People with diabetes are at risk of a variety of eye diseases. The American Academy of Ophthalmology refers to diabetes-related eye problems under the umbrella term “diabetic eye disease.” Some conditions that are considered types of diabetic eye disease include:

• Glaucoma
• Diabetic retinopathy
• Diabetic macular edema
• Cataracts

If you’re living with diabetes, it’s important to tell your doctor about any new or worsening eye symptoms. Regular eye exams can help ensure that you get early treatment in case an eye condition develops. Here’s more information about diabetic eye diseases that you can discuss with your diabetes care team.

1. Glaucoma

Glaucoma is the second most common cause of blindness among adults in the United States, according to the American Optometric Association. This disease is the result of a process that involves:

• Fluid buildup in the eye
• High eye pressure
• Optic nerve damage

Your eye is always making a fluid called aqueous humor, which provides nutrients to the eye and maintains its shape. Aqueous humor needs to drain out to make room for newly produced aqueous humor. Otherwise, this fluid builds up and causes greater pressure in your eye.

High eye pressure can damage the optic nerve. This nerve in the back of the eye is directly connected to the brain. When light reaches the retina (the lining on the inside of the back of your eye), it sends signals via the optic nerve to the part of the brain that’s responsible for eyesight.

Damaged optic nerve fibers can’t communicate with the brain very well. This results in blind spots that you don’t notice at first. Vision loss increases as more optic nerve fibers are damaged and can lead to complete blindness.

Vision problems from glaucoma are permanent. However, with early detection, prompt treatments can keep it from getting worse and preserve the vision you have. If you’re living with diabetes, frequent and thorough eye exams are essential for detecting glaucoma in its early stages.

Types of Glaucoma Most Commonly Linked to Diabetes

There are many types of glaucoma. Diabetes increases the risk of these three types:

• Primary open-angle glaucoma — Occurs more commonly than other types among people with diabetes, particularly type 2 diabetes
• Steroid-induced glaucoma — Can occur in people who take steroid eye drops or receive injections for other eye problems
• Neovascular glaucoma — Develops in people with diabetic retinopathy and causes blood vessels to grow abnormally, blocking the drainage of the aqueous humor

Glaucoma Diagnosis

Glaucoma doesn’t cause symptoms in the early stages. An ophthalmologist (eye doctor) can detect the condition with a complete eye exam. A more limited exam that tests only eye pressure may not reveal glaucoma. A complete glaucoma exam includes:

• Checking eye drainage
• Testing peripheral (side) vision
• Taking pictures of the optic nerve

2. Diabetic Retinopathy

The retina contains specialized cells that detect light and send signals to the brain, making vision possible. “Retinopathy” means “disease of the retina.” In people with diabetic retinopathy, high glucose (blood sugar) levels can damage the retina’s tiny blood vessels. High blood glucose can cause blood vessels to leak, swell, or close off, preventing oxygen and nutrients from reaching the retina.

Types of Diabetic Retinopathy

There are two types of diabetic retinopathy — nonproliferative diabetic retinopathy (NPDR) and proliferative diabetic retinopathy (PDR).

The nonproliferative type is early-stage retinopathy and is common in people with diabetes. In NPDR, retinal blood vessels damaged by high blood sugar may eventually close off. This may cause blurred vision, but mild symptoms don’t always require treatment.

The proliferative type is late-stage diabetic retinopathy and is a serious condition. In PDR, the retina forms abnormal blood vessels. These new blood vessels can bleed into an area in the middle of the eye called the vitreous humor. People with PDR may notice floaters (shadowy specks moving in the eye) or loss of vision due to this bleeding. The abnormal blood vessels can also form scar tissue that may pull on the retina, causing it to detach. If not treated, this condition can cause permanent, severe vision loss.

What Are the Stages of Diabetic Retinopathy?

Doctors often describe diabetic retinopathy in four stages: mild, moderate, and severe NPDR, followed by PDR. Each stage reflects how much damage has happened in the retina. PDR is the most advanced and most likely to cause vision loss.

