Myopia - a global health & economic issue hurtling towards disaster
Myopia, or short-sightedness, or near-sightedness. They’re all the same condition and it’s getting worse at a scary rate. On top of that, we don’t know how to fully tackle it, because we don’t fully understand it. And we don’t have the data to plan for it.
“Although it's not clear exactly why some people become short-sighted” - NHS website
The World Health Organisation has been banging this drum for a long time, stating that eye health does not get enough attention from a public health perspective. They’ve published that the estimated number of people with myopia will increase from 1.95 billion in 2010 to 3.36 billion in 2030. For high myopia (over -5 diopters), from 277.2 million in 2010 to 516.7 million in 2030 [1].
They also previously estimated that levels of high myopia would be 10% of the global population by 2050 [2]. Which is frightening, considering that later in life this group will be more at risk from serious retinal damage, cataracts, glaucoma, and myopic macular degeneration (MMD) which can cause blindness. A request for information to NHS Digital revealed that they do not have any data on the nation’s prescription strength i.e. the UK government are not measuring levels of high myopia and sight deterioration, and therefore how can we be planning for our future eye healthcare needs.
So what causes myopia and why is it increasing in prevalence? The answer seems to lie in a mix of genes and environment. But given the speed at which the condition is getting worse, to what extent can we really blame genetics?
Research seems to agree that 2 broad factors relate to the cause of myopia degeneration: near work (e.g. looking at screens) & lack of time spent outdoors in daylight. Some researchers are also looking into sleep and diet as factors.
Near work
Think reading, looking at screens, knitting etc. When we focus close up, we use less of our peripheral vision, and we’re using the same eye muscle groups for long periods of time i.e. all day on a computer.
“38% of UK respondents to a survey carried out by Fight for Sight, said their eyesight had worsened since the start of the pandemic” [3]
This supports why longer schooling, and more intense school systems such as in China, have higher rates and severity of Myopia [1]. More and more children around the world are also gaining the opportunity to be educated, in which case we would expect to see global rates increase over time. Myopia is more than twice as prevalent among UK children now than in the 1960’s (16.4% vs 7.2%) [5].
But what specifically about near work can make it worse? For example screen brightness on digital devices, font sizes, room lighting, task intensity, or the distance between your eyes and what you’re looking at.
Available research doesn’t conclusively have an answer as to exactly what contributes the most towards sight deterioration.
Time outdoors
There is uncertainty on the variables that relate to being outdoors, and progression of myopia. Which notably includes natural light exposure, vitamin D absorption & looking into the distance more. Sunlight exposure also affects dopamine release which is related to controlling pupil size and light entering the eyes. Eye growth causes Myopia, which dopamine slows down.
So again we have a list of variables we can’t confidently state to what extent they relate to cause and effect.
Putting a price on sight
Myopia has enormous associated costs related to care, treatment, loss of productivity and quality of life;
- Annual global costs of productivity losses associated with vision impairment from uncorrected myopia alone were estimated to be US$244 billion [1].
- The economic burden of uncorrected myopia in the regions of East Asia, South Asia and South-East Asia were reported to be more than twice that of other regions and equivalent to more than 1% of gross domestic product [1].
- Reducing the rate of myopia progression by 50% could reduce the prevalence of high myopia by up to 90% [2].
- A 2012 study published by The WHO estimated loss in global gross domestic product due to distance vision impairment caused by uncorrected refractive error was US $ 202 billion annually, whilst the cost for fixing this is US $28 billion over 5 years [4].
To sum up, it seems that there are huge return on investments to gain by investing in sight. Not to mention, less people will be blind and still have one of their most precious senses.
Given current projections of increased rates of myopia and high myopia, are health care systems ready for this huge challenge? Or are we going to start investing in better prevention & care. This is a difficult cause to advocate because a lot of the cost savings to health services are not immediate, given that serious eye complications associated with refractive error commonly manifest above the ages of 70. But surely we need to be playing the long game?
Technology and eye healthcare access
In August 2022, the FDA in America approved their first ever online visual acuity test, by Visibly [7]. In 2021, Visibly also teamed up with other organisations to offer 5,000 free eye tests in Nigeria where access to vision care is expensive.
Similar testing initiates and technology have been rolled out in the UK. DigiVis is a web app with CE status that is currently undergoing trials which could see the NHS use it for at home visual acuity screening purposes [8].
Although the value of a full, in person eye assessment is invaluable, there is so much more we can do to make visual acuity only tests much more accessible through technology and the internet, in a move to help solve the myopia problem. In addition to easing the strain on healthcare providers.
Treatment & taking action
There has been some progress in slowing down and treating myopia, like atropine eye drops and specialist contact lenses [9]. A company called SightGlass Vision is also making very promising progress in lens technology that slows down myopia [6]. As is Hoya with their Miyosmart product and EssilorLuxottica who in September 2022 released the results of their 3 year clinical trial of their Essilor Stellest lenses which saved more than one diopter of myopia on average over three years.
An additional treatment being researched is red light therapy (RLRL) which involves a child looking into a device for a few minutes twice a day at home, that emits low level red light. Some UK opticians are now trialling a device from Eyerising as part of a pilot scheme [10].
But we need to be tackling the problem from all sides and focusing more on prevention.
Further data and research is needed to identify the exact cause and effect of degeneration so we can innovate and design solutions to help stop it. Overall, a focus must be on children because that's where the biggest opportunity seems to exist. This could range from reviewing accessibility guidelines on online platforms or text books (e.g. bigger default fonts - hello Mr Zuckerberg) and policing this more rigorously, visual acuity tests and screenings in schools, to reviewing classroom design and teaching styles, to making sure everyone has access to outdoor space and parks.
We also need more awareness and education on things like the importance of taking breaks from near work, looking into the distance regularly, and limiting screen time.
And we need more prescription and eye health data to determine the true extent of the issues - without which we can’t measure if any efforts are making an impact.
It’s really clear that these issues need urgent attention as the current evidence shows that we are hurtling towards disaster.
Footnotes:
[1] 2019, The World Health Organisation, World report on vision (who.int)
[2] 2015, The World Health Organisation, The Impact of Myopia and High Myopia
[3] 2021, Fight for Sight, Time to focus report
[4] 2012, Fricke T, Holden B, Wilson D, Schlenther G, Naidoo KS, Resnikoff S et al. Global cost of correcting vision impairment from uncorrected refractive error
[5] 2016, The Northern Ireland Childhood Errors of Refraction (NICER) study
[6] SightGlass Vision: Diffusion Technology / Trial finds SightGlass slows myopia progression
[7] 2022, Visibly becomes first FDA cleared online vision test in the United States
[9] The College of Optometrists - Childhood onset myopia management evidence review https://www.college-optometrists.org/category-landing-pages/clinical-topics/myopia/childhood-onset-myopia-management-evidence-review
[10] 2023, Optometry Today - UK Pilot for Myopia Management to be rolled out
