Premyopia Progression and Low-Dose Atropine Intervention in Children with Unilateral Myopia

To compare refractive progression between myopic and premyopic eyes within the same children and evaluate the potential role of low-dose atropine on premyopia progression.

This 12-month randomized controlled trial enrolled children aged 4-12 years with one myopic and one premyopic eye. Participants were assigned to three groups: no atropine intervention (NI), 0.01% atropine in myopic eye (MI), or bilateral intervention (BI). Spherical equivalent (SE) and axial length (AL) were measured at 3-month intervals. Linear mixed-effects models included all randomized participants, while generalized estimating equations with multiple imputation and Cox regression assessed myopic shift (ΔSE ≤ -0.50 D/year) and myopia onset.

Ninety-five of 104 children completed the study. In the NI group, myopic eyes showed greater progression than premyopic eyes, with adjusted interocular differences of -0.19 D (95% CI, -0.32 to -0.05; p = 0.007) in SE change and 0.08 mm (95% CI, 0.03 to 0.12; p = 0.001) in AL change. In premyopic eyes, BI showed 0.21 D less SE progression (p = 0.046) and 0.14 mm less AL elongation (p = 0.016) than MI, but neither differed significantly from NI. Myopic shift risk was lower in BI than MI (RR, 0.52; 95% CI, 0.27 to 0.99) and NI (RR, 0.50; 95% CI, 0.26 to 0.97). Atropine intervention (HR, 0.50; p = 0.037) and higher baseline SE (HR, 0.06; p < 0.001) were associated with a lower hazard of myopia onset.

Untreated myopic eyes showed greater SE progression and AL elongation than their fellow premyopic eyes. 0.01% atropine treatment showed a potential effect in reducing myopic shift and incidence. Meanwhile, the management should be individualized according to baseline refraction and documented progression.