How Can You Die From Untreated Diabetes?

Diabetes can increase the risk of other health problems, but people can also live with it for many years.

Diabetes is a chronic condition that affects millions of people in the United States. Roughly one in 10 people have diabetes in the U.S.—and one in five people don't even know they have it. Untreated diabetes can lead to dangerous health effects that can include death. However, people can live for many years with proper diabetes treatments.

Before insulin was discovered, people with diabetes were living shorter lives. Now, treatments are allowing people with diabetes to live longer lives with good quality of life. Still, diabetes was the seventh leading cause of death in the U.S. in 2021. But what, exactly, causes complications, and what can be done to prevent them?

To find out more, Health spoke with Donald McClain, MD, professor of endocrinology and metabolism at Wake Forest School of Medicine in North Carolina. Here is more information about diabetes, some common but dangerous complications of diabetes, and how people with diabetes can protect themselves.

What Is Diabetes?

Diabetes occurs when your body cannot regulate blood sugar levels. Two types of diabetes exist: type 1 and type 2. Type 1 diabetes prevents you from making insulin, a hormone that controls blood sugar. Type 2 diabetes doesn't make or use insulin well which prevents you from keeping your blood sugar at a normal level. Both conditions can lead to high blood sugar.

Symptoms of diabetes can include:

  • Feeling more thirsty than normal
  • Urinating more than normal
  • Increased hunger
  • Fatigue
  • Blurred vision
  • Numbness or tingling in your hands or feet
  • Sores that don't heal
  • Unexplained weight loss

Diabetes affects the body in many different ways. That's why, if left untreated, it can lead to a variety of complications.

What Are the Complications of Diabetes?

Untreated diabetes can lead to several health complications like diabetic ketoacidosis, nerve damage, kidney problems, heart disease, stroke, and negative impacts on mental health—all due to unregulated high blood sugar.

Chemicals in Your Blood (Diabetic Ketoacidosis)

When diabetes is well managed, patients can live long and healthy lives. However, untreated diabetes can lead to high blood sugar and diabetic ketoacidosis, a serious condition that can be deadly.

Diabetic ketoacidosis occurs when people with diabetes cannot use their blood sugar for energy. Your body's cells normally use sugar for energy, but they require insulin signals to get that sugar from the blood. Without insulin, people with diabetes have to use fat for energy, creating harmful amounts of chemicals called ketones. This complication is more common in people with type 1 diabetes but can also occur in people with type 2 diabetes.

Some symptoms of diabetic ketoacidosis include:

  • Feeling thirsty
  • Urinating frequently
  • Nausea and vomiting
  • Difficulty breathing
  • Weakness
  • Confusion
  • Fruity-smelling breath

Despite treatments for diabetes, ketoacidosis can still happen—and without immediate insulin injections, it can be fatal. This can happen when people skip doses of insulin but can also be caused by illnesses or certain medications. Keep tabs on your blood sugar regularly so you can make sure it stays in the target range. This is especially important if you're sick when you may not be drinking enough fluids or eating enough.

If you suspect you have diabetic ketoacidosis, contact a healthcare provider and get immediate medical help.

Nerve Damage

High blood sugar levels don't just damage organs and blood vessels over time. They can also cause nerve damage, a condition called diabetic neuropathy. Damaged nerves can cause a range of problems from mild numbness to pain that interferes with normal activities. If you have nerve damage in your foot, for example, you may not even feel a cut or sore.

A cut or sore on the foot that is left untreated can lead to serious problems like infection, ulcers, or amputation of the feet or legs. People with diabetes should get in a habit of checking their feet every day. Things to look for are:

  • Cuts
  • Sores
  • Blisters
  • Swelling
  • Skin and nail changes
  • Changes in color or temperature of your feet

If you spot a cut or sore that is infected or isn't healing properly, it's time to get medical attention.

Kidney Problems

Diabetes can cause damage to the organs and tissues in the body over time. "For example, the blood vessels in the kidneys can be damaged by high blood sugar," said Dr. McClain—a complication that can lead to chronic kidney disease and ultimately, kidney failure.

One in three adults with diabetes will develop chronic kidney disease (CKD). Most people who have CKD don't know they have it until the disease has advanced to the point of needing dialysis or a kidney transplant. Chronic kidney disease is separated by stages, the last of which is kidney failure, meaning that your kidney function has dropped below 15% of normal. Diabetes is the number one cause of kidney failure.

Heart and Blood Vessel Problems

People with diabetes have a high risk for heart disease because high blood sugar can damage your heart and blood vessels. People who have Type 2 diabetes are two times more likely to die from heart disease. People with diabetes more often have:

  • Obesity
  • High cholesterol
  • High blood pressure

These conditions can also damage or harden your blood vessels and heart, increasing your risk for heart disease. And the nerves that control your heart can also become damaged.

