In 2004 a study of myopia in Taiwanese schoolchildren, using data gathered between 1983 and 2000, concluded that myopia was starting to develop at a "very young and progressively decreasing age." [1] As a result, the study recommended that more attention should be paid to the eye care of preschool children.
A UK Biobank study published in 2022 echoed the findings of the Taiwanese report. [2] The records of more than 100,000 individuals born between 1939 and 1970 revealed a rise in myopic frequency from 20% in older participants to nearly 30% in the youngest cohort.
Was that rise in myopia a product of its time, or is that trend continuing? Are we still seeing myopia developing at an earlier age, and if so, what interventions are needed to try and address the problem?
Well, sadly, it seems as though childhood myopia is still on the rise. A Chinese study which looked at whether lockdown had affected myopia in children concluded that
“Following lockdown and home-schooling, children showed both greater amounts of myopia and a higher prevalence of myopia than in the preceding five years.” [3]
More importantly, the most significant increase in myopia was seen in younger children.
Admittedly, that study focused on the lockdown period in which children were expected to stay home for long periods, particularly in China. So are the findings particular to the pandemic, and will we, therefore, see a gradual reduction in the number of individuals developing myopia as life returns to normal?
Whether we may see a slight correction in the numbers of children developing myopia remains to be seen. However, a Northern Ireland study (NICER) which began in 2006, suggests that rising numbers of children with myopia is likely to remain a cause for concern.[4] Key findings from the NICER study reveal that not only has the number of UK children with short sight doubled over the last fifty years, but children are also becoming short-sighted at a younger age than previously thought.
Why does this rise in the early development of myopia matter? Once myopia starts to develop, it can go on developing throughout childhood and the teenage years. The earlier that myopia develops, the greater the chance that an individual may end up with a more severe form of myopia, potentially leading to several eye conditions, which may lead to sight impairment or blindness in later life. That conclusion was echoed by a study reported in 2021, which concluded that "the most important risk factor for myopia progression is younger age." It also found that "young age and higher myopia at baseline were strongly associated with the risk of developing high myopia." So much so that the five-year cumulative risk for the youngest teenagers studied with higher myopia was 76%. [5] In other words, the earlier an individual develops myopia and the more that myopia develops, the greater the chance of further problems in later life.
With that in mind, what are the options for parents who want to reduce the chances of their children developing myopia at an early age or developing the more severe form of the condition?
First and foremost, the importance of early and regular eye checks cannot be emphasised enough. The earlier that myopia is identified, the sooner a myopia management plan can be put in place. Whilst it is generally not possible to reverse myopic development, appropriate interventions can help slow down myopia's development, reducing the chance of severe myopia and visual complications developing in later life. These interventions include wearing special lenses, which not only correct vision changes but also manage how the light enters the eye. This, in turn, helps to reduce the conditions inside the eye, which can cause the eyeball to grow abnormally, potentially leading to myopia.
Myopia development can be subject to both genetic and environmental factors. Whilst parents can do little about the genetic factors, by paying attention to environmental factors, it might be possible to reduce the chance of myopic development.
One lesson might be to monitor and manage children's time indoors on computers and other devices. As one study into myopia in lockdown showed, restrictions on outdoor time led to an increase in children developing myopia. Conversely, other studies have demonstrated how increased outdoor time helps to reduce the incidence of myopia. One Indian study published in 2021 concluded that:
“Each hour increase in outdoor activity per day had a protective effect on the progression of myopia.”[6]
As well as spending more time outdoors, children may benefit from being encouraged to take time away from computers when indoors. In a 2021 blog, Annegret Dahlmann-Noor, Consultant and Director of the Children's Eye Service at Moorfields Eye Hospital in London, advocated the '20-20-2' rule, which recommends that after twenty minutes of near work, individuals should gaze into the distance for at least twenty seconds, and spend at least two hours outside per day. [7] There was also a recommendation that close work is carried out at a distance of at least 30 cm.
That myopia is developing earlier than before is inescapable. But through early identification and intervention allied to an awareness of potential environmental trigger points, parents can help to ensure that their child's myopia is less severe than it otherwise might be, thereby providing a lifelong benefit for their children's sight.
If you're a parent whose child has been diagnosed with myopia or if they are struggling with their distance vision, we hope you found MyopiaFocus helpful. Please join our community or sign our petition to get the government and NHS to recognise myopia as an ocular disease/severe ocular condition and fund myopia management for children.