I’m short-sighted: am I at risk of developing cataracts?
I’m short-sighted: am I at risk of developing cataracts?
Short-sightedness, or myopia, is a very common eye condition that affects an estimated 1.4 billion people worldwide. In people who are myopic, light entering the eye does not focus onto the retina, making it difficult to see objects that are far away.
For most people, treating myopia is as simple as wearing prescription glasses or contact lenses to correct their vision. But for people with high myopia there is sometimes a greater risk of developing other eye conditions, including cataracts. To help you understand whether you may be at risk of developing cataracts, we’ll take a closer look at the link between the two conditions, and what you can do to prevent them.
What is short-sightedness and how does it affect vision?
If someone is myopic or nearsighted, close objects appear sharp and well-defined, but objects at a distance appear blurred. As such, nearsightedness may not affect someone’s ability to read a book or look at a computer screen, but it makes it difficult to watch a film, read a whiteboard in a classroom, or to see clearly when driving.3, 4 While these symptoms can be easily managed with prescription glasses or contact lenses, undiagnosed nearsightedness can sometimes cause eye strain and headaches, or squints in children.
What are the treatment options for cataracts?
More severe cases of short-sightedness are categorised as high myopia. Conventionally, an eye is considered to have high myopia if it requires -6.0 dioptres (lens strength) or more to correct vision. About 10% of people with nearsightedness will have high myopia, which places them at an increased risk of developing eye conditions such as glaucoma and cataracts.1, 2
What causes short-sightedness?
Nearsightedness occurs because the cornea (the clear part at the front of the eye) is too curved or the eyeball itself is too long. Both of these scenarios mean that instead of focusing the image on the retina (the light-sensitive layer in the eye), the lens forms the image in front of the retina. This is what makes distant objects appear distorted and blurred.3,4
Although the exact cause of nearsightedness is still unclear, researchers have identified some key risk factors. One of these factors is genetics, as myopia tends to run in families, with children being three times more likely to develop myopia if one parent is short-sighted, and seven times more likely to be myopic if both parents have the condition.
However, myopia can also occur in adults due to visual stress or medical conditions such as diabetes. Alongside this, environmental factors also play a role in myopia development. If you spend considerable time indoors staring at screens, reading, or doing other work that requires intense close vision, your risk of myopia may be higher.4
What are cataracts and how do they impact vision?
A cataract is a clouding of the lens in the eye. The lens is the structure that focuses light onto the retina to form images. In healthy eyes, the lens is transparent, however, people with cataracts will see cloudy or blurry patches in their vision (like looking at objects through a dirty or fogged-up windshield).5
The most common cause of cataracts is ageing. By the age of 60 to 65, most people have at least some degree of lens opacity. However, other eye conditions such as myopia and medical conditions like diabetes can also cause cataracts to develop. Some inherited genetic disorders have also been found to increase your risk of cataracts.
Although bothersome, cataracts can be easily treated. Cataract surgery is the only effective treatment to remove cataracts, with the majority of people who undergo it reporting improved vision afterwards.6 It involves removing the clouded lens and replacing it with an artificial one. You can learn more about cataract surgery here.
What is the link between nearsightedness and cataracts?
While treating myopia is usually as simple as wearing prescription glasses or lenses for most people, research has found a link between high myopia and the development of cataracts.7 In particular, one study found that cataracts are more likely in people who began using distance glasses before the age of 20, as well as in people above the age of 55 who develop nearsightedness.7, 8
While the precise link between high myopia and cataracts is not completely clear, it is believed that severely myopic eyes have reduced levels of protective antioxidants, which could make them more prone to developing cataracts.7
What are the first signs of cataracts?
Most cataracts develop slowly and don't disturb your eyesight early on, but there are a few symptoms you can look out for. Before cloudy vision develops, cataracts patients can experience difficulty with night vision, colours appearing faded, and seeing haloes around lights. As the cataract grows in size, it can impact vision on a day-to-day basis, making it difficult to read, watch TV, drive, or perform other activities of daily living.5
I’m nearsighted — how can I reduce my risk of cataracts?
Most cases of cataracts can be easily treated with surgery. However, it’s still understandable to be worried about your vision — especially if you are nearsighted. Below we’ve outlined a number of steps that can help to minimise the risk of developing cataracts:9
- Quit smoking
- Drink alcohol in moderation
- Eat foods rich in antioxidants and vitamins, such as fruit and green leafy vegetables
- Protect your eyes from UV damage by wearing high-quality sunglasses
- If you are diabetic, keep your blood sugar under control
If you suspect that you may have cataracts, it’s best to make an appointment with an optician. Regular eye exams make it possible to spot problems such as cataracts early on. For more information on cataracts, please visit our dedicated resource. Alternatively, you can book an appointment with a Specsavers optometrist.
References
1. The Independent. (June 6, 2018). Short-sightedness increases with every year in education.
[Online]. Available at:
https://www.independent.co.uk/news/health/short-sighted-glasses-eyes-education-myopia-children-singapore-korea-blindness-a8386071.html
[Accessed 31 August 2019].
2. National Eye Institute. (no date). Facts About Myopia. [Online]. Available at: https://nei.nih.gov/health/errors/myopia
[Accessed 31 August 2019].
3. American Optometric Association. (no date). Myopia (nearsightedness). [Online]. Available at:
https://www.aoa.org/patients-and-public/eye-and-vision-problems/glossary-of-eye-and-vision-conditions/myopia
[Accessed
31 August 2019].
4. National Eye Institute. (no date). Facts About Myopia. [Online]. Available at: https://nei.nih.gov/health/errors/myopia
[Accessed 31 August 2019].
5. Mayo Clinic. (no date). Cataracts. [Online]. Available at:
https://www.mayoclinic.org/diseases-conditions/cataracts/symptoms-causes/syc-20353790
[Accessed 31 August 2019].
6. National Eye Institute. (no date). Facts About Cataract. [Online]. Available at:
https://nei.nih.gov/health/cataract/cataract_facts
[Accessed 31 August 2019].
7. Younan C, Mitchell P, Cumming RG, Rochtchina E, Wang JJ. Myopia and Incident Cataract and Cataract
Surgery: The Blue
Mountains Eye Study. Investigative Ophthalmology & Visual Science. December 2002, Vol.43, 3625-3632.
[Online]. Available
at: https://iovs.arvojournals.org/article.aspx?articleid=2162247
[Accessed 31 August 2019].
8. Brown NA, Hill AR. Cataract: the relation between myopia and cataract morphology. Br J Ophthalmol.
1987;71(6):405–414.
[Online]. Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1041188/
[Accessed 29 August 2019].
9. WebMD. (no date). How can I prevent cataracts? [Online]. Available at:
https://www.webmd.com/eye-health/cataracts/how-can-i-prevent-cataracts#1
[Accessed 31 August 2019].

Hayley Moore
MOptom (Hons) MCOptom Dip Tp(IP) Prof Cert Glau Prof Cert Med Ret
Hayley is an optometrist and prior to joining Specsavers in 2016 has worked in a variety of settings, including hospital and independent practice. Most notably, Hayley was National Optometry Development Manager for Ultralase, and is a refractive surgery and intra-ocular lens specialist… Read more