Timing of height growth peaks and axial elongation in atropine-treated myopic children

PURPOSE: To investigate the association between systemic height growth rate and ocular axial elongation rate in atropine-treated children with myopia, and to explore whether the timing of height growth provides clinically relevant information regarding periods of axial elongation during treatment. METHODS: Children with myopia (< 15 years) who underwent serial ocular biometry and anthropometric measurements over ≥ 3 visits spanning > 1 year were included. Participants were classified into a control group (no atropine) and an atropine group (0.05% nightly, initiated for axial elongation ≥ 0.4 mm/year). Axial elongation and height growth rates were calculated for each inter-visit interval. Peak growth ages were defined as those with the greatest inter-visit changes. Subgroup analyses in the atropine group were based on the median peak height growth age (10.45 years) and median annual axial elongation rate (0.21 mm/year). RESULTS: A total of 139 eyes from 70 children were analyzed (56 control, 83 atropine-treated). Height growth rate and axial elongation rate were not significantly correlated in either group. In the control group, peak height growth age and peak axial elongation age showed similar unimodal distributions. In the atropine group, however, the distribution of peak height growth age showed a broadened pattern with marginal deviation from unimodality (P = 0.051) and associated strongly with peak axial elongation age (β = 0.91, P < 0.01). Children with earlier height growth peaks had greater annual axial elongation (0.27 ± 0.17 vs. 0.15 ± 0.12 mm/year; P < 0.01) despite identical dosing. CONCLUSIONS: Among atropine-treated children, earlier systemic growth peaks were associated with faster axial elongation. Monitoring height growth timing may help identify rapid ocular growth periods and optimize treatment strategies.