Refractive
December 2021
by Liz Hillman
Editorial Co-Director
Myopia, a condition that for decades has been described in some regions as an epidemic, is well on its way to reaching pandemic proportions.
A systematic review and meta-analysis published by Holden et al. in 2016 estimated that in 2000, 22.9% of the world’s population would be myopic and 2.7% highly myopic.1 The authors predicted that by 2050, nearly 50% of the global population would be myopic and nearly 10% highly myopic. A more recent paper looking at myopia in school-age children noted “exceptionally high myopia prevalence rates in school children in East Asia (73%), and high rates in North America (42%).”2
Though considered easily correctable with glasses, myopia and high myopia are associated with a risk of developing cataracts sooner and a higher risk for glaucoma and retinal issues, said Erin Walsh, MD. It’s been documented that myopia rates and myopia progression increase with more near work being performed, such as reading, homework, and screen time, Dr. Walsh said. “I tell my patients that the more reading we do, the higher rates of myopia we’re going to see. Countries where children are spending considerable time doing near work are seeing higher rates of increasing progressive myopia.”
Myopia, its progression, and the long-term issues that can be associated with it have been a topic for a while, Dr. Walsh said, with the conversation shifting toward how to slow down progression in recent years as trends of high population rates of myopia emerged.
Options to stall progression
There are many options to treat the optical problem of myopia, but they do not necessarily address the complications associated with myopia, which could still occur. Progression of myopia can, however, be mitigated in some cases.
The most common and well-researched therapies to try to prevent progression of myopia are low-dose atropine and orthokeratology.
Donald Tan, MD, said there have been many studies on reducing myopia progression over the years that have begun to come to fruition. Low-dose atropine has the best evidence for stalling myopia progression, he said. Certain contact lenses, some spectacles, and orthokeratology also have produced evidence that they help reduce progression, but Dr. Tan said it’s not as robust as the evidence supporting low-dose atropine, and some of these options have potential risks.
Orthokeratology and contact lens use, Dr. Tan said, is associated with a risk for infection and corneal ulcers. These risks are higher in the pediatric population than adults, he thinks, due to less attention to hygiene.
A closer look at atropine
Dr. Tan called low-dose atropine a paradigm shift. When in training, he was taught awareness with regard to the potentially sight-threatening complications associated with high or pathological myopia. Now, “we’re at the prevention stage, since it is a reasonable assumption that if we can reduce myopia progression so that less children ultimately develop high or pathological myopia, the percentage of subsequent complications associated with high myopia should also be less,” he said.
The Atropine in the Treatment of Myopia (ATOM) studies first enrolled 400 children aged 6–12 who had –1 D to –6 D of myopia. The patients were randomized to receive either 1% atropine or placebo.3 The researchers found significantly less progression of myopia in the atropine group. At 1 year, patients in the atropine group saw a regression of myopia by +0.3 D±0.50 D; axial length was reduced by –0.14 mm±0.28 mm. Patients in the placebo group progressed –0.76 D±0.44 D, and axial length increased +0.20 mm±0.30 mm. At year 2, mean myopia progression in the atropine group was –0.25 D±0.92 D with axial length remaining similar to baseline. The placebo group at year 2 saw progression of –1.20 D±0.69 D with axial elongation of +0.38 mm±0.38 mm. Since this study, even lower doses of atropine have been researched. The Low-Concentration Atropine for Myopia Progression (LAMP) study evaluated 0.05%, 0.025%, and 0.01% atropine against placebo; all concentrations were well tolerated, but 0.05% was most effective in controlling progression and axial length elongation over a year.4 The dose of 0.01% has been found to be effective in reducing myopia progression.5
While atropine is approved by the FDA for cycloplegia, mydriasis, and amblyopia treatment, the lower doses that are now being used for pediatric patients for stemming myopia progression are considered off label. It is obtained via a compounding pharmacy.
Before starting atropine, Dr. Walsh said she begins screening for progression. During that time, she recommends environmental changes to parents. Several studies have associated indoor time and near work with increased risk of myopia development. However, the effect of outdoor time might only be helpful in preventing myopia development as research has shown it doesn’t slow the progression in established myopes.6 The Shanghai Time Outside to Reduce Myopia trial is currently taking place as a randomized controlled trial to investigate the protective effect of outdoor time of various lengths in the development of myopia.
