Complications of Diabetes
Complications of diabetes can damage kidneys, eyes, your heart, and more. Keeping your blood sugar well controlled lowers your risk of diabetes complications.
More than 30 million Americans have diabetes, and one in four of them don’t know it. What’s more, another 96 million adults in the U.S. have prediabetes, marked by blood sugar levels higher than normal but not yet in the diabetes range — and 90 percent of these people are clueless they have this condition, too, according to the Centers for Disease Control and Prevention (CDC). These statistics are worrisome because diabetes, and the complications of diabetes, are serious health concerns.
That’s why it’s important to have regular check-ups. If are diagnosed with diabetes, or prediabetes, you should take your condition seriously and work with your doctor keep your blood sugar (also called blood glucose) under control to help prevent complications of diabetes — including some that can be life-threatening.
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What causes diabetes complications?
There are two types of chronic diabetes, type 1 and type 2. Around 95 percent of Americans diagnosed with diabetes have type 2, primarily caused by lack of exercise and being overweight or obese, according to the CDC.
The pancreas normally produces the hormone insulin, which allows glucose to enter your cells. But in type 2 diabetes, cells don’t respond properly to insulin, causing glucose to build up in your blood. Type 1 diabetes is believed to be an autoimmune condition that prevents the pancreas from producing adequate, or any, insulin to regulate blood sugar.
Gestational diabetes is another type of diabetes, but it is usually not chronic. It occurs only during pregnancy and often resolves after childbirth. Uncontrolled high blood sugar during pregnancy, however, can cause health problems in mothers and their babies. Preeclampsia is a complication of gestational diabetes characterized by high blood pressure, excess protein in the urine, and swelling in the legs. If severe and not treated promptly, preeclampsia can threaten the lives of expectant mothers and their babies.
No matter what kind of diabetes you have, the result is excess blood sugar. And without strict control, elevated glucose can lead to many diabetes complications, the CDC warns.
Nerve damage caused by diabetes is common
High levels of blood sugar in the blood of people with diabetes frequently cause nerve damage. Diabetic neuropathy, the medical term for this condition, leads to symptoms in different parts of your body, depending on the type of nerve damage.
The most common type of nerve damage is peripheral neuropathy and it affects close to one-half of people with diabetes, according to the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). Peripheral neuropathy causes burning, tingling, numbness, pain, and weakness primarily in your feet and legs, but it may also affect your hands and arms,
Other types of diabetic neuropathy include:
- Autonomic neuropathy — damage to nerves controlling your internal organs. This diabetes complication can cause abnormalities with blood pressure, heart rate, your digestive system, sex organs, bladder, eyes, and sweat glands.
- Focal neuropathy — damage to single nerves, most often in your hand, head, torso, or leg, causing pain, tingling, burning, and sometimes weakness.
- Proximal neuropathy — nerve damage in your hip, buttock, or thigh. An uncommon type of diabetic neuropathy, it typically affects only one side of your body but may spread to the other side.
Be aware of these serious complications of diabetes
Over time, if blood sugar levels remain too high, damage to blood vessels, as well as nerves, occurs. That damage can lead to heart disease, stroke, and even blindness. In fact, seven in 10 people with diabetes who are over 65 will die from a heart attack or another type of cardiovascular disease — and one in six will die from stroke.
Elevated glucose levels can also cause kidney disease (nephropathy). Parts of tiny blood vessels that normally filter metabolic wastes begin to leak, releasing small amounts of protein into the urine. Without early treatment to lower blood sugar and treat the resulting kidney disease, the kidneys dump increasing amounts of protein, and waste products build up in your blood. Eventually, your kidneys can fail, resulting in the need for dialysis or a kidney transplant.
Diabetic eye disease is a group of eye problems (diabetic retinopathy, diabetic macular edema, cataracts, and glaucoma) that can affect people with diabetes — especially if you have high blood sugar and elevated blood pressure and cholesterol levels, according to the NIDDK. Over time, high blood sugar damages tiny blood vessels in the back of your eyes, causing swelling and scarring. The most serious diabetic eye complications start with these blood vessel problems and, if untreated, can damage sight and even cause blindness.
Diabetic retinopathy is the most common cause of vision loss in people with diabetes. In early diabetic retinopathy, blood vessels bulge, weaken, or leak into your retina (the light-sensitive tissue lining the back of your eye). Without treatment, the disease worsens, some blood vessels close off, and others begin growing on the surface of the retina. This stage, called proliferative diabetic retinopathy, can cause serious vision problems and even blindness. If diabetic retinopathy is diagnosed and treated at an early stage, however, the risk of blindness is reduced by 95 percent.
Hyperosmolar hyperglycemic nonketotic syndrome (HHNS) is a potentially life-threatening complication of diabetes in which blood sugars rise to extremely high levels, causing excessive urination and dehydration. Without medical care, HHNS can lead to seizures, coma, and death, according to the American Diabetes Association. This serious complication of diabetes can take days or weeks to develop and is more likely to occur in older people with diabetes who are suffering from an illness or infection and whose blood sugar is not controlled properly.
More complications of diabetes
- Amputations: Diabetes-related damage to blood vessels and nerves, especially in your feet, can lead to serious, hard-to-treat infections, sometimes necessitating amputation.
- Bladder problems. Blood vessels and nerves damaged by high blood sugar are associated with urine retention and leakage. People with diabetes are also at increased risk for bladder and kidney infections.
- Sexual problems. Changes in your blood vessels, nerves, and hormones associated with diabetes can make it more difficult for you to have satisfactory sex. More than half of men with diabetes experience erectile dysfunction over time. Vaginal dryness and painful sex caused by nerve damage can also affect women’s sex lives.
- Gum disease. Diabetes increases the risk of gum disease and tooth loss.
- Gastroparesis. Also called delayed gastric emptying, gastroparesis is caused by diabetes damage to the vagus nerve. This results in stomach and intestinal muscles failing to work properly and the flow of food slows or stops. Symptoms include nausea, bloating, heartburn, weight loss, and vomiting.
Good news about diabetes complications
Although diabetes affects millions of Americans and complications of diabetes take a heavy toll both on individuals and the U.S. healthcare system, the CDC reports people with type 1 and type 2 diabetes are living healthier, longer lives, compared to 20 years ago. Early diagnosis and treatment of both diabetes and accompanying health problems, such as high blood pressure and elevated cholesterol, have reduced rates of major complications — especially stroke and heart attacks.
If you have diabetes, or have been diagnosed with prediabetes, keeping your blood sugar under control can help you stay as healthy as possible.
- Work with your doctor on a treatment plan for a healthy lifestyle (including exercise and weight control).
- Stick to regular doctor appointments.
- Take your medicines exactly as prescribed.
- Carefully monitor your blood sugar levels.
Being proactive is an important factor for reducing diabetes complications — and living your healthiest life possible.
Updated:  
February 17, 2023
Reviewed By:  
Janet O’Dell, RN