Predictive value of early treatment response for long-term outcomes after seven years on low-dose atropine.

BACKGROUND/AIMS: To determine whether first-year response to low-dose atropine predicts long-term myopia control and may guide treatment escalation in myopic children. METHODS: A retrospective chart review (2012-2025) identified children treated with atropine 0.01%-0.05% at a single practice with ≥54 months of treatment. Children were excluded with insufficient follow-up (<54 months of treatment), comorbidities that might affect myopia progression or concurrent baseline optical myopia-control therapy. First-year response was modelled as the spherical equivalent refraction (SER) progression rate (diopters (D)/year, continuous, positive values indicating worsening myopia) and by responder status (defined as≤0.25D total progression at 12±3 months). The primary outcome was successful control maintaining≤0.25 D/year over follow-up. Key secondary outcomes were total SER progression and time-to-treatment escalation. Eye-level models accounted for correlation between fellow eyes and adjusted for baseline age and baseline SER. RESULTS: 71 children (142 eyes) had a mean follow-up of 6.8±2.0 years. First-year responders included 101/142 eyes (71%) with higher odds of successful control (adjusted OR 2.66, 95% CI 1.11 to 6.35, p=0.028) and less total SER progression (adjusted difference 0.57D, 95% CI 0.28 to 0.86, p<0.001). Each additional 0.25 D/year of year-1 progression was associated with lower odds of successful control (OR 0.73, 95% CI 0.59 to 0.89, p=0.002) and greater total progression (0.22 D more, 95% CI 0.16 to 0.29, p<0.001). Dose escalation occurred earlier in nonresponders; responders had a lower hazard of escalation (HR 0.27, 95% CI 0.14 to 0.52). CONCLUSION: First-year SER change is strongly predictive of long-term outcomes; despite earlier treatment escalation in nonresponders, responders had a much higher likelihood of sustained long-term control. Early response assessment may help identify high-risk patients for closer monitoring and/or treatment intensification.