Dr. Walsh said longitudinal studies are being conducted to determine the ideal age to start taking a patient off atropine. When patients reach their late teens, Dr. Walsh said she stops atropine for 3–6 months, following up with them in this timeframe, seeing if it needs to be restarted or if the patient remains stable.
Dr. Walsh said some physicians will treat for a couple of years and stop and monitor, while others will treat until they think it is a safe age (15–18) for myopia to slow down and taper.
Dr. Tan also emphasized the need to document myopia progression before beginning a low-dose atropine use. He said screenings should begin earlier because research has shown younger ages for myopia onset are associated with greater myopia progression, leading to higher degrees of myopia in adulthood.
Looking forward
A literature and data review looked at efficacy of myopia control methods and reached several conclusions, including: Axial length rather than refractive error is the preferred metric for tracking progression; there is a reduction in myopia treatment efficacy over time with a need for more information on why and whether there’s a benefit to pulsing or changing treatment; and different treatments have “similar effect with some caveats.”7
“The clinician should choose the treatment based on numerous considerations such as their own skill set, preferences of parents and children, ability of the child to adapt to the treatment, as well as availability of product and regulatory considerations,” Brennan et al. said.
Dr. Tan said he hopes atropine will eventually receive full regulatory approval as a form of myopia control for children.
While Dr. Walsh thinks atropine is a great step forward in helping stem myopia progression, there are still things she thinks could benefit patients. These include the ability to get atropine either over the counter or at a regular pharmacy (versus a compounding pharmacy). The cost, $40–45/month, can be significant to some families. On a grander scale, she said having some method for identifying patients who are likely to develop myopia before it even starts would be the “silver bullet” to helping stop it before it starts. She noted that there are some syndromes, systemic disorders, and genetic conditions where even atropine won’t help the patient. Having treatments for those would be on her wish list as well.
Dr. Walsh said physicians should counsel the patients they see on the importance of getting their children screened if there is a history of myopia in the family. “Edify your patients to come and see [pediatric specialists] sooner and start screening children early,” she said.
Dr. Tan said that studies using low-dose atropine are beginning to look at preventing myopia before it even starts, evaluating whether it can be prevented altogether or onset delayed. Until that time, he said his message to the ophthalmic community is that there is finally an approach to reducing progression that appears to be both safe and effective. Beyond medical therapy, he said myopia is a problem that needs to be solved at different levels.
“It’s not only going to be solved by a pediatric ophthalmologist. … It’s going to be general ophthalmologists and other eyecare professionals as well. We know that schools have a role to play in myopia,” he said, noting that lifestyle changes across the board can help with this issue.
About the physicians
Donald Tan, MD
Clinical Professor
Eye & Cornea Surgeons
Eye & Retina Surgeons
Singapore
Erin Walsh, MD
Assistant Professor of Ophthalmology
New York Eye and Ear Infirmary of Mount Sinai
New York, New York
References
- Holden BA, et al. Global prevalence of myopia and high myopia and temporal trends from 2000 through 2050. Ophthalmology. 2016;123:1036–1042.
- Grzybowski A, et al. A review on the epidemiology of myopia in school children worldwide. BMC Ophthalmol. 2020;20:27.
- Chua W, et al. Efficacy results from the Atropine in the Treatment of Myopia (ATOM) study. Invest Ophthalmol Vis Sci. 2003;44:3119.
- Yam JC, et al. Low-Concentration Atropine for Myopia Progression (LAMP) study: A randomized, double-blinded, placebo-controlled trial of 0.05%, 0.025%, and 0.01% atropine eye drops in myopia control. Ophthalmology. 2019;126:113–124.
- Larkin GL, et al. Atropine 0.01% eye drops for myopia control in American children: A multiethnic sample across three US sites. Ophthalmol Ther. 2019;8:589–598.
- Li SM, et al. Time outdoors and myopia progression over 2 years in Chinese children: The Anyang Childhood Eye Study. Invest Ophthalmol Vis Sci. 2015;56:4734–4740.
- Brennan NA, et al. Efficacy in myopia control. Prog Retin Eye Res. 2021;83:100923
Relevant disclosures
Tan: Eye-Lens, Santen
Walsh: None
Contact
Tan: dt@ers.clinic
Walsh: ewalsh@nyee.edu
