Atropine treatment for myopia in western countries – rationale
Reviewed by Ivan Yip

This preliminary study sets out the rationale, methodology and participant baseline characteristics for the Western Australia Atropine for the Treatment of Myopia (WA-ATOM). It is a double masked randomised placebo-controlled trial. This study is designed to be combined with the Myopia Outcome Study of Atropine in Children (MOSAIC) study in Ireland and the Children Atropine for Myopia Progression (CHAMP-UK) study. The ATOM 1 and 2 landmark studies in Singapore surprisingly showed a concentration of 0.001% atropine slowed myopia to -0.72D and +0.58mm axial length increase from baseline. Higher doses showed significant rebound effect. The LAMP study carried out in Hong Kong found 0.05% atropine to be optimal. These existing studies, however, are carried out in mainly Asian populations and there lacks a control group. The authors of these newer studies postulate atropine management of myopia may differ in Caucasian children and other ethnicities due to different colour iris, possible slower rate of myopia progression and an increased time spent outside. One hundred and fifty-three children have been enrolled and randomised as of 2017. Children are selected between 6-16 years, cycloplegic spherical equivalent of -1.50D, myopia progression over 12 months previously, and best corrected visual acuity (BCVA) 0.2logMAR (6/9 Snellen). For the first three years children are randomly assigned to the control or treatment arm (1:2). There is then a one-year washout period and participants are unmasked and discharged. Patients are still followed up for another two years and in these two years can decide on their own myopia treatment. Treatment of myopia is a pressing issue around the world. This preliminary study highlights the rationale for the upcoming studies carried out in non-Asian countries. It also discusses possible mechanisms of action of atropine in the prevention of myopia.

Western Australia Atropine for the Treatment of Myopia (WA-ATOM) study: Rationale, methodology and participant baseline characteristics.
Lee SSY, Mackey DA, Lingham G, et al.
CLINICAL & EXPERIMENTAL OPHTHALMOLOGY
2020;48(5):569-79.