This study evaluated the efficacy and safety of low-concentration (0.05%, 0.025% and 0.01%) atropine eye drops compared with placebo over a 1-year period.
Study design
The authors conducted a randomized, placebo-controlled, double-masked trial of 438 children (ages 4 to 12 years) with myopia of at least −1.0 D and astigmatism of −2.5 D or less. Participants were randomly assigned in a 1:1:1:1 ratio to receive 0.05%, 0.025% or 0.01% atropine eye drops, or a placebo eye drop, respectively, once nightly to both eyes for 1 year. Cycloplegic refraction, axial length (AL), accommodation amplitude, pupil diameter and BCVA were measured at baseline, 2 weeks, 4 months, 8 months and 12 months. The Visual Function Questionnaire was administered at the 1-year follow-up visit.
Outcomes
After 1 year, the mean change in spherical equivalent (SE) was −0.27 D, −0.46 D, −0.59 D and −0.81 D in the 0.05%, 0.025% and 0.01% atropine groups, and placebo groups, respectively (all P<0.001). The respective mean increase in AL was 0.20 mm, 0.29 mm, 0.36 mm and 0.41 mm (all P<0.001). The accommodation amplitude was reduced by 1.98 D, 1.61 D, 0.26 D and 0.32 D, respectively (all P<0.001).
The pupil sizes under photopic and mesopic conditions were increased respectively by 1.03 mm and 0.58 mm in the 0.05% atropine group, 0.76 mm and 0.43 mm in the 0.025% atropine group, 0.49 mm and 0.23 mm in the 0.01% atropine group, and 0.13 mm and 0.02 mm in the placebo group (all P<0.001). Visual acuity and vision-related quality of life were not affected.
Limitations
This study was conducted in Hong Kong; differences in cause of myopia may vary by ethnicity. Therefore, the findings may not be generalizable to other populations.
Clinical significance
The 0.05%, 0.025% and 0.01% atropine eye drops reduced myopia progression along a concentration-dependent response. All concentrations were well tolerated without an adverse effect on vision-related quality of life. Of the 3 concentrations used, 0.05% atropine was most effective in controlling SE progression and AL elongation over a period of 1 year.