Efficacy of atropine eyedrops in reducing myopia progression and axial elongation in myopic children: a meta-analysis

Purpose: To determine the efficacy of various concentrations of atropine eyedrops on retarding myopia progression and axial elongation in Asian children. Study design: Meta-analysis. Methods: Randomized clinical trials and prospective interventional non-randomized studies which enrolled children aged 4 to 14 years old who received atropine treatment for myopia were included in the study. The Cochrane Collaboration 6 aspects of bias was used to assess the risk of bias for all included studies. Outcome measures were myopia progression and axial elongation. Meta-analysis was conducted using the random-effects model. Results: Eight randomized clinical trials and two prospective interventional non-randomized studies which included a total of 1,229 Asian children were included in the analysis. The pooled mean difference between control and atropine for myopia progression was 0.77 diopters (D) per year [CI 0.64, 0.89]. Subgroup analysis by concentration showed a decreasing trend with decreasing concentration. The pooled mean difference of myopia progression for 1%, 0.5%, 0.25%, and 0.1–0.125% atropine was 0.97 D/year [CI 0.72, 1.21], 0.88 D/year [CI 0.74, 1.02], 0.79 D/year [CI 0.37, 1.21], and 0.80 D/year [CI 0.62, 0.97], respectively; whereas that for 0.01% atropine was 0.46 D/year [CI -0.02, 0.94] indicating that this intervention may or may not be favorable for slowing myopia progression. The pooled mean difference between control and atropine for axial elongation was -0.22 mm [CI -0.29, -0.14] favoring atropine. Subgroup analysis by concentration also showed decreasing trend with decreasing concentration. The pooled mean difference of axial elongation for 1%, 0.5%, 0.1%, 0.05%, and 0.025% atropine was -0.44 mm [CI -0.57, -0.32], -0.19 mm [CI -0.35, -0.04], -0.10 mm [CI -0.17, -0.03], -0.21 mm [CI -0.28, -0.14], and -0.12 mm [CI -0.16, -0.08], respectively; whereas that for 0.01% atropine was -0.01 mm [CI -0.09, 0.06] indicating that this intervention may or may not be favorable in reducing axial elongation. Conclusion: This meta-analysis shows that the effects of atropine for both myopia progression and axial elongation are dose-dependent for the concentration 0.025% to 1%. Results for 0.01% atropine are still equivocal.