Child myopia – an emerging health issue

Myopia (also called short-sightedness) is set to become the leading cause of permanent blindness worldwide.¹ By 2050, it is expected that 50% of the world’s population will be affected – this includes approximately 10% of people having the severe form.¹ This trend is a critical issue because the earlier a child gets myopia, the more severe it can become.²

Severe forms of myopia (called high myopia) are associated with many potentially sight-threatening eye conditions.

Australia will fare no different – it has been estimated that more than 50% of Australians will also be short-sighted by 2050.³ Parents are encouraged to educate themselves about myopia and the steps they can take to reduce the risk of their child developing the condition.

What is child myopia?

Myopia is a type of refractive error and occurs because the shape of the eyeball causes light rays to focus in front of the retina, rather than on it.

The result is blurry, out-of-focus distance vision. On average, eyes that have myopia are larger and longer than those without it. Child myopia specifically refers to myopia in someone under the age of 18, i.e. during school-age – this is why it’s sometimes also called ‘school myopia’. Child myopia is most commonly diagnosed in childhood.

What causes child myopia?

Every child is potentially at risk of developing myopia.

The likelihood of developing myopia is much higher in children with affected relatives and children living in urbanised environments.⁴

It’s also higher in some ethnicities, especially East-Asian populations. Children who have short-sighted parents have a several-fold higher risk of being affected themselves.⁵ There are also lifestyle factors that can increase your child’s risk of developing myopia, including:

• inadequate time spent outdoors⁶
• lack of exposure to natural sunlight⁷
• long periods focusing on near-vision tasks, such as reading or using electronic devices.⁸

What are the long-term risks?

The milder forms of myopia do not typically pose a significant risk to your child long-term. However, the condition is often progressive, meaning that it becomes worse over time as the eye grows and changes. This includes during puberty when rapid bodily development occurs.⁹ The most severe form is known as high myopia. High myopia is associated with a higher risk of developing serious eye conditions later in life, including retinal detachment, glaucoma, cataracts and myopic macular degeneration.¹

Can child myopia be reversed?

Child myopia is irreversible, but treatments are available that can restore distance vision, such as glasses or contact lenses. However, these do not stop myopia from becoming worse.³ Vision correction surgery (e.g. laser eye surgery) is generally not recommended in children, because their eyes continue to develop into early adulthood. Alternatively, special multifocal lenses (glasses or contact lenses) have been found to slow the progression of the condition, as have corneal-reshaping contact lenses (orthokeratology or Ortho-K). Ortho-K lenses are worn at night to temporarily reshape the corneal surface so that glasses aren’t required during the day. One drop per day of low-dose atropine (0.01%) has been shown to be effective in limiting the progression of myopia in several large clinical trials. Your child’s eyes will generally stabilise after the age of 18, at which time laser eye surgery may be considered for vision correction.

Although vision correction surgery may remove the need for corrective glasses or contact lenses, the risk of developing sight-threatening complications remains lifelong.

Can child myopia be prevented?

You can reduce the risk of your child developing myopia by limiting their time on near-vision tasks such as reading or using electronic devices.

Children should also have plenty of time outside – ideally two hours every day.

This also has other added health benefits such as increased blood levels of vitamin D, which is responsible for maintaining good bone and muscle health.¹⁰ For children who have already developed myopia, early detection provides the best chance of slowing down its progression and reducing the risk of serious complications later in life. Children should have their vision tested by an optometrist before starting school, and then regularly every two years afterwards. If the myopia is shown to be progressing, it is important to discuss possible ways in which to prevent further deterioration.

What about a child with myopia and astigmatism?

Astigmatism is where the cornea of the eye is irregularly curved and results in blurry vision. It is another common refractive error and children with myopia are also likely to have astigmatism. Glasses and contact lenses can be used to correct both conditions at the same time.