The global obesity crisis is regularly in the headlines, but there is little awareness of another global health epidemic that is twice as prevalent as obesity and growing at a much faster rate.
There are now up to two and a half billion people worldwide diagnosed with myopia, more commonly known as short-sightedness, with more than one million new cases every week – and this is estimated to rise to five billion by 2050.
The condition now affects around half of young adults in the US and Europe, double the prevalence of half a century ago, and up to 90 per cent of teenagers and young adults in Asia. In Seoul, the capital of South Korea, an alarming 96.5 per cent of 19-year-old men are short-sighted.
What’s particularly worrying is that myopia is being diagnosed earlier in school-going children and rising in severity.
A child with one short-sighted parent has three times the risk of developing myopia, or six times the risk if both parents are myopic. More and more children and teens with no family history of myopia are now being diagnosed with the condition.
Prof James Loughman, director of the Centre for Eye Research Ireland (CERI), Dublin Institute of Technology, warns that if measures are not taken to address the myopia epidemic, all children will be wearing glasses to school in the not-so-distant future.
Smartphones and mobiles
It is inevitable that fingers will be pointed at the use of smartphones and mobile devices in young children, but Prof Loughman points out that there is not enough evidence to suggest that this alone is to blame for the increase in myopia which started before the advent of technology.
“The fact that myopia has spread so quickly over the last 50 or 60 years suggests that this is not genetic, but an environment-driven phenomenon and strongly linked to our changing pattern of lifestyle. Kids start school at an earlier age and are spending more years in the educational system. They are spending a lot more time indoors – whether in school, doing homework or on a smartphone, device or computer – and less time outdoors. Being outdoors seems to be protective against myopia and the lack of time children spend outdoors is one of the strongest factors that seems to be driving this increase.”
Research carried out at DIT found that the vast majority of parents (85 per cent) regarded myopia as a lifestyle inconvenience rather than a health risk. However, Prof Loughman warns that being short-sighted is the third leading cause of blindness in Ireland as it is a risk factor for developing sight-threatening complications such as cataracts, glaucoma, retinal detachment and the untreatable condition, myopic maculopathy.
“You see very young kids in restaurants and cars holding phones and tablets close to their eyes and this definitely has to be a factor in children becoming short-sighted younger and getting worse faster. The younger myopia starts, the faster it progresses and the higher the risk of developing a complication later in life,” he explains.
In Prof Loughman’s view, just giving a child with myopia a pair of glasses and seeing them a year later for a checkup and increased prescription if needed is “bordering on negligence”. Parents should be advised of the risk factors for blinding complications and given education on how to slow down the progression of the condition, he says.
On a positive note, Prof Loughman points out that while no intervention has been found to stop the rise of obesity at a population level, there are successful treatments available to slow the progression of myopia in children. CERI has started a study into the use of low dose atropine eye drops in Caucasian children to treat myopia. The drops have been shown to reduce the risk of blindness by up to 80 per cent in children with myopia in Asia and in some cases, to stop progression. CERI is inviting parents who are interested in enrolling children aged 6 to 16 years onto the Myopia Outcomes Study of Atropine in Children (Mosaic) trial to contact it at firstname.lastname@example.org to discuss eligibility.
There are also special contact lenses available which slow the progression of myopia and can be worn daily or overnight.
“Kids who have myopia should be treated. It may never cause them any difficulty other than wearing glasses, but they are at an increased risk of developing blinding conditions and there is something we can do to prevent this if we intervene early enough. We need to figure out the kids who are at risk and this can easily be done by measuring the size of the eye using an instrument which is shone into the eye. If there is any sign that the eye is growing faster than it should, then we know they will become short-sighted and it’s time to intervene. This would require changes to the public health policy for child development,” says Prof Loughman.
He points out that people who have had laser surgery still have the same risk factors for complications that could lead to vision loss as they had before the treatment.
Galway optometrist Andrea Concannon believes it is the duty of eyecare practitioners to educate their short-sighted patients (and their parents) about the high risk of vision loss and what they can do to prevent this from happening.
As well as seeing short-sightedness in much younger children and far more often, Concannon, who specialises in paediatrics, is now seeing the children of parents who were never shortsighted themselves.
“The earlier you become short-sighted, the more likely you are to have problems in adulthood like glaucoma, cataracts and retinal detachments. I saw a child recently who had a 25 per cent deterioration in her sight in the space of only six months. I had another child under 10 in here last month with double vision in the distance after overdoing it on the iPad for the weekend. When you look at things up close for a long period of time, your eyes get used to that focus and the muscle goes into spasm.”
As a mother of four children aged 6 to 14, Concannon has first-hand experience with the battle that goes on in many homes when trying to get children off mobile devices. She bought a timer for each of her children and insists they take a screen break every 20 minutes as recommended by research.
“Twenty years ago, we were telling the kids to get outside away from the TV. Now I’m delighted if they’re watching TV because it means they are not on devices using their near vision. When I qualified, kids were using 70 per cent distance vision and 30 per cent near vision but that has totally flipped on its head,” she says.
What is it?
Myopia, also called near-sightedness or short-sightedness, is an eye condition where objects nearby or a short distance away like book or phones are clear, but objects that are far away like blackboards or TVs are blurred. It is caused by the eyeball being slightly too long. This physical change cannot be reversed.
Why are children more at risk?
In younger children, myopia progresses more quickly because their eyes are growing at a faster rate, leading to higher levels of myopia, stronger glasses and more eye health risks. A child with low myopia in second class most likely won't be able to read the biggest letter on the eye chart by the time they reach sixth class. It is recommended that children spend no more than two hours a day – outside school time – on near tasks including homework, hand-held devices, reading and Lego. Children under the age of two years should have no exposure to screens and two to five year olds no more than one hour per day.
How can you prevent or slow myopia in your child?
– Regular breaks of a few minutes every 20 minutes are recommended.
– Recommend the child looks away or changes their focus into the distance, eg TV, looking out the window, going for a walk.
– On weekends, ensure a balance between inside and outside time. Less screen time, more green time.
– If your child is diagnosed with myopia, ask your opthalmologist or optometrist for advice on interventions to slow the progression of the condition.