0.01% atropine eye drops and axial elongation in pre-myopic children: a real-world study

Purpose This study aimed to evaluate the association between 0.01% atropine use and axial length (AL) elongation, as well as refractive change, in pre-myopic children using real-world clinical data. Methods In this retrospective analysis, pre-myopic children aged 6–12 years (by non-cycloplegic subjective refraction) were included. After 1:2 propensity score matching (PSM), 176 children treated with nightly 0.01% atropine were compared with 352 untreated controls ( N = 528). All participants had approximately 6 months of follow-up (mean 7–8 months). The primary outcomes were the rates of change in AL and SE, assessed with linear mixed-effects models; myopia incidence (SE ≤ − 0.50 D) was assessed as a secondary outcome using an interval-censored Cox model. A subgroup analysis by baseline AL progression rate (fast: ≥0.08 mm per 3 months vs. slow: <0.08 mm per 3 months) was prespecified as exploratory and was not adjusted for multiple comparisons; effect modification by corneal curvature was assessed with a treatment × time × flat keratometry interaction model. Results The intervention group showed significantly slower AL elongation (between-group difference − 0.021 mm per 3 months, 95% CI − 0.033 to − 0.010, P < 0.001), whereas the difference in SE progression was not statistically significant ( P = 0.069). Myopia incidence did not differ significantly between groups (38.1% vs. 42.6%; hazard ratio 0.89, 95% CI 0.66 to 1.20, P = 0.44). In an exploratory subgroup analysis, the effect appeared larger in the fast-progression subgroup; however, the treatment × time × flat keratometry interaction was not significant for AL ( P = 0.109). Conclusions Use of 0.01% atropine was associated with modestly slower axial elongation in pre-myopic children. An exploratory subgroup analysis suggested a possibly greater effect in children with rapid baseline axial elongation, but these findings require prospective confirmation. Registration ChiCTR2500114828 (retrospective observational study registered December 17, 2025).