Topical Atropine for Childhood Myopia Control: The Atropine Treatment Long-Term Assessment Study

IMPORTANCE: Clinical trial results of topical atropine eye drops for childhood myopia control have shown inconsistent outcomes across short-term studies, with little long-term safety or other outcomes reported. OBJECTIVE: To report the long-term safety and outcomes of topical atropine for childhood myopia control. DESIGN, SETTING, AND PARTICIPANTS: This prospective, double-masked observational study of the Atropine for the Treatment of Myopia (ATOM) 1 and ATOM2 randomized clinical trials took place at 2 single centers and included adults reviewed in 2021 through 2022 from the ATOM1 study (atropine 1% vs placebo; 1999 through 2003) and the ATOM2 study (atropine 0.01% vs 0.1% vs 0.5%; 2006 through 2012). MAIN OUTCOME MEASURES: Change in cycloplegic spherical equivalent (SE) with axial length (AL); incidence of ocular complications. RESULTS: Among the original 400 participants in each original cohort, the study team evaluated 71 of 400 ATOM1 adult participants (17.8% of original cohort; study age, mean [SD] 30.5 [1.2] years; 40.6% female) and 158 of 400 ATOM2 adult participants (39.5% of original cohort; study age, mean [SD], 24.5 [1.5] years; 42.9% female) whose baseline characteristics (SE and AL) were representative of the original cohort. In this study, evaluating ATOM1 participants, the mean (SD) SE and AL were −5.20 (2.46) diopters (D), 25.87 (1.23) mm and –6.00 (1.63) D, 25.90 (1.21) mm in the 1% atropine-treated and placebo groups, respectively (difference of SE, 0.80 D; 95% CI, −0.25 to 1.85 D; P = .13; difference of AL, −0.03 mm; 95% CI, −0.65 to 0.58 mm; P = .92). In ATOM2 participants, the mean (SD) SE and AL was −6.40 (2.21) D; 26.25 (1.34) mm; −6.81 (1.92) D, 26.28 (0.99) mm; and −7.19 (2.87) D, 26.31 (1.31) mm in the 0.01%, 0.1%, and 0.5% atropine groups, respectively. There was no difference in the 20-year incidence of cataract/lens opacities, myopic macular degeneration, or parapapillary atrophy (β/γ zone) comparing the 1% atropine-treated group vs the placebo group. CONCLUSIONS AND RELEVANCE: Among approximately one-quarter of the original participants, use of short-term topical atropine eye drops ranging from 0.01% to 1.0% for a duration of 2 to 4 years during childhood was not associated with differences in final refractive errors 10 to 20 years after treatment. There was no increased incidence of treatment or myopia-related ocular complications in the 1% atropine-treated group vs the placebo group. These findings may affect the design of