How can we set myopia control expectations?

There is a clinical imperative now to both correct and control childhood myopia - the recent World Council of Optometry (WCO) Resolution has stated that optometrists should incorporate a standard of care for myopia management into their practices. This starts with a conversation on myopia risks, and continues into enacting myopia management strategies.

As you get started with a myopia management strategy for a particular child, though, how can you select the best treatment for them? How can you determine the success of the treatment? Here we utilize the Johnson & Johnson Vision Managing Myopia Guide, free to download, as a reference to support your clinical thought processes and communication.

With numerous spectacle, contact lens and pharmacological interventions for myopia control, how do you select which is best? A recent analysis entitled Efficacy in Myopia Control makes this simple. Through a detailed, comparative analysis of the absolute effects of myopia control treatments, it appears that the best of each of the treatment categories offer similar efficacy, with most of the effect being observed in the first year of treatment and similar results thereafter.¹

The exceptions to this rule? Progressive addition spectacle lenses, 0.01% atropine and "soft multifocal contact lenses that prioritize clear vision" appear to have lower efficacy than the rest.¹ The Johnson & Johnson Vision Managing Myopia Guide notes that "knowing efficacy is similar across treatments, it is most critical that the treatment regime fits the patient's lifestyle, expectations, motivation and their abilities."

You can personalize myopia control therapy by selecting treatments based on the clinical and lifestyle considerations of the individual patient. This diagram, from the Johnson & Johnson Vision Managing Myopia Guide, is designed to help guide collaborative decision making between the practitioner, parent and patient.

There are some key messages on this from the literature.

Firstly, some myopia progression is to be expected. Eye growth occurs in all young patients, even with stable emmetropic eyes which grow by around 0.1mm per year between ages 6 and 14. That doesn't mean that myopia progression is normal, or healthy though, as every additional dioptre of myopia increases lifelong risk of eye diseases.²

Secondly, myopia control treatment should start early and continue beyond the teenage years. Ensure parents understand that starting early, when myopia progression is fastest, can mean the treatment is more effective in absolute terms. When it comes to stopping treatment, since half of young myopes are still progressing at age 16,³ and around one-fifth of young adults appear to progress by 1D or more in their 20s,^4,5 if treatment is well tolerated it is ideal to continue throughout childhood and into early adulthood.

Utilizing the latest knowledge on efficacy, we can judge the success of a treatment against the efficacy in randomized controlled trials, and when referenced to the average progression observed in age-matched children wearing single vision correction - representing an 'untreated' condition. There are two key points here.

Firstly, myopia control efficacy is absolute, not relative. Be cautious when using percentages to explain efficacy - these are only valid over the duration of the particular study, and many factors can influence the percentage reported in a scientific study.

The average myopia control treatment effect found in numerous clinical studies points to a cumulative (total) effect over a two to three-year period of 0.30 to 0.40mm less axial length, or 0.75 to 1.00D less final myopia.

Secondly, evaluate progression using at least one (1) year of data to avoid seasonal changes in progression and reduce measurement noise - more data provides a better idea of trends. While it's not possible to determine treatment efficacy for an individual patient - because their untreated progression isn't known and past progression isn't a reliable future predictor - you can compare annual progression to see if it's slower than 'average'.

What is 'average' myopia progression? This table below, from the Johnson & Johnson Vision Managing Myopia Guide, provides the average axial and refractive progression by age for children of Asian and non-Asian ethnicity, based on meta-analysis data.

By virtue of providing averages, some children will progress faster or slower than the average, even when a myopia control strategy has been implemented. If a treatment doesn't appear to be slowing myopia as much as expected, consider factors such as the frequency and usage of the treatment. Is the patient compliant, and are they comfortable and satisifed with the treatment? Ensure that their goals for their vision correction are achieved as well as providing suitable myopia control intervention.

If a child is progressing faster than 'average', this could be due to a variety of factors, including younger age, a family history of myopia and visual environment experience such as increased near work at a shorter distance and less time spent outdoors. Read more about gauging and managing myopia outcomes in Why isn’t the myopia control strategy working?

Referring back to the table above can provide a gauge for a child who may be progressing faster than average and hence may require re-evaluation of expectations, revisiting the best treatment, more frequent review or starting a combination treatment with atropine.⁶

Download the Johnson & Johnson Vision Managing Myopia Guide here

• Case study: Is Switching The Myopia Control Strategy Necessary If There Is Myopia Progression?

• Case study: Can We Reconsider Contact Lenses?