IMI Report on Prevention of myopia and its progression

Published:

Research Abstract Summary

Authors: Jost B. Jonas, Marcus Ang, Pauline Cho, Jeremy A. Guggenheim, Ming Guang He, Monica Jong, Nicola S. Logan, Maria Liu, Ian Morgan, Kyoko Ohno-Matsui, Olavi Parssinen, Serge Resnikoff, Padmaja Sankaridurg, Seang-Mei Saw, Earl L. Smith III, Donald T.H. Tan, Jeffrey J. Walline, Christine F. Wildsoet, Pei-Chang Wu, Ziaoying Zhu, James S. Wolffsohn

Date: April 2021

Reference: Jonas JB, Ang M, Cho P, Guggenheim JA, He MG, Jong M, Logan NS, Liu M, Morgan I, Ohno-Matsui K, Pärssinen O, Resnikoff S, Sankaridurg P, Saw SM, Smith EL 3rd, Tan DTH, Walline JJ, Wildsoet CF, Wu PC, Zhu X, Wolffsohn JS. IMI Prevention of Myopia and Its Progression. Invest Ophthalmol Vis Sci. 2021 Apr 28;62(5):6. (Link to open access paper)

Summary

The prevalence of myopia is increasing worldwide, particularly in East and Southeast Asia where it reaches approximately 80-90% among senior high school students. The pathologic consequences of myopia, including myopic maculopathy and high myopia-associated optic neuropathy, are now some of the most common causes of irreversible blindness. As a result, we need strategies to reduce the prevalence of myopia and the progression to high myopia. This study summarises the evidence regarding various interventions and makes recommendations for clinical practice. 

1.Increased time spent outdoors

On the basis of published population-based and interventional studies, an important strategy to reduce the development of myopia is encouraging schoolchildren to spend more time outdoors. The Sydney Myopia Study showed that exposure to more than two hours of time spent outdoors daily was associated with a reduced odds of myopia, even in children who engaged in high levels of near work. Studies demonstrate that increasing the amount of time spent outdoors decreased the incidence of myopia in children. As compared with other measures, spending more time outdoors is the safest strategy and aligns with other existing health initiatives, such as obesity prevention, by promoting a healthier lifestyle for children and adolescents.

The underlying mechanism for the myopia controlling effect of outdoor time has not been fully elucidated. However, proposed reasons include factors such as higher light intensities, variations in the chromatic light composition, differences in dioptric topographies, less near work, and a decrease in the accommodative demand.

2. Clinical measures: including pharmacological and optical interventions

Clinical measures to reduce or slow the progression of myopia include the daily application of low-dose atropine eye drops (between 0.01% and 0.05%); multifocal spectacle design; contact lenses that have power profiles that produce peripheral myopic defocus; and orthokeratology. The authors summarise existing evidence regarding the use of various concentrations of atropine for myopia control, including ATOM-1, ATOM-2 and a Cochrane review performed by Walline and colleagues. The risk-to-benefit ratio needs to be weighed up for the individual on the basis of their age, health, and lifestyle. Importantly, the measures listed above are not mutually exclusive and are beginning to be examined in combination.

3. General considerations and limitations 

The various treatment modalities have not directly been compared with each other, and therefore one cannot state an order of treatment such as therapy of first choice or second choice. Before specific guidelines about the choice of new treatments for an individual can be given, results from independent well-designed controlled longer-term studies should be obtained. With respect to the long-term sequelae of a therapy potentially applied to millions of children and adolescents, potential side effects of a pharmaceutical therapy, such as atropine, may not become apparent until several decades after its adoption.

What does this mean for my clinical practice?

All parents and children should be advised of increasing time spent outdoors to combat myopia. This article provides a relevant summary of the pharmacological and optical interventions that can be implemented in clinical practice to slow myopic progression.

What do we still need to learn?

There is still a lot to learn in regards to myopia prevention and its progression. Regarding atropine, questions to be addressed in future studies include when to start the atropine therapy, the optimum dose, frequency and time of application, duration of treatment, the potential rebound phenomenon and long term effects including safety. We know soft multifocal contact lenses slow the progression of myopia, but questions remain about the optimum distribution of refractive power to maximise efficacy while not impacting functional vision.

Abstract

Title: IMI Prevention of Myopia and Its Progression

Authors: Jost B. Jonas, Marcus Ang, Pauline Cho, Jeremy A. Guggenheim, Ming Guang He, Monica Jong, Nicola S. Logan, Maria Liu, Ian Morgan, Kyoko Ohno-Matsui, Olavi Parssinen, Serge Resnikoff, Padmaja Sankaridurg, Seang-Mei Saw, Earl L. Smith III, Donald T.H. Tan, Jeffrey J. Walline, Christine F. Wildsoet, Pei-Chang Wu, Ziaoying Zhu, James S. Wolffsohn

The prevalence of myopia has markedly increased in East and Southeast Asia, and pathologic consequences of myopia, including myopic maculopathy and high myopia-associated optic neuropathy, are now some of the most common causes of irreversible blindness. Hence, strategies are warranted to reduce the prevalence of myopia and the progression to high myopia because this is the main modifiable risk factor for pathologic myopia. On the basis of published population-based and interventional studies, an important strategy to reduce the development of myopia is encouraging schoolchildren to spend more time outdoors. As compared with other measures, spending more time outdoors is the safest strategy and aligns with other existing health initiatives, such as obesity prevention, by promoting a healthier lifestyle for children and adolescents. Useful clinical measures to reduce or slow the progression of myopia include the daily application of low-dose atropine eye drops, in concentrations ranging between 0.01% and 0.05%, despite the side effects of a slightly reduced amplitude of accommodation, slight mydriasis, and risk of an allergic reaction; multifocal spectacle design; contact lenses that have power profiles that produce peripheral myopic defocus; and orthokeratology using corneal gas-permeable contact lenses that are designed to flatten the central cornea, leading to midperipheral steeping and peripheral myopic defocus, during overnight wear to eliminate daytime myopia. The risk-to-benefit ratio needs to be weighed up for the individual on the basis of their age, health, and lifestyle. The measures listed above are not mutually exclusive and are beginning to be examined in combination.