children of migrant workers,migrant children of urban migrant residents,and children of local residents in Baoan District of Shenzhen,and analyze the impact of the migrant time on prevalence of the self-reported myopia of children of migrant workers.To provide a theoretical basis for the prevention and control of myopia in migrant children and adolescentsMethodsChildren and adolescents from 14 schools in 6 streets in Baoan District of Shenzhen were selected as respondents by purposive sampling between April 2019 to May 2019.All participants completed an anonymous questionnaire to collect the information of demographic characteristics,the status of migration,the status of self-reported myopia,screen time in the last seven days,and outdoor activities in the last month,etc.26 618 copies of questionnaire were valid.Chi-square test was used to compare the differences of self-reported myopia among children and adolescents with different characteristics.After adjusting for gender,outdoor activity,video time,sleep time,school performance,parents’nearsightedness and mode of transportation to school,multi-factor binary classification unconditional logistic regression model was used to analyze the relationship between migrant time in different school segments and the self-reported myopia children and adolescents.ResultsThe prevalence of self-reported myopia in primary and middle school students was 49.4%in Baoan District,Shenzhen,among which the prevalence of self-reported myopia of local residents,migrant children of migrant workers and migrant children of urban migrant residents were 56.9%,42.2%,54.7%,and respectively.The difference in the prevalence of myopia was statistically significant(χ~2=494.42,P<0.001).Chi-square analysis showed that there were statistically significant differences in school duration,outdoor activity time,video time,sleep time,academic performance,paternal myopia,maternal myopia and mode of transportation among the three types of children and adolescents.The differences in self-reported myopia,outdoor activity time,screen time,sleep time,academic performance,myopia of biological father,myopia of biological mother,myopia of biological mother,and the way of transportation to school for children of local residents and children of migrant workers self-reported were statistically significant(P<0.001);There were statistically significant differences in the school period,outdoor activity time,screen time,sleep time,academic performance,myopia of the biological father and the myopia of the biological mother of the children of urban residents who moved with them(P<0.05).Logistic regression analysis showed that after controlling for related confounding factors,compared with children who migrated for 1-2 years,children who migrated for more than 6 years have a higher risk of myopia,odds ratios was1.33(95%CI:1.09～1.62);subjects characterized as the migrant children of migrant workers whose migrant time is more than 6 years had higher risk for self-reported myopia than those characterized as the migrant children of migrant workers whose migrant time is 1-2 years in elementary school grades 1 to 3,odds ratios was1.99(95%CI:1.22～3.27);in the high school group,there is a positive correlation between the migration time and the myopia of migrant children of migrant workers.The longer the migration time,the higher the risk of myopia.Subjects characterized as the migrant children of migrant workers whose migrant time is 3-5 years and more than 6 years had higher risk for self-reported myopia than those characterized as the migrant children of migrant workers whose migrant time is 1-2 years of high school,odds ratios were 6.03(95%CI:1.29～28.15),6.52(95%CI:1.51～28.11),respectively.The time of migration is meaningless for the risk of myopia of migrant children of urban migrant residents in different school segments.In the group of both myopic parents,compared with children of migrant workers who migrated for 1-2 years,children of migrant workers who migrated for more than 6 years had a higher risk of myopia(OR=1.96,95%CI:1.00～3.83);Compared with either myopic parent,children of migrant workers who migrated for 1-2 years,migrant workers who migrated for more than 6 years had a higher risk of myopia(OR=1.64,95%CI:1.03～2.61).Regardless of the myopia situation of parents,there is no significant correlation between the migration time of migrant children of urban migrant residents and the self-reported risk of myopia.ConclusionsThe myopia prevalence of migrant children in Bao’an District of Shenzhen is lower than that of the children of local residents,which may be affected by many factors.Migrant time is only positively related to the myopia of the children of migrant workers,and not related to the myopia of the migrant children of urban residents.Understanding the risk factors related to myopia of migrant workers and children of urban migrants will be helpful to develop differentiated intervention measures to promote the prevention and control of myopia in children and adolescents.