Diabetic Eye Disease
What is diabetic eye disease?
Diabetic eye disease is a group of eye problems that can affect people with diabetes. These conditions include diabetic retinopathy, diabetic macular edema, cataracts, and glaucoma.
Over time, diabetes can cause damage to your eyes that can lead to poor vision or even blindness. But you can take steps to prevent diabetic eye disease, or keep it from getting worse, by taking care of your diabetes.
The best ways to manage your diabetes and keep your eyes healthy are to
- manage your blood glucose, blood pressure, and cholesterol, sometimes called the diabetes ABCs
- get help to quit smoking if you smoke
- have a dilated eye exam once a year
Often, there are no warning signs of diabetic eye disease or vision loss when damage first develops. A full, dilated eye exam helps your doctor find and treat eye problems early - often before much vision loss can occur.
How does diabetes affect my eyes?
Diabetes affects your eyes when your blood glucose, also called blood sugar, is too high.
In the short term, you are not likely to have vision loss from high blood glucose. People sometimes have blurry vision for a few days or weeks when they're changing their diabetes care plan or medicines. High glucose can change fluid levels or cause swelling in the tissues of your eyes NIH external link that help you to focus, causing blurred vision. This type of blurry vision is temporary and goes away when your glucose level gets closer to normal.
If your blood glucose stays high over time, it can damage the tiny blood vessels in the back of your eyes. This damage can begin during prediabetes, when blood glucose is higher than normal, but not high enough for you to be diagnosed with diabetes. Damaged blood vessels may leak fluid and cause swelling. New, weak blood vessels may also begin to grow. These blood vessels can bleed into the middle part of the eye, lead to scarring, or cause dangerously high pressure inside your eye.
Most serious diabetic eye diseases begin with blood vessel problems. The four eye diseases that can threaten your sight are
Diabetic Retinopathy
The retina NIH external link is the inner lining at the back of each eye. The retina senses light and turns it into signals that your brain decodes, so you can see the world around you. Damaged blood vessels can harm the retina, causing a disease called diabetic retinopathy.
In early diabetic retinopathy, blood vessels can weaken, bulge, or leak into the retina. This stage is called nonproliferative diabetic retinopathy.
If the disease gets worse, some blood vessels close off, which causes new blood vessels to grow, or proliferate, on the surface of the retina. This stage is called proliferative diabetic retinopathy. These abnormal new blood vessels can lead to serious vision problems.
Diabetic macular edema
The part of your retina that you need for reading, driving, and seeing faces is called the macula. Diabetes can lead to swelling in the macula, which is called diabetic macular edema. Over time, this disease can destroy the sharp vision in this part of the eye, leading to partial vision loss or blindness. Macular edema usually develops in people who already have other signs of diabetic retinopathy.
Glaucoma
Glaucoma is a group of eye diseases that can damage the optic nerve - the bundle of nerves that connects the eye to the brain. Diabetes doubles the chances of having glaucoma, which can lead to vision loss and blindness if not treated early.
Cataracts
The lenses within our eyes are clear structures that help provide sharp vision - but they tend to become cloudy as we age. People with diabetes are more likely to develop cloudy lenses, called cataracts. People with diabetes can develop cataracts at an earlier age than people without diabetes. Researchers think that high glucose levels cause deposits to build up in the lenses of your eyes.
How common is diabetic eye disease?
Diabetic retinopathy
About one in three people with diabetes who are older than age 40 already have some signs of diabetic retinopathy. Diabetic retinopathy is the most common cause of vision loss in people with diabetes. Each person's outlook for the future, however, depends in large part on regular care. Finding and treating diabetic retinopathy early can reduce the risk of blindness by 95 percent.
Glaucoma and cataracts
Your chances of developing glaucoma or cataracts are about twice that of someone without diabetes.
Who is more likely to develop diabetic eye disease?
Anyone with diabetes can develop diabetic eye disease. Your risk is greater with
- high blood glucose that is not treated
- high blood pressure that is not treated
High blood cholesterol and smoking may also raise your risk for diabetic eye disease.
Some groups are affected more than others. African Americans, American Indians and Alaska Natives, Hispanics/Latinos, Pacific Islanders, and older adults are at greater risk of losing vision or going blind from diabetes.
If you have diabetes and become pregnant, you can develop eye problems very quickly during your pregnancy. If you already have some diabetic retinopathy, it can get worse during pregnancy. Changes that help your body support a growing baby may put stress on the blood vessels in your eyes. Your health care team will suggest regular eye exams during pregnancy to catch and treat problems early and protect your vision.
Diabetes that occurs only during pregnancy, called gestational diabetes, does not usually cause eye problems. Researchers aren't sure why this is the case.
Your chances of developing diabetic eye disease increase the longer you have diabetes.
What are the symptoms of diabetic eye disease?
Often there are no early symptoms of diabetic eye disease. You may have no pain and no change in your vision as damage begins to grow inside your eyes, particularly with diabetic retinopathy.
When symptoms do occur, they may include
- blurry or wavy vision
- frequently changing vision - sometimes from day to day
- dark areas or vision loss
- poor color vision
- spots or dark strings (also called floaters)
- flashes of light
Talk with your eye doctor if you have any of these symptoms.
When should I see a doctor right away?
Call a doctor right away if you notice sudden changes to your vision, including flashes of light or many more spots (floaters) than usual. You also should see a doctor right away if it looks like a curtain is pulled over your eyes. These changes in your sight can be symptoms of a detached retina NIH external link, which is a medical emergency.
How do doctors diagnose eye problems from diabetes?
Having a full, dilated eye exam is the best way to check for eye problems from diabetes. Your doctor will place drops in your eyes to widen your pupils. This allows the doctor to examine a larger area at the back of each eye, using a special magnifying lens. Your vision will be blurry for a few hours after a dilated exam.
Your doctor will also
- test your vision
- measure the pressure in your eyes
Your doctor may suggest other tests, too, depending on your health history.
Most people with diabetes should see an eye care professional once a year for a complete eye exam. Your own health care team may suggest a different plan, based on your type of diabetes and the time since you were first diagnosed.