Atropine Concentration Affects Efficacy, Safety Profile in Pediatric Myopia

Atropine concentration has a dose-dependent effect on slowing myopia progression in pediatric patients, according to a study published in Journal Français D’Ophtalmologie. While higher doses demonstrate better myopia control efficacy, lower doses show a better safety profile, according to the report.

Researchers performed a meta-analysis of 18 randomized controlled trials conducted before October 14, 2001. The team examined efficacy outcomes, which included spherical equivalent (SE) progression and axial length (AL) elongation, and safety outcomes, which included accommodation amplitude, pupil size, and adverse effects. Among the studies included in the analysis, 17 contained SE data, 16 examined AL, 3 explored accommodation amplitude, 2 examined pupil size, and 10 had data regarding adverse effects.

Atropine slowed myopia progression in children after 6 to 36 months, and higher atropine concentrations resulted in higher weighted mean differences (WMD) compared with no atropine treatment, according to the report. Compared with control group participants, WMDs for SE and AL were 0.25 diopters (D) and 0.1 mm, 0.44 D and 0.16 mm, and 1.21 D and 0.82 mm for low-dose, moderate-dose, and high-dose atropine, respectively. The trend of greater WMDs for higher atropine doses continued at 24 months, the report shows.

There were no significant differences in accommodation amplitude, photopic pupil size, the rate of photophobia, allergy, or blurred vision between individuals treated with low atropine concentration compared with control group participants. High-dose atropine, however, increased the risk of photophobia (risk ratio [RR], 12.46; 95% CI, 2.09-74.21), allergy (RR, 19; 95% CI, 1.11-324.25), blurred vision (RR, 10.18; 95%CI, 1.28-80.82), and other adverse events (RR, 13.72; 95% CI, 1.81-104.27).  

“Atropine in different concentrations can effectively slow myopia progression in children, and its effect is dose-dependent,” according to the researchers. “Considering the adverse effects, low-dose atropine (0.01% atropine) appears to be safer. More evidence on low-dose atropine is needed, there is a current lack of guidance on timing of therapy initiation, duration of therapy, and the period needed for tapering off the medication without causing a rebound effect.

Study limitations include potential publication bias to the strict inclusion of trials written in English, an overrepresentation of children of Chinese ethnicity, which may limit generalizability, and the limited number of trials included in the assessment.