Maintaining a healthy weight, eating a balanced diet, and getting regular physical activity are all ways people with diabetes can help protect their hearts and brains as they age. Also, make sure to work with your healthcare provider to monitor your blood sugar, blood pressure, and cholesterol.

Low Blood Sugar

Over treatment of diabetes can also harm your health. "If you take too much insulin and your blood sugar goes way down, that can cause seizure, coma, and death," Dr. McClain said. Low blood sugar can starve the brain of oxygen, Dr. McClain added, and it can also trigger irregular heartbeats. These irregular heartbeats increase your risk for strokes or heart attacks.

Improvements in medical technology have made over treatment much less likely than it once was, but it's still a risk—especially as patients get older. "The warning system that lets your brain know that your blood sugar is getting too low becomes blunted as you age," Dr. McClain said. You may not feel the symptoms of low blood sugar when you get older. Medically, this is called hypoglycemia unawareness.

Some mild symptoms of low blood sugar can include:

  • Shakiness
  • Sweating
  • Feeling irritated
  • Feeling nervous or anxious
  • Confusion
  • Lightheadedness or dizziness
  • Nausea
  • Fatigue
  • Headache

If you have low blood sugar, the American Diabetes Association recommends taking 15 grams of carbohydrates every 15 minutes until your blood sugar levels are at least 70 mg/dL. In severe cases, people with low blood sugar may need to be treated with a hormone called glucagon that raises blood sugar.

Impacts on Mental Health

People with diabetes can be affected by several mental health problems. They are two to three times more likely to develop depression than those without diabetes. And they are 20% more likely to have anxiety at some point.

Mental health problems can affect how well you take care of yourself and, therefore, how well you are managing your diabetes. For example, if you're stressed, stress hormones can make blood sugar levels increase. And if you're depressed, you may not be managing your diabetes as well as you could.

There is also something called diabetes distress. This is stress that comes from managing diabetes on a daily basis. Part of that stress comes from having to monitor blood sugar multiple times a day. And another part can come from high medical bills. People with diabetes have more than double the healthcare costs compared to people without diabetes.

If you notice any signs of depression or anxiety, don't ignore them. Talk to a healthcare provider and/or join a support group for people with diabetes.

How Is Diabetes Treated?

"We know that keeping blood sugar under control, for both type 1 and type 2 diabetes, is one of the best ways to reduce the risk of these complications," Dr. McClain said. Diabetes treatments prevent high blood sugar and diabetic ketoacidosis by ensuring the cells can take sugar from the blood.

Most people with type 1 diabetes can use an insulin pump or manually inject themselves with insulin several times a day. Meanwhile, people with type 2 diabetes can make lifestyle changes, take medications, or use insulin—depending on their case. If you have diabetes, ask a healthcare provider which approach is the best for you.

For people with type 2 diabetes, sometimes they need insulin injections to control their blood sugar. insulin can be helpful for people with more severe diabetes who do not respond strongly enough to the levels of insulin their body makes. However, not all people with diabetes need insulin injections. Talk to a healthcare provider about the best way to control your blood sugar.

Healthcare providers are getting better at treating diabetes and preventing complications so patients can live longer, healthier lives. "I had several diabetes patients in their 80s who are doing quite well," Dr. McClain said. "It's not easy, and it's a lot of work on the part of the patient, but we have good tools that are getting better all the time, and we can do this."

A Quick Review

Both high and low blood sugar can lead to serious health complications, including death, in people with untreated diabetes, whether it's type 1 or type 2. It takes work to manage blood sugar levels, but new technologies are making it easier.

By controlling blood sugar levels and managing risk factors to reduce the chances of developing heart disease, stroke, and other diseases, people with diabetes can live a long, quality life.

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  1. Centers for Disease Control and Prevention. The facts, stats, and impacts of diabetes.

  2. Centers for Disease Control and Prevention. What is diabetes?

  3. National Institute of Diabetes and Digestive and Kidney Diseases. Symptoms and causes of diabetes.

  4. Centers for Disease Control and Prevention. Diabetic ketoacidosis.

  5. Centers for Disease Control and Prevention. Diabetes and nerve damage.

  6. Centers for Disease Control and Prevention. Diabetes and your feet.

  7. National Institute of Diabetes and Digestive and Kidney Diseases. What is kidney failure?

  8. Centers for Disease Control and Prevention. Diabetes and your heart.

  9. American Heart Association. Cardiovascular disease and diabetes.

  10. American Diabetes Association. Hypoglycemia (low blood glucose).

  11. Centers for Disease Control and Prevention. Diabetes and mental health.

  12. Centers for Disease Control and Prevention. 10 tips for coping with diabetes distress.

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