Low-Dose Atropine Reduces Elongation of Axial Length
Ophthalmology, December 2020
Use of low-concentration atropine eyedrops is intended to slow myopia progression. Li et al. looked at changes in ocular biometrics among patients who received placebo or 0.05%, 0.025%, or 0.01% atropine. They observed antimyopia effects with low-dose atropine, including significant reductions in axial length (AL) elongation. However, no clinical effects on corneal or lens power were noted.
For this double-masked, randomized, placebo-controlled study, 383 children (age, 4 to 12 years) were recruited from the earlier LAMP study. All had myopic refraction of at least –1.0 D in both eyes and astigmatism of less than 2.5 D. Atropine or placebo was administered to both eyes once a day. Participants were assigned randomly to one of the four study groups. Lens power was calculated using measurements from both eyes, including cycloplegic spherical equivalent (SE), AL, corneal curvature (K), and anterior chamber depth (ACD).
The degree of response was found to be concentration dependent. Throughout the year, the changes in AL were 0.20 ± 0.25 mm, 0.29 ± 0.20 mm, 0.36 ± 0.29 mm, and 0.41 ± 0.22 mm with 0.05% atropine, 0.025% atropine, 0.01% atropine, and placebo, respectively (p < .001). The average K remained stable with all dosages of atropine. Although corneal astigmatism worsened in all atropine groups, the degree of change was similar for the three concentrations. Lens power declined over time and ACD deepened in each group, with no discernible differences between concentrations. AL elongation was the greatest contributing factor to myopia progression, accounting for more than 70% of the progression. Contributions to SE progression from ocular biometric changes, adjusted for age and gender, were statistically similar for the four groups.
These findings suggest that low-dose atropine exerts antimyopia effects mainly by delaying AL elongation, which potentially could decrease the risk of subsequent myopia complications.
The original article can be found here.