Over time, high blood sugar levels from diabetes may cause inflammation of the eye’s blood vessels. This inflammation can gradually cause further damage, leading to permanent blindness in severe cases.
However, treatment and management approaches for diabetes can help prevent or limit serious eye problems. Also, not everyone with diabetes will experience eye problems or vision loss.
Talk with a doctor for personal advice about diabetes and eye health.
Read on to learn more about how diabetes may affect the eyes, and how to prevent damage.
With diabetic retinopathy, high blood sugar levels cause inflammation and damage the eye’s blood vessels over time. The retina is a tissue at the back of the eye that helps process light and images.
The damaged blood vessels can form tiny bulges, or microaneurysms, and leak blood or fluids. This can lead to retinal swelling, lesions, and swelling in the eye’s macula, or diabetic macular edema.
At more advanced stages, new, fragile blood vessels may grow and leak more blood, causing scar tissue to form.
Eventually, diabetic retinopathy may lead to retinal detachment and permanent vision loss. However, early treatment can help reverse, prevent, or slow damage.
Learn more about diabetic retinopathy, including its stages, treatment, and outlook.
The early stages of diabetic retinopathy do not usually cause noticeable symptoms. Symptoms may appear when the condition is more advanced, and can include:
- floaters, shapes that appear to float across the vision
- blurry vision
- blank or dark spots in the vision
- difficulty seeing in low lighting
- seeing colors as more faded or washed out
- generally worsening vision, such as noticing more difficulty seeing when driving or reading
Often, symptoms affect both eyes. However, diabetic eye conditions sometimes affect one eye only or progress in different stages in each eye.
Regular eye checkups are essential with diabetes
Many eye conditions linked to diabetes do not cause symptoms until severe damage has developed. As a result, sometimes only an eye doctor can spot eye conditions at early stages. This is when treatment may be more effective.
Talk with a doctor about how often you should have a comprehensive eye exam. This can vary per person and depending on your health.
Glaucoma is a group of eye conditions that damage the optic nerve and can cause vision loss. Glaucoma develops when the fluid in the eye cannot drain properly, causing pressure to build up.
The National Institutes of Health (NIH) states that people with diabetes are about twice as likely to develop glaucoma or cataracts as people without diabetes.
Diabetes may cause different types of glaucoma, including:
- open-angle glaucoma
- neovascular glaucoma, whereby diabetic retinopathy causes new blood vessels to grow and block the eye’s drainage
- steroid-induced glaucoma, whereby steroid medications for diabetic retinopathy contribute to glaucoma
Read more about the types of glaucoma.
Like some other eye conditions, glaucoma does not usually cause noticeable symptoms at first.
Depending on the type of glaucoma, the following symptoms may appear over time:
- gradual vision loss, particularly affecting side or peripheral vision
- blurry vision or blind spots
- eye pain or redness
- cloudy eyes
- light sensitivity
- vision appearing dim, as if there were not enough light
- production of more tears
Sometimes, glaucoma may cause sudden symptoms.
Learn about glaucoma treatment and outlook.
A cataract is a clouding of the lens at the front of the eye.
High blood sugar levels from diabetes can cause the fluid in the front of the eye, the aqueous humor, to become high in sugar as well. This can lead to swelling and protein buildup in the eye’s lens, causing cloudiness.
Read more about cataracts, including their treatment and prevention.
Cataracts may cause more noticeable symptoms as they advance, such as:
- cloudy or blurry vision
- colors appearing faded
- difficulty seeing in low lighting
- finding sources of light too bright
- seeing halos or rings around lights
- double vision
- frequently having to change your glasses or contact lens prescription
Eventually, you may be able to see yellowish discoloration in the eye.
Preventing diabetic eye disease
The following steps may help reduce the risk of vision loss with diabetes:
- getting a comprehensive dilated eye exam at least once per year, more often if your doctor recommends it
- keeping blood sugar levels within your target range
- keeping cholesterol and blood pressure ranges within target ranges
- not smoking
- getting regular physical activity
- following your treatment plan as prescribed by your medical team
- contacting a doctor as soon as possible for new or persistent symptoms
Talk with your doctor for personal advice about diabetes management, blood pressure, and cholesterol.
Read more about diabetes treatment options.
High blood sugar levels from diabetes sometimes cause eye conditions such as diabetic retinopathy, glaucoma, and cataracts.
Often, diabetes-related eye conditions do not cause noticeable symptoms until they are advanced. As a result, regular eye exams are key in preventing vision loss if you have diabetes.
Diabetes treatment and management can help reduce or prevent eye damage from diabetes.
Contact an eye doctor promptly if you notice vision symptoms or have questions about your eye health.