Impact of coronavirus disease 2019 restrictions on the efficacy of atropine 0.01% eyedrops for myopia control – Findings from the Western Australia Atropine for the Treatment of Myopia study

Abstract This study explored the impact of short-term coronavirus disease 2019 (COVID-19) restrictions on the efficacy of atropine 0.01% eyedrops on myopia control in a multiethnic cohort of Australian children. In the Western Australia Atropine for the Treatment of Myopia study, 104 and 49 children were randomized to receive atropine 0.01% eyedrops and a placebo, respectively. We compared the 1-year myopia progression and axial elongation following the 2-month lockdown in 2020 to the same months in 2019 and 2021, i.e., the 1-year myopia progression up to May 2019–October 2019 (non-COVID-19) versus the 1-year progression up to May 2020–October 2020 (COVID-19 period), and the 1-year progression up to May 2021–October 2021 (non-COVID-19) versus the 1-year progression up to the same months in 2020. After excluding participants who withdrew, completed their treatment phase prior May 2020, or those whose study visits did not fall between May 2020 and October 2020, 65 participants (mean age at baseline = 11.8 ± 2.5 years) were included in the final analysis (49 in the treatment group; 16 in the placebo group). After correcting for age, sex, and ethnicity, there was no significant main effect of the short-term lockdown on the rate of spherical equivalent or axial length change. However, there was a lockdown × treatment interaction effect on the rate of axial elongation ( P = 0.007). This was such that in the treatment group, the 1-year axial elongation was faster during lockdown by 0.056 mm compared to the nonlockdown periods ( P = 0.009), while the rate of axial elongation in those on the placebo eye drops was similar during lockdown and nonlockdown. Our findings suggest that there is a decreased efficacy of low-concentration atropine even with relatively lenient restrictions lasting for a few months.