Tag: myopia

No Cure for Myopia Progression in Sight as Eyedrops Trial Flops

Photo by CDC on Unsplash

A US study shows that use of low-dose atropine eyedrops, commonly used in a higher dose to treat lazy eye, was no better than a placebo at slowing myopia progression and elongation of the eye among children treated for two years.

The first randomised controlled trial of its kind aimed at identifying an effective way to manage myopia was published last week in JAMA Ophthalmology. It was conducted by the Pediatric Eye Disease Investigator Group at at Vanderbilt University Medical Center (VUMC) and 11 other hospitals and practices across the United States and funded by the National Eye Institute (NEI).

“We found, interestingly, and honestly shockingly, that there was no difference in the use of 0.01% atropine and placebo in treating these children who ranged in age from 5 to 12,” said associate professor Lori Ann Kehler, OD, and the Vanderbilt site principal investigator for the study.

The onset of myopia usually occurs between the ages of 7 and 16 when developing eyes can start growing too long axially (from front to back). Instead of focusing images on the retina, images of distant objects are focused at a point in front of the retina which causes people to have poor distance vision while their near vision remains unchanged.

The condition results in the need for eyeglasses to improve distance vision, and it can also result in medical complications and serious uncorrectable vision loss later in life, like retinal detachments or myopic macular degeneration.

The study contradicts earlier studies from East Asia that showed the small dose of atropine is effective in slowing progression of myopia.

In 2017 the Academy of Ophthalmology endorsed the findings from East Asia saying that although the FDA had not approved atropine for this use, there was sufficient evidence for prescribing the low dose for myopia. Ophthalmologists across the country, including at VUMC, began to offer the prescription to young patients with myopia.

“That was a really exciting finding at the time because we had had no treatment options for many years,” Kehler said. The prescription of atropine for treating myopia is not covered by most insurance plans.

“The incidence of myopia is increasing worldwide,” Kehler said. “By 2030 it’s predicted that 39 million people in the US will have myopia. By 2050 that number is expected to increase to more than 44 million people in the US and to 50% of the global population. Once it’s detected in children, it tends to get worse every year,” she said. “Investigators all over the world have tried strategies to intervene, to either stop or slow the worsening of myopia.”

Kehler said it is not known why the incidence of myopia is increasing. “There are several theories. Some believe it’s the increase in the use of screens and screen time, but myopia was increasing even before screens were part of children’s lives. Others think it has to do with industrialisation. We were an agricultural society. We were outside more. We weren’t reading. We weren’t looking up close all day. Really, the prevailing thought is whether we’re at a screen or looking at a math book or reading most of the day, we think the lack of sunlight and sustained near effort is what’s causing the increase of myopia.”

Kehler said the percentage of children with myopia using the atropine drop at VUMC is low and estimates fewer than 5% of children with myopia are using the drops nationally.

Going forward, eye specialists should have a frank discussion with parents of children with myopia about the conflicting data between the Asian studies and the new U.S. study.

“The absence of a treatment benefit in our US-based study, compared to East Asian studies, may reflect 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 with other races,” noted the study’s lead co-author, Michael X. Repka, MD, professor of Ophthalmology at Johns Hopkins University, in a news release from the NEI.

“All the studies have shown the drops are safe, so we aren’t putting children at risk if we continue to prescribe the 0.01%,” Kehler said. “But we are telling them there is a difference in these studies and it might have to do with your genetics; it might be that it’s more effective in children from Asia than in the U.S. population,” she said.

Further study is needed, Kehler said. The next step is likely to study a higher dose of atropine to see if children in the U.S. experience a benefit.

The LAMP study out of Hong Kong found that 0.05% might be more effective.

Kehler said other groups are studying the use of red-light therapy to slow the progression of myopia, and there are also new eyeglass lenses that have been developed to slow the progression of myopia, but they are not yet available in the U.S.

“It’s much harder to get drops in very young children,” Kehler said. “But if we had a spectacle option, that would open the door to treating our younger patients.”

Myopia usually stabilises in about half of children around 16 years of age and among an increasingly larger percentage as they get older. By their early 20s, about 10% of individuals with myopia will continue to grow more nearsighted, and by age 24 that percentage is 4%.

Source: Vanderbilt University Medical Center

Atropine Eyedrops Fail to Slow Myopia Progression in US Children

Photo by Jeffrey Riley on Unsplash

Use of low-dose atropine eyedrops (concentration 0.01%) was no better than placebo at slowing myopia progression and elongation of the eye among children treated for two years, according to a randomised controlled trial conducted in the US. The trial aimed to identify an effective way to manage this leading and increasingly common cause of refractive error, which can cause serious uncorrectable vision loss later in life. Results from the trial, published in JAMA Ophthalmology, contradict those from recent trials in East Asia.

The study was conducted by the Pediatric Eye Disease Investigator Group (PEDIG) and funded by the National Eye Institute (NEI).

“The overall mixed results on low-dose atropine show us we need more research. Would a different dose be more effective in a US population? Would combining atropine with other strategies have a synergistic effect? Could we develop other approaches to treatment or prevention based on a better understanding of what causes myopia progression?” said Michael F. Chiang, MD, director of the NEI, which is part of the National Institutes of Health.

Identifying an optimal approach for preventing high (advanced) myopia is urgently needed given the escalating prevalence of myopia overall and the 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.

Much stronger concentrations of atropine eyedrops (0.5-1.0%) have long been used by pediatric eye doctors to slow myopia progression. While effective, such doses cause light sensitivity and blurry near vision while on the nightly eyedrops. Thus, there is interest in clinical studies assessing lower concentrations that have been shown to have fewer side effects.

“The absence of a treatment benefit in our US-based study, compared with East Asian studies, may reflect 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 with other races,” noted the study’s lead co-author, Michael X. Repka, M.D., professor of ophthalmology, Johns Hopkins University.

For the study, 187 children ages 5 to 12 years with low-to-moderate bilateral myopia were randomly assigned to use nightly atropine (0.01%) (125 children) or placebo (62 children) eyedrops for two years. Study participants, their parents, and the eye care providers were masked to the group assignments.

After the treatment period, and 6 months after treatment stopped, there were no significant differences between the groups in terms of changes in degree of myopia compared with baseline. Nor were there significant differences in axial length within the two groups when compared with baseline measurements.

“It’s possible that a different concentration of atropine is needed for US children to experience a benefit,” noted the study’s other lead co-author, Katherine K. Weise, OD, professor, University of Alabama at Birmingham. “Clinical researchers could evaluate new pharmaceuticals and special wavelengths of light in combination with optical strategies, like special glasses or contact lenses, to see what works in reducing the progression of myopia.”

Among children, myopia will stabilise in about half of children around age 16 years, and among an increasingly larger percentage as they get older. By their early twenties, about 10% of individuals with myopia will continue to grow more nearsighted, and by age 24 years that percentage is 4%.

“Vision scientists may help us figure out what’s different about the myopic eye, even among different races and ethnicities, to help create new treatment strategies,” she said. It will take a real convergence of eye research to solve the environmental, genetic, and structural mystery of myopia.”

Source: NIH/National Eye Institute