Some say that eyes are the windows to the soul. For people with diabetes, the eyes are certainly the windows into your health. Your eyes can be protected or damaged by your blood glucose control, and they’re often a microcosm of your greater diabetes care. Read on for tips on keeping your eyes healthy for years to come.
Keep Your Blood Glucose in Control
You’ll need to keep your blood glucose on target to keep your eyes healthy. Why would blood glucose matter at all to your eyes? Well, your retina contains those all-important specialized cells (rods and cones) that help you see clearly. Blood vessels supply the retina with necessary blood and nutrients to keep those cells in tip-top condition. Blood vessels also supply nerves in your eyes.High blood glucose damages blood vessels and nerves by slowing or lessening the flow of blood. When this happens, the cells in your retina are, in a way, starved of what they need to survive and flourish, leading to eye disease called diabetic retinopathy. High blood glucose can increase your risk for cataracts and nerve damage in your eye.
In the short term, high blood glucose can also lead to blurry vision, a symptom that can prompt a person to see a doctor and lead to a diagnosis of diabetes. Sometimes this might happen if you’re experiencing hyperglycemia (an episode of high blood glucose) or if you’re changing medications. Likely, the blurry vision will go away once your blood glucose returns to normal.
The American Diabetes Association recommends a reasonable goal for many with diabetes of A1C below 7 percent, as well as a fasting blood glucose of 80–130 mg/dL and a blood glucose of less than 180 mg/dL 1–2 hours after meals. Ask your diabetes care provider about your ideal blood glucose and A1C targets.
Lower Your Blood Pressure and Cholesterol
Lowering your blood pressure and cholesterol will help keep the blood vessels in your eyes healthy. High blood pressure and high cholesterol damage blood vessels and nerves by blocking the supply of essential blood and nutrients. Much like high blood glucose, these things can lead to diabetic retinopathy, optic neuropathy, and buildup of fluid in the retina.Your diabetes care team should measure your blood pressure at every checkup. The American Diabetes Association recommends less than 140 mm/Hg systolic blood pressure and less than 90 mm/Hg diastolic blood pressure.
To lower your blood pressure, eat wholesome, nutritious foods that are low in sodium. Exercise regularly and try to lose weight. You may need to take medication, such as ACE inhibitors, angiotensin II receptor blockers (ARBs), and other drugs, to lower your blood pressure.
You should also have your blood lipids (cholesterol and other blood fats) measured at diagnosis and every 5 years after, or as needed. Your diabetes care provider may prescribe medication to lower your bad cholesterol, and you should exercise, eat healthy foods, and lose weight if possible.Stop Smoking or Never Start
Everyone knows that smoking is bad for your health. But did you know smoking can also lead to vision impairment and eye disease? Yep, add your eyesight to the long list of reasons to quit smoking (or never start).Smoking raises your blood pressure, which, as explained in the preceding section, can damage the blood vessels in your eyes. People who smoke have a greater risk for two eye diseases, macular degeneration and cataracts, which can both lead to vision loss including blindness. People with diabetes are at greater risk for glaucoma, cataracts, and other eye diseases, so quitting smoking is a must.
Call 800-QUIT-NOW or visit www.smokefree.gov for resources on quitting smoking.
Be Aware of Major Eye Diseases
Diabetic retinopathy is the number one cause of blindness among working-age adults in the United States. It’s caused by high blood glucose and leads to several changes in your eyeballs. There are two types of diabetic retinopathy:- Background retinopathy: In background retinopathy, tiny blood vessels (called capillaries) rupture and spill blood and fluid. This can lead to scarring and loss of vision. The reduced blood flow can also damage nerve tissue. It can cause diabetic macular edema (DME), swelling of the retina’s macula area that can impair central vision (used for driving, reading, and so on). Injections and laser surgery can be effective treatments (see more about them later in this chapter).
- Proliferative retinopathy: In the more serious proliferative neuropathy, reduced blood flow prompts your body to make more small blood vessels in your eyes. That’s how it gets its name; proliferative means to grow rapidly. However, these new blood vessels are fragile and rupture easily, sometimes leading to a sudden loss of vision or scarring that can lead to a detached retina.
