1.Refractive progression among students aged 4-14 in Shanghai and associated factors
XIANG Kaidi, WANG Jingjing, PAN Chenwei, CHEN Jun, QI Ziyi, ZOU Haidong, XU Xun, HE Xiangui
Chinese Journal of School Health 2022;43(9):1309-1313
Objective:
To investigate the refractive progression and associated factors of children of different ages and refractive status, and to provide guidance on myopia prevention and control program formulation and work practice.
Methods:
A total of 20 kindergartens, primary schools, and secondary schools in 2 districts of Shanghai were selected based on the existing cohort, and baseline data in 2015 and one year follow up data in 2016 were collected from 1 510 children aged 4 to 14, including cycloplegic spherical equivalent refraction (SER), axial length (AL), and corneal curvature. The distribution and progression of SER and AL in children of different ages and refractive status were analyzed, and the influencing factors of SER progression (ΔSER) were explored using multiple linear regression.
Results:
ΔSER remained relatively stable at age 4 and 5 (average -0.08 to -0.07 D/year), and SER drifted significantly towards myopia (average -0.50 to -0.31 D/year) in all groups older than 6 years, dropping back to -0.44 to -0.33 D/year after age 11; Elongation of AL (ΔAL) was 0.27 to 0.35 mm/year in 4 to 10 years group, and decreased to 0.15 to 0.22 mm/year in 11 to 14 years group. The ΔSER and ΔAL were greatest in the new onset myopes [(-0.90± 0.05 )D, (0.51±0.02)mm], followed by the low myopia group [(-0.68±0.04)D, (0.36±0.02)mm], then followed by the moderate to high myopia group[(-0.49±0.06)D,(0.23±0.03)mm] and the lowest in the hyperopia group[(-0.21±0.02)D, ( 0.26 ±0.01)mm], with a statistically significant difference among these groups ( P <0.05). Age ( β =-0.07), baseline SER ( β = 0.05 ) and ΔAL ( β =-0.78) were independent influencing factors for refractive progression in the 4 to 10 years old group, while ΔAL( β =-1.55) was the only independent influencing factor in the 11 to 14 years old group ( P <0.05).
Conclusion
The elongation of AL in preschoolers is mostly physiologically and should be prevented from growing beyond the physiological range by increasing outdoor activities. The primary students, as well as students with pre myopia or low myopia are the priority groups for dynamic monitoring and intervention in myopia prevention and control.