Results of the LAMP2 trial indicate a delay of myopia onset and progression, rather than prevention, with 0.05% atropine eyedrop use, leading study investigators to call for further research.
New research investigated the effect of low-concentration atropine eyedrops at 0.05% and 0.01% concentration versus placebo on delaying the onset of myopia in children aged 4 through 9 years.
Study results from the Low-Concentration Atropine for Myopia Prevention (LAMP2) trial indicate nightly use of 0.05% atropine eyedrops resulted in a significantly lower incidence of myopia at 2 years, while 0.01% atropine showed no significant difference versus placebo.1
“Of note, the results in this study could not be interpreted as prevention or decreasing future risk of myopia, because the study duration was only 2 years,” wrote investigators.1 “Furthermore, results of this study suggested a delay of myopia onset and progression, rather than prevention. Nevertheless, this study provides evidence for atropine as an additional strategy for delaying myopia onset beyond increasing time spent outdoors.”
Earlier onset of myopia development has a greater likelihood of high myopia occurring later in life and the condition is irreversible once it has developed. Lifestyle modifications are indicated to delay the onset of myopia, including encouraging children to spend more time outdoors. However, additional strategies have merit, particularly for children at high risk of myopia development.
Countries in Asia have widely adopted low-concentration atropine eyedrops in reducing myopia progression, but it is unknown whether atropine treatment is effective in the delay of myopia onset. The LAMP2 trial assessed the efficacy of low-concentration atropine in delaying myopia onset in children at the Chinese University of Hong Kong Eye Centre. Investigators, led by Jason C. Yam, MPH, recruited participants beginning treatment in July 2017 with the last participant enrolled in June 2020. The final follow-up session occurred in June 2022.
Children were required to have cycloplegic spherical equivalent between +1.00 and 0.00 D, astigmatism of less than -1.00 D, anisometropia of less than 2.00 D, and at least 1 parent whose spherical equivalent showed more myopia than −3.00 D. All enrolled children were randomized in a 1:1:1 ratio to receive 0.05% atropine, 0.01% atropine, or placebo eyedrops once nightly in both eyes at their baseline visit.
Investigators followed up with participants at the same schedule at 2 weeks after baseline for monitoring and up to 24 months after baseline. The study’s defined primary outcomes were the cumulative incidence rate of myopia (cycloplegic spherical equivalent of at least −0.50 D in either eye) and the percentage of participants with fast myopic shift (spherical equivalent myopic shift of at least 1.00 D).
Out of 474 randomized participants (mean age, 6.8 years; 50% female), 353 (74.5%) completed the trial after 121 participants dropped out during the 2-year follow-up period. Results indicate the 2-year cumulative incidence rates of myopia for study participants were 28.4% (33 of 116) in the 0.05% atropine group, 45.9% (56 of 122) in the 0.01% atropine group, and 53.0% (61 of 115) for the placebo group. The percentages of fast myopic shift at 2 years for these groups were 25.0%, 45.1%, and 53.9%, respectively.
When compared with placebo, it was shown that the 0.05% atropine group had significantly lower 2-year cumulative myopia incidence (difference, 24.6%; 95% confidence interval [CI], 12.0% - 36.4%) and percentage of patients with fast myopic shift (difference, 28.9%; 95% CI, 16.5% - 40.5%). Then, compared with the 0.01% atropine group, 0.05% atropine had significantly lower 2-year cumulative myopia incidence (difference, 17.5%; 95% CI, 5.2% - 29.2%) and percentage of patients with fast myopic shift (difference, 20.1%; 95% CI, 8.0% - 31.6%).
Investigators noted there was no significant difference between the 0.01% atropine and placebo groups at 2 years in myopia incidence or the percentage of patients with fast myopic shift.
“This result suggests that the concentration of 0.01% atropine might not be strong enough to achieve sufficient treatment effects,” added investigators.1