The influence of age in the progression from pre-myopia to myopia onset: a 1 year retrospective analysis.
Younger children show faster eye elongation when progressing from pre-myopia to myopia.
The influence of age in the progression from pre-myopia to myopia onset: a 1 year retrospective analysis.
Pre-myopia is a critical stage before myopia onset, yet little is known about how age influences axial elongation during the transition from pre-myopia to myopia.
This study aimed to investigate the effect of age on annual axial elongation during this 1 year conversion period.
This retrospective study included 53 children (53 right eyes) aged 6-10 years who progressed from pre-myopia (spherical equivalent refraction ≤ + 0.75 D and > - 0.50 D) to myopia (≤ - 0.50 D) within 1 year.
younger children's eyes lengthen faster each year than older children's
Annual axial elongation decreased with increasing age: 0.76 ± 0.16 mm (6y), 0.64 ± 0.17 mm (7y), 0.54 ± 0.24 mm (8y), 0.37 ± 0.14 mm (9y), and 0.38 ± 0.03 mm (10y).
After adjusting for baseline ocular biometrics, analysis of covariance revealed a significant main effect of age on ΔAL [ F (3, 45) = 3.689, p = 0.019, partial η 2 = 0.197].
Bonferroni-corrected comparisons showed that children aged 6 and 7 years exhibited significantly greater axial elongation than those aged 9 years (mean differences = 0.391 mm and 0.271 mm, respectively; both p < 0.01).
Among children who converted from pre-myopia to myopia within 1 year, younger age was associated with greater axial elongation.
These findings highlight the importance of early surveillance and preventive strategies in the pre-myopic stage, particularly for children aged 6-7 years.
Larger prospective studies controlling for environmental and familial risk factors are needed.