Cohort study with 4‐year follow‐up of myopia and refractive parameters in primary schoolchildren in Baoshan District, Shanghai

Abstract

ImportanceCohort studies could not only reveal associations between change of refractive components and onset/progression of myopia, but also risk factors, which is important for understanding mechanism and providing strategies.BackgroundPrevalence of myopia is high in Shanghai, being reported to be 52.2% in children aged 10 years old.DesignCohort study.ParticipantsA total of 1856 students from six randomly selected primary schools in Baoshan District, Shanghai.MethodsChildren underwent comprehensive ocular measurement, including axial length (AL), corneal curvature radius and cycloplegic auto‐refraction. Questionnaires about eye usage time were collected. Grade 1 students were followed for 4 years, and grade 2 and 3 students for 2 years.Main Outcome Measures(i) Change of spherical equivalent (SE) and AL and (ii) risk factors for progression and incidence of myopia.ResultsThe average 2‐year progress of SE was 0.91D, 0.91D and 1.11D for grade 1, 2 and 3, respectively, and the average elongation of AL was 0.70 mm, 0.64 mm and 0.71 mm, respectively. Only parental myopia, but not near work time, near work diopter time, outdoor activity time or attending tutoring classes, was associated with myopia incidence and progression in the present population. Using baseline SE could be a simple and effective indicator for myopia prediction.Conclusions and RelevanceIncidence and progression of myopia is relatively high in schoolchildren in Shanghai compared with children of Western countries, East Asia and other parts of China. Effective strategies to control myopia prevalence are in urgent need.

Axial length elongation in primary school-age children: a 3-year cohort study in Shanghai

“…Average eye growth was 0.30 mm/year in children aged 7–9 years from Singapore 17. However, in Baoshan District, another district of Shanghai, AL elongation was 0.38 mm/year 18. In addition, several studies found that AL elongated slowly in European countries.…”

Six-Year Trends on Prevalence of Myopia among School Children in Liuyang, Central South China: Screening Data from 2013 to 2018

“…Mean with standard deviations (SD), and frequencies with percentages were reported in the descriptive statistical analyses for the continuous variables and the categorical variables, respectively. The data from the left eye was used for the estimation of myopia prevalence as a highly signi cant correlation of 0.89 (p>0.001) (Appendix 3) between the left and right eyes was reported 15 .…”

Annual Myopia Progression and Subsequent 2-Year Myopia Progression in Singaporean Children

“…Multiple linear regression analysis was performed, with subsequent 2-year myopia progression as the dependent variable and year 1 myopia progression as the main exposure, with adjustment of the potentially most prognostic covariates: age, gender, ethnicity, maternal education, parental myopia, baseline SE, near work, and outdoor time, all chosen because of their known relationship to the progression of myopia. [16][17][18][19][20] We also defined a binary outcome for predicting future fast myopia progression (based on the median cutoff).…”

“…16 Several longitudinal studies have identified various risk factors for subsequent myopia progression, such as younger age at baseline, greater myopic baseline spherical equivalent (SE), parental myopia, and age of myopia onset. [16][17][18][19][20][21] Being able to estimate faster future myopia progression is important for clinicians seeking to identify an appropriate strategy to control myopia progression. A survey of pediatric ophthalmologists reported that the most common indication for initiating myopia control treatment was prior rate of progression.…”