This recent randomized clinical trial examined the efficacy and safety of 0.01% atropine eye drops in children with myopia of −0.50 to −6.00 diopters and basic-type intermittent exotropia. The study addresses the limited evidence on atropine interventions for this specific cohort.
Myopia and exotropia are often concomitant and are considered mutual risk factors for each other, the researchers explain in the study published in JAMA Ophthalmology. “A cross-sectional study of children aged 6 to 72 months in the Multi-Ethnic Pediatric Eye Disease Study in southern California and the Baltimore Pediatric Eye Disease Study in Maryland revealed a higher prevalence rate of myopia in children with exotropia (12.7%) than in children without exotropia (4.6%)," the researchers state in the study. They continue to explain that, "more than 90% of patients with intermittent exotropia (IXT) would develop myopia by 20 years of age, which was higher than that in populations without strabismus.” The researchers further describe that it is thought that “myopia is associated with a decreased demand for accommodation and, hence, lower convergence and a predisposition for developing exotropia.”
The double-masked, placebo-controlled trial included 300 children from 6 to 12 years old with IXT and myopia. Participants were randomly assigned to receive 0.01% atropine or placebo eye drops in a 2:1 ratio for 12 months. The primary outcome measured was the change in cycloplegic spherical equivalent at 1 year. Secondary outcomes included changes in axial length (AL), accommodative amplitude (AA), exotropia conditions, and binocular vision, also at 1 year. Participants were assigned randomly to the 0.01% atropine group (200 children) or to the placebo group (100 children). All participants completed at least one follow-up visit, and both groups had good treatment compliance and the same daily outdoor time.
At 1 year, the atropine group had a significantly slower progression in spherical equivalent and AL elongation compared to the placebo group. The atropine group also showed a decrease in near magnitude of exodeviation compared to the placebo group, which showed an increase. There were no substantial adverse effects on binocular vision or exotropia control.
The incidence of photophobia was 6.0% in the atropine group and 8.0% in the placebo group, while blurred near vision occurred in 6.0% of the atropine group and 7.0% of the placebo group. The researchers found no intraocular pressure or corneal endothelial cell density (ECD) issues, which contrasted with a previous study that suggested atropine-induced time-dependent reduction of ECD. In the JAMA study, “a meta-analysis involving the comparison of ECD change between the orthokeratology plus 0.01% atropine group and the orthokeratology group revealed no difference.”
The researchers concluded, “Although this study supported the use of 0.01% atropine for the first year, it is uncertain whether efficacy and safety will be maintained in the second year…[Nevertheless,] this placebo-controlled, double-masked, randomized clinical trial established that 0.01% atropine eye drops, although compromising AA to some extent, appeared effective and safe in slowing myopia progression without interfering with exotropia conditions or binocular vision in children with myopia and IXT.”
