Diabetes and the eyes are closely related. Those who have diabetes have to regularly screen their eyes in order to make sure they don’t start to suffer from a range of diabetes-related conditions. One of these conditions is macular degeneration.
About Diabetes
When your body is not able to create sufficient insulin, an important hormone, or when insulin no longer has the desired effect, diabetes occurs. Insulin is vital to ensure our body can properly handle carbohydrates and sugars. Sometimes, children are born with diabetes, but it is much more common for it to develop later in life, particularly as a result of obesity. There are four main types of diabetes, as explained in the table below.
| Type of Diabetes | Characteristics |
| Type 1 | This usually happens before people turn 30 and happens when your body no longer produces any (or not much) insulin. Usually, people with type 1 diabetes have to take insulin injections, which is why type 1 is also known as ‘insulin dependent diabetes’. |
| Type 2 | This usually happens after people turn 40. The body still produces insulin, but it either doesn’t produce enough or it simply doesn’t work as it should. Usually, tablets, exercise and diet are used to control this. |
| South Asian Communities | Interestingly, people from South Asian communities, and particularly Sri Lanka, Bangladesh, Pakistan and India, are 25% more likely to develop type 2 diabetes after they turn 50. It is not known why, but although this is technically classified as type 2 diabetes, it is now almost recognized as a type in its own right. |
| Gestational diabetes | This is a type of diabetes that some women get when they become pregnant. It usually goes away after they have given birth, although the chance of developing type 1 or type 2 later in life is increased. |
How the Eye Works
The eye works by filtering light that hits the eye. The retina is responsible for most of this, converting light into signals that the brain interprets as pictures. The retina requires a blood supply and diabetes sometimes damages these vessels.
When light enters your eye, it does so through the macula, which is the central part of the retina. It is tiny, about the size of a pinhead, but incredibly important. Thanks to the macula, you can read and write, recognize colors and more. The larger part of the retina is only responsible for peripheral vision.
Diabetes and Your Eye
There are a few ways in which diabetes can affect the eye:
• Diabetic retinopathy, which is the most serious one of all
• Blurring of vision, caused by the lens being affected by the fluctuating levels of sugar in your blood
• Cataracts, whereby the eye goes cloudy
Many people with diabetes never develop eye problems. Those that do develop them often only have mild forms. However, the risk of developing these types of problems is much higher than what it is with people without diabetes, so it is important to be aware of it.
Macular Degeneration
Macular degeneration, or AMD (Age-Related Macular Degeneration), is one of the main causes of blindness in those over 65. With AMD, the macula is affected, meaning those affected struggle to see clearly.
There are two types of AMD:
1. Neovascular AMD – wet
2. Non-neovascular AMD – dry
Dry AMD is most common and is usually what happens in the early stages. Wet AMD means abnormal blood vessels start to form under the macula, leaking blood and fluid as they are very weak. As a result, sufferers often have blind spots or see distorted, gray, blurry areas.
AMD does not affect the peripheral vision, nor does it cause complete blindness. There are a number of risk factors associated with it, including sun exposure, sunlight, diet, age, genetics, and diabetes. AMD cannot be cured, but there are things that people can do in order to slow it down and even push it into some form of remission.
Lifestyle changes are the most important thing when it comes to managing AMD. As such:
• You must stop smoking.
• You must eat plenty of colorful vegetables and fruits full of antioxidants.
• You must eat omega 3 nuts and fish.
• You must manage any other health conditions you have.
• You must have a healthy BMI.
• You must take antioxidant vitamins as a supplementation, but only if medically recommended.
• You must protect your eyes from the sun.
Symptoms to look out for include:
• Slowly being unable to see clear details
• Slowly losing the ability to see color
• Blurry, distorted vision
• Empty or dark areas in the center of your vision
Some Important Pointers
If you are diabetic:
• Early detection is the most important thing.
• You must attend all you eye screening appointments.
• You should immediately have your eyes checked if you notice any change.
• You should communicate clearly with your eye clinic.
• You could be helped with laser treatment.
• You must always control your diabetes as recommended by your medical professional, which means attending clinics as well.
• You should stop smoking.
Risk Factors
With macular degeneration, there are risk factors that you can and cannot control. We have already discussed the things that you can do to reduce your risk, including changing your lifestyle and keeping to your medical appointments. Unfortunately, there are a few things that you cannot control. These include:
• How long you have had diabetes (this is not the same as how long you have been diagnosed). The longer you have had it, the more likely it is that you will develop AMD.
• Your age
• Your ethnicity. Those with South Asian diabetes are also more likely to develop AMD.
Treatment Options
With dry AMD, there is unfortunately no cure. You will receive care from an ophthalmologist to monitor further regeneration. Screening must also continue if you still have one healthy eye.
With wet AMD, a number of treatment options exist. A few of these fully restore vision. However, they will help vision improve and, most importantly, prevent complete loss of vision. Some of the most popular treatment options include:
• Medication, particularly Macugen, Lucentis and Eylea. These are not daily medications and are given under supervision of a medical professional.
• Laser photocoagulation, which destroys the abnormal blood vessels. This is effective in between 10% and 20% of people and some vision loss may also occur. Without it, however, there could be more vision loss.
• Photodynamic therapy, which is also a type of laser treatment. Instead of going through the eye, however, it gets to work inside the abnormal blood vessels, sealing off the ones that leak. Unfortunately, this is not a permanent solution as new blood vessels will start to form and break.
• Vitamins, which have been shown to be effective in the AREDS (age-related eye disease study). In particular, vitamin C and E, zinc, beta-carotene and copper can help lower the risk of AMD. Additionally, DHAE was found to be beneficial, with higher levels of DHAE often leading to lower levels of ADM. DHAE is available as an over the counter supplement in most stores.
Resources and References:
Macular Degeneration – Information on macular degeneration and diabetes. (Diabetes Self-Management)
Macular Degeneration – Information on the link between diabetes and macular degeneration. (I-Care.net)
Treatment of Neovascular Age-Related Macular Degeneration in Patients with Diabetes – Treatment of macular degeneration in diabetes patients. (NIH.gov)
Diabetes Mellitus and Early Age-Related Macular Degeneration – Connection between diabetes and macular degeneration. (NIH.gov)
Age Related Eye Disease Study – Research on age-related eye disease. (NIH.gov)
