A recent randomized controlled trial conducted by the Pediatric Eye Disease Investigator Group (PEDIG) and funded by the National Eye Institute (NEI) has found that low-dose atropine eyedrops, at a concentration of 0.01%, were no more effective than a placebo in slowing the progression of myopia (nearsightedness) and elongation of the eye in children over a two-year period.
The trial aimed to find an effective method to manage myopia, which is a leading cause of refractive error and can result in irreversible vision loss later in life. The results of the trial were published in JAMA Ophthalmology. Interestingly, these findings contradict the results of recent trials, primarily conducted in East Asia, which showed a benefit from using 0.01% atropine in slowing myopia progression. This inconsistency indicates the need for further research to better understand the optimal use of low-dose atropine in different populations.
Dr. Michael F. Chiang, director of the NEI, emphasized the importance of additional research to explore the potential effectiveness of different doses of atropine in a US population. He also suggested investigating the synergistic effects of combining atropine with other strategies or developing alternative approaches based on a deeper understanding of the underlying causes of myopia progression.
The urgency to identify effective methods for preventing high myopia is driven by the increasing prevalence of myopia worldwide. By 2030, it is predicted that 39 million people in the US will have myopia, and by 2050, this number is expected to reach 44 million in the US and affect 50% of the global population.
Traditionally, higher concentrations of atropine eyedrops (0.5-1.0%) have been used by pediatric eye doctors to slow myopia progression. However, these doses can cause light sensitivity and blurry near vision while the drops are being used. Consequently, there is interest in evaluating lower concentrations of atropine that have been shown to have fewer side effects through clinical studies.
Dr. Michael X. Repka, the lead co-author of the study, noted that the absence of a treatment benefit in their US-based study compared to East Asian studies may be attributed to racial differences in atropine response. The study included fewer Asian children, whose myopia progresses more rapidly, as well as Black children, whose myopia progresses at a slower rate compared to other racial groups.
The study enrolled 187 children between the ages of 5 and 12 years with low-to-moderate bilateral myopia. They were randomly assigned to use nightly atropine (0.01%) or placebo eyedrops for two years. The participants, their parents, and the eye care providers were unaware of the group assignments. The study was conducted at 12 centers throughout the US.
After the two-year treatment period and a six-month follow-up, there were no significant differences between the atropine and placebo groups in terms of changes in the degree of myopia or axial length compared to baseline measurements.
Dr. Katherine K. Weise, the other lead co-author of the study, suggested that a different concentration of atropine may be required for US children to experience a benefit. She also proposed that clinical researchers should evaluate new pharmaceuticals and explore the combination of optical strategies, such as specialized glasses or contact lenses, with other interventions, such as specific wavelengths of light, to determine their effectiveness in reducing the progression of myopia.
It is worth noting that around half of children will experience stabilization of myopia around the age of 16, with a growing percentage stabilizing as they get older. However, approximately 10% of individuals with myopia will continue to become more nearsighted into their early twenties, and this percentage drops to 4% by the age of 24.
Dr. Weise highlighted the importance of vision scientists in unraveling the mysteries of myopia, including understanding the differences in myopic eyes among various races and ethnicities. She emphasized the need for a comprehensive approach to eye research that addresses the environmental, genetic, and structural factors contributing to myopia. a
