A Meta-Analysis Assessing Change in Pupillary Diameter, Accommodative Amplitude, and Efficacy of Atropine for Myopia Control.

Abstract

To determine the effect of atropine on pupillary diameter, accommodative amplitude as well as myopia progression. Medical databases and Cochrane Library were systematically searched for studies from 1980 until June 2020. The primary and secondary outcomes were: a) change in pupillary diameter (PD) and accommodative amplitude (AA) and b) annualized mean change in spherical equivalent and axial length with various concentrations of atropine compared to control. Thirteen trials (6 RCTs, 7 observational studies) that studied 9 atropine concentrations (0.01-1.0%) were included. The relation between atropine and change in PD and AA was nonlinear; at < 0.10% atropine, the slope of the curve was steep but the change in PD (+0.7 mm; 95% CI: +0.1 to +1.4) and AA (-1.6D; 95% CI: -3.9 to +0.7) was smaller whereas at ≥0.10% atropine, the slope plateaued but change in PD (+3.2 mm, 95% CI: +2.8 to +3.5) and AA (-10.7D; 95% CI: -12.2 to -9.2) was high.Reduction in myopia progression with atropine at <0.10% and ≥0.10% as compared to controls was 0.37D (95% CI: 0.16 to 0.58) versus 0.75D (95% CI: 0.17 to 1.33) for spherical equivalent and -0.10 mm (95% CI: -0.24 to 0.05) versus -0.23 mm (95% CI: -0.34 to -0.13) for axial length. A nonlinear dose-response relationship exists between atropine and PD and AA. Further work is warranted to determine the concentration that provides maximal efficacy with tolerable side effects.