Treatment for Diabetic Retinopathy

Treatments for NPDR and PDR include:

• Steroid injections or implants to reduce swelling
• Anti-vascular endothelial growth factor (anti-VEGF) injections to stop the growth of abnormal blood vessels and reduce swelling
• Continuous anti‑VEGF delivery implant, which slowly releases medicine over months, so some people may need fewer treatments compared with monthly shots
• Laser treatments to close leaky blood vessels, as well as to shrink abnormal new blood vessels and prevent them from growing
• Vitrectomy, an eye surgery that removes scar tissue and blood from the eye

3. Diabetic Macular Edema

Some people with diabetic retinopathy develop diabetic macular edema, which affects a part of the retina called the macula. The macula is in the center of the retina and is responsible for central vision. Damage to the macula makes recognizing faces and reading difficult.

Fluid from leaky blood vessels caused by diabetic retinopathy can build up in the macula and cause it to swell. “Edema” is the medical term for “swelling due to fluid buildup.”

People with diabetes need regular eye exams to check for macular edema. Diabetic macular edema is the leading cause of vision loss among people with diabetic retinopathy. It’s important to work with your doctor and stick to a treatment plan to prevent vision loss.

People with diabetes need regular eye exams to check for macular edema, which is the leading cause of vision loss among people with diabetic retinopathy.

4. Cataracts

A cataract is a clouding of the eye’s lens — the clear structure behind the iris (the colored part of the eye) that helps focus light for sharp vision. Cataracts usually develop slowly as people age. However, people with diabetes can develop cataracts faster and at younger ages.

High blood sugar levels can cause changes in the lens and lead to clouding. People with cataracts may first notice blurred vision. Cataracts may also give bright colors a dull or yellow hue. Cataracts that affect the entire lens can lead to blindness.

People with diabetes can develop cataracts faster and at younger ages.

Eyeglasses can treat some vision problems caused by cataracts. However, if cataracts affect your quality of life, you can ask your eye doctor about cataract surgery. During this procedure, the cloudy lens is removed and replaced with an artificial lens.

5. Retinal Vein Occlusion

Diabetes increases the risk of retinal vein occlusion, which occurs when the veins that carry blood away from the retina become blocked. Symptoms include blurry vision and, in severe cases, the inability to see out of one eye, either suddenly or over the course of a few days.

It’s important to contact your eye doctor immediately if you develop these symptoms — untreated retinal vein occlusion can lead to vision loss.

6. Dry Eye Syndrome

About 54 percent of people with diabetes develop dry eye syndrome, also known as dry eye disease and keratoconjunctivitis sicca. Dry eye syndrome can be a serious complication because the eyes require constant tear production to stay moist and function properly. Dry eye syndrome is also often linked to other conditions that affect the eyes.

About 54 percent of people with diabetes develop dry eye syndrome.

Dry eye syndrome can occur with diabetes because low insulin levels can lead to less tear production. High blood sugar can damage the nerves that control tear production and blood flow to the eyes, both of which help keep eyes moist. Diabetes-related inflammation may also affect the lacrimal gland, which makes tears, and the eyelid glands that produce oils to keep tears from drying up too quickly.

Symptoms of dry eye syndrome include:

• Persistent burning, stinging, or discomfort, especially when wearing contact lenses
• Eye redness
• Mucus buildup in the eyes
• Blurry vision
• Heightened sensitivity to environmental factors such as wind and smoke
• Excessive tearing (a reaction to dryness)

Treatment options include different types of eye drops and managing the underlying causes of dry eye syndrome, such as high blood pressure and high blood sugar.

7. Double Vision

Diabetes can cause damage to cranial nerves, which control the muscles responsible for eye movement, potentially leading to double vision. Cranial nerves originate in the brain and manage various functions in the head and face, including those related to sight. Double vision from nerve damage is uncommon. It happens in fewer than 1 in 100 people with diabetes, but the risk is 4 to 7 times higher than in people without diabetes.

This kind of double vision often improves on its own within a few months. However, prism lenses, which are added to eyeglasses, can help manage the symptoms. In some cases, surgery may be recommended if the condition doesn’t resolve naturally.

Follow Up With Your Eye Doctor

Researchers and doctors recommend that people diagnosed with type 2 diabetes schedule an eye care appointment right away to look for early signs of diabetic eye disease.

Your eye doctor can help you set up follow-up exams depending on your eye health. Always report any vision changes, and make sure to go to an eye specialist if you’re referred to one. Most eye problems due to diabetes can be treated if found early, and prompt treatment can prevent you from losing your vision.

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