Diabetes | Complications


Learn More About Diabetes Complications

Diabetes and Heart Disease

What are diabetic complications?

Too much glucose in the blood can lead to serious health problems, including heart disease and damage to the nerves and kidneys. These are known as diabetic complications.

Diabetic Neuropathy (nerve damage)

Diabetic neuropathy makes it hard for your nerves to send messages to the brain and other parts of the body. If you have nerve damage, you may lose feeling in parts of your body or have a painful, tingling or burning feeling.

Neuropathy most often affects the feet and legs. If you have neuropathy, you may not be able to feel a sore on your foot. The sore can become infected and, in serious cases, the foot may have to be amputated (removed). People who have neuropathy may continue walking on a foot that has damaged joints or bones. This can lead to a condition called Charcot foot that causes swelling and instability in the injured foot. It can also cause the foot to become deformed. However, this problem can often be avoided.

If you have diabetes, check your feet every day. If you see swelling, redness and feel warmth in your foot, see your doctor immediately. These can be signs of Charcot foot. Your doctor should also check your feet frequently.

Warning signs of nerve damage

Call your doctor if you have:

  • Numbness, tingling or burning feelings in your fingers, toes, hands and/or feet
  • Sharp pain that is worse at night
  • Cuts, sores or blisters on your feet that don't hurt as much as you would expect, and that also heal very slowly
  • Muscle weakness and difficulty walking

Erectile dysfunction (in men) and vaginal dryness (in women)

Diabetic Retinopathy (eye problems)

The retina is the part of the eye that is sensitive to light and sends messages to your brain about what you see. Diabetes can damage and weaken the small blood vessels in the retina. This damage is called diabetic retinopathy.

When the blood vessels of your retina are damaged, fluid can leak from them and cause swelling in your macula. The macula is the central part of the retina and give you sharp, clear vision. The swelling and fluid can cause blurry vision and make it hard for you to see. If retinopathy gets worse, it may lead to blindness.

Laser surgery can often be used to treat or slow down retinopathy, especially if the problem is found early. People who have diabetes should have an eye exam once a year.

Warning signs of eye problems

Call your doctor if you have:

  • Blurry vision for more than 2 days
  • Sudden loss of vision in 1 or both eyes
  • Black or gray spots, cobwebs or strings that move or drift when you move your eyes (called floaters)
  • Flashing lights in your vision that aren't really there
  • Pain or pressure in your eye(s)

Diabetic Nephropathy (kidney damage)

Diabetes can also damage the blood vessels in your kidneys so they can't filter out waste. This damage is called diabetic nephropathy. Some people who have nephropathy will eventually need dialysis (a treatment that eliminates waste from the blood) or kidney transplant.

The risk for nephropathy is increased if you have both diabetes and high blood pressure, so it is important to control both of these conditions.

Protein in the urine is usually the first sign of nephropathy. This should be checked yearly.

Heart Disease and Stroke

People who have diabetes are at greater risk for heart disease and stroke. The risk is even greater for people who have diabetes and smoke, have high blood pressure, have a family history of heart disease or are overweight.

Heart disease is easiest to treat when it is caught early. It is very important to see your doctor on a regular basis. He or she can test for early signs of heart disease.

The recommended cholesterol level for a person who has diabetes is the same as for someone who has heart disease. If your cholesterol is higher than the recommended level, your doctor will talk to you about lifestyle changes and medication to help get your cholesterol under control.

What can I do to prevent or delay diabetic complications?

To prevent problems, keep your blood sugar level as close to normal as possible and follow your doctor's instructions. The following are some other tips:

  • Carefully follow your doctor's instructions for taking your insulin.
  • Eat a variety of healthy foods. Avoid foods that are high in fat, cholesterol, salt and added sugar.
  • Maintain a healthy weight. If you're overweight, your doctor can give you advice on how to lose weight safely.
  • Keep your blood pressure at a healthy level (below 130/80 mm Hg).
  • Maintain a healthy cholesterol level (under 200 mg).
  • Be physically active on a regular basis.
  • Quit smoking.
  • Take care of your feet and check them every day for signs of injury and infection.
  • Have an eye exam every year to check your vision.
  • See your dentist twice a year to check your teeth and gums.
  • Stay up-to-date on your immunizations. Get a flu shot each year and a tetanus booster every 10 years.
  • Manage your stress.
  • See your doctor regularly, even when you feel fine. Your doctor will check for early signs of complications.
  • Call your doctor right away if you have any of the warning signs listed.


See a list of resources used in the development of this information.

Portions of this article were developed by the American Academy of Family Physicians in cooperation with the American Diabetes Association.

Portions of this article were developed as part of an educational program made possible by an unrestricted educational grant from LifeScan, Inc., makers of OneTouch Blood Glucose Meters.

Portions of this article were developed with general underwriting support from The Coca-Cola Company.

Written by familydoctor.org editorial staff

Reviewed/Updated: 05/14
Created: 01/99

Learn More About Diabetes Complications

Diabetes and Heart Disease