The leading causes of chronic kidney disease (CKD) are diabetes and high blood pressure. These conditions are also the leading causes of eye disease and loss of vision. If your renal disease is a result of either condition your vision may be at risk. Diabetes and high blood pressure often go undiagnosed because people don’t notice any symptoms. As time goes on without medical treatment, these conditions can worsen and other complications—such as kidney disease and eye problems—arise.
If you have chronic kidney disease not due to high blood pressure you may still want to monitor your blood pressure regularly, as kidney disease can cause high blood pressure and put your vision at risk.
Some of the most common eye problems that occur in CKD patients are retinopathy, cataracts and glaucoma.
Retinopathy is a condition where the small blood vessels in the eyes become damaged as a result of high blood pressure or diabetes. When the damage is caused by diabetes, it is called diabetic retinopathy.
Diabetes elevates the blood glucose levels in the bloodstream. These high glucose levels can damage the tiny blood vessels in the kidneys, fingers feet and eyes. High blood pressure places strain on the walls of the blood vessels, weakening them to the point where they can break or burst. Like chronic kidney disease, both types of retinopathy occur over time and symptoms are often not felt until the damage is done.
The affected area of the eye is called the retina. The retina, which senses light, is a thin layer of blood vessels and nerve endings that cover the back of the eye. When these blood vessels become damaged, they weaken and break. Blood leaks into the vitreous, which is the clear, jelly-like substance that fills the inside of the eye. When too much blood leaks into the vitreous it will become cloudy, preventing light from reaching the retina.
Damaged vessels are replaced by new ones, but these are also weak and can break. As more blood leaks into the vitreous, even less light reaches the retina. Sometimes the vessels become so damaged scar tissue forms. This scar tissue can fall away from the back of the eye, taking the retina with it. This condition is known as a detached retina. A detached retina can cause severe loss of sight or blindness and should be treated by a medical professional right away.
Cataracts occur when the lens of your eye becomes cloudy. The lens of the eye is normally clear. Its purpose is to focus the light coming in from the pupil to the retina at the back of the eye. A cataract scatters the incoming light and can make everything look blurry.
Cataracts develop as we age. But patients with diabetes are at a higher risk for cataracts. Diabetics can develop what is known as “sugar cataracts,” a cataract that appears suddenly and grows to such a point that the entire lens is clouded. High levels of glucose react with proteins found in the eye and form a byproduct that settles on the lens.
Glaucoma affects the optic nerve at the back of the eye. The optic nerve sends impulses to the brain, and the brain translates these impulses into images. When too much pressure builds up in the eye, the optic nerve can become damaged. This damage could lead to partial or total vision loss.
Increased pressure occurs when the clear fluid inside the eye (called the aqueous humor) does not drain properly. This pressure pushes against the blood vessels which supply the optic nerve with oxygen and nutrients. Over time the nerves are starved of these essentials and die. As the nerves die, there is a gradual loss of peripheral vision.
High blood pressure and diabetes are possible risk factors for glaucoma.
When you have an eye exam, your eye doctor (either an optometrist, who is a doctor of optometry or an ophthalmologist, who is a medical doctor that specializes in eyes) will check your vision as well as the health of your eyes. Your eye doctor will look inside your eye by dilating your pupils with special drops and using different equipment. By peering into the eye, your doctor can look at the blood vessels inside your eye to determine whether or not they are healthy. Your doctor will also perform a glaucoma test by testing your peripheral (side) vision and eye pressure.
If anything abnormal is found, your eye doctor may refer you to your primary doctor. If your eye doctor is an optometrist, you may be sent to an ophthalmologist. Tell your doctors and members of your healthcare team right away if you notice any changes in your vision such as:
Regular eye exams are important to monitor the health of your eyes. People with diabetes are encouraged to get a yearly eye exam.
Managing conditions such as high blood pressure or diabetes is important not only for the health of your kidneys, but also the health of your eyes. Follow your doctor’s instructions regarding diet and exercise, take your prescribed medicines and check your glucose levels or blood pressure as recommended by your doctor. If you smoke, your doctor may ask you to quit. Smoking is an added risk factor for cataracts and glaucoma.
Vision problems can be a serious complication of diabetes and high blood pressure. Patients who develop renal disease as a result of these conditions should be aware that their eyes are at risk. Managing these conditions can prevent further damage to your eyes as well as help you manage your chronic kidney disease.
This site is for informational purposes only and is not intended to be a substitute for medical advice from a physician.
Please check with a physician if you need a diagnosis and/or for treatments as well as information regarding your specific condition. If you are experiencing urgent medical conditions, call 9-1-1