In a surprising turn of events, a large-scale, long-term study has produced results that contradict the findings of recent trials conducted primarily in East Asia. The study in question investigated the effectiveness of 0.01% atropine in slowing myopia, but the results were inconsistent.
Researchers studied the effectiveness of low-dose atropine eyedrops in slowing the progression of myopia (nearsightedness) in children. They found that using these eyedrops for two years did not slow down the elongation of the eye or improve vision any more than using a placebo. The study was conducted by the Pediatric Eye Disease Investigator Group and funded by the National Eye Institute. The results were published in JAMA Ophthalmology.
This has led experts to question whether a different dose might be more effective for a US population, if combining atropine with other strategies could have a synergistic effect, or if alternative approaches to treatment or prevention could be developed based on a better understanding of what causes myopia progression.
Dr. Michael F. Chiang, M.D., director of the National Eye Institute (NEI), which is part of the National Institutes of Health, emphasizes the importance of finding an optimal approach for preventing high (advanced) myopia. This is particularly urgent given the escalating prevalence of myopia overall and the increased risk of it progressing to high myopia. By 2030, it’s predicted that 39 million people in the U.S. will have myopia. By 2050, that number is expected to grow to 44 million in the U.S. and to 50% of the global population.
A common concern among parents and healthcare professionals alike is the rapid progression of myopia in children. Traditionally, stronger concentrations of atropine eyedrops (0.5-1.0%) have been used to slow myopia progression, but they come with side effects like light sensitivity and blurry near vision. This has led to interest in clinical studies exploring lower concentrations of atropine, which may have fewer side effects.
The study’s lead co-author, Michael X. Repka, M.D., professor of ophthalmology at Johns Hopkins University, believes that the absence of a treatment benefit in the U.S.-based study compared to East Asian studies could be due to racial differences in atropine response. The study enrolled fewer Asian children, whose myopia progresses more quickly, and included Black children, whose myopia progresses less quickly compared to other races.
The study involved 187 children aged 5 to 12 years with low-to-moderate bilateral myopia, who were randomly assigned to use nightly atropine (0.01%) or placebo eyedrops for two years. After the treatment period and six months after treatment stopped, there were no significant differences between the groups in terms of changes in degree of myopia compared to baseline, nor were there significant differences in axial length within the two groups compared to baseline measurements.
Katherine K. Weise, O.D., professor at the University of Alabama at Birmingham, suggests that a different concentration of atropine might be needed for U.S. children to experience a benefit. She also believes that clinical researchers could evaluate new pharmaceuticals and special wavelengths of light in combination with optical strategies, such as special glasses or contact lenses, to reduce the progression of myopia.
Dr. Repka also emphasizes the importance of understanding the differences in myopia progression among different races and ethnicities to create new treatment strategies. He believes that a convergence of eye research will be necessary to solve the environmental, genetic, and structural mystery of myopia.