Cataracts are cloudy parts of your lens, which can blur your vision. High blood glucose can cause your lenses to swell and become cloudy, both of which increase your risk for cataracts. People with diabetes are more likely to have cataracts than people without diabetes.
High blood glucose and high blood pressure put your whole body at risk, so if you find out you have eye disease, ask about other potential complications. For example, people with diabetes and severe retinopathy are twice as likely to have coronary heart disease than people without retinopathy. And they have a three times higher risk of it being deadly. People with diabetes and eye disease are also more likely to have kidney disease. (And the opposite is true: People with kidney disease due to diabetes have a very high likelihood of having eye disease as well.)
Get Regular Dilated Eye Exams
A dilated eye exam is the best way to detect and prevent the progression of diabetic eye diseases — and help preserve your vision for years to come. It’s truly your most powerful weapon to keep your eyesight. Many of the eye diseases mentioned in the preceding section can be treated effectively when caught early enough. However, the only way to catch these eye diseases is with a dilated eye exam.Why is a dilated eye exam necessary? You may not notice vision damage before it’s too late. Sometimes there are no warning signs. Yet, an ophthalmologist or optometrist employs specialized tools to look inside your eye — all the way to your retina and optic nerve — to detect changes.
The American Diabetes Association recommends that every person with type 2 diabetes receive a dilated eye exam at diagnosis. Then you should have an eye exam every 1–2 years after, depending on your provider’s recommendation.
In a dilated eye exam, your eye-care provider will dilate your eyes using drops. The drops make your retina big — really big — and allow more light into the back of your eye. This allows your provider to see your whole retina, macula, and optic nerve. She’ll use a special magnifying glass to inspect the blood vessels and other important parts.Tonometry is a fancy name for measuring the pressure in your eye, and it’s used to detect glaucoma. Your eye-care provider will check your peripheral (or side) vision for signs of damage. You’ll also get a vision test to check whether you can see clearly up close or at a distance. This is that black-and-white eye chart with the giant E at the tippy top. You can then be measured for glasses or contact lenses if needed.
Get the Treatment You Need
Blindness can be reduced by 90 percent if diabetic retinopathy is caught early and treated. That’s an amazing number. Injections and laser surgery can treat diabetic retinopathy. For example, anti-VEGF injections can treat diabetic macular edema. Also, a surgical procedure can improve retinal detachment. Cataracts can be treated by replacing the damaged lens with an artificial lens to restore vision. Eye drops can help treat glaucoma, and laser and other types of surgery can be used, too.If your optometrist or ophthalmologist diagnoses eye disease, make sure you schedule treatment even if you don’t feel like there’s anything wrong. You may not have any symptoms or vision problems — and yet you may still need treatment to preserve your vision.
The ACCORD study showed that intensive glucose control can reduce the risk of progression of diabetic retinopathy in people with type 2 diabetes. Keeping your blood glucose on target really does help!
Consider Your Eyes during Pregnancy
You’re focused on the baby growing inside you when you become pregnant — and rightly so. If you had type 2 diabetes before you became pregnant, your diabetes care team is probably working with you to make sure you manage your blood glucose during pregnancy. You’re probably watching what you eat and monitoring your blood glucose more closely. Another thing to keep in mind: your eyes.Diabetic retinopathy can develop and progress rapidly during pregnancy for women with preexisting type 2 diabetes. Sometimes this coincides with the more intensive blood glucose management that is recommended during pregnancy.
If you have type 2 diabetes, the American Diabetes Association recommends a dilated exam before you become pregnant or during your first trimester. Then have an eye exam during each trimester and the year following your baby’s birth.
Assess Your Risk Factors
Hispanic Americans are more likely to have diabetic retinopathy than people of other races. Also, a family history of glaucoma is a risk factor for this type of eye disease.Adolescents with type 2 diabetes are more likely to develop retinopathy than adolescents with type 1 diabetes — and perhaps with more severity. One study found that most kids with type 2 diabetes don’t get eye exams despite health insurance coverage, even within 6 years of diagnosis.
The number of Americans with diabetic retinopathy is expected to double from 2010 to 2050, going from 7.7 million to 14.6 million, according to the National Institutes of Health’s National Eye Institute.