Type 1 Diabetes

Overview

Type 1 diabetes is an autoimmune disease. An autoimmune disease results when the body’s system for fighting infection—the immune system—turns against a part of the body. In diabetes, the immune system attacks and destroys the insulin-producing beta cells in the pancreas.

The pancreas then produces little or no insulin. A person who has type 1 diabetes must take insulin daily to live.

At present, scientists do not know exactly what causes the body’s immune system to attack the beta cells, but they believe that autoimmune, genetic, and environmental factors, possibly viruses, are involved. Type 1 diabetes accounts for about 5 to 10 percent of diagnosed diabetes in the United States. It develops most often in children and young adults but can appear at any age.

Symptoms of type 1 diabetes usually develop over a short period, although beta cell destruction can begin years earlier. Symptoms may include increased thirst and urination, constant hunger, weight loss, blurred vision, and extreme fatigue. If not diagnosed and treated with insulin, a person with type 1 diabetes can lapse into a life-threatening diabetic coma, also known as diabetic ketoacidosis.

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Symptoms

These symptoms may be the first signs of type 1 diabetes, or may occur when the blood sugar is high:

  • Being very thirsty
  • Feeling hungry
  • Feeling tired or fatigued
  • Having blurry eyesight
  • Losing the feeling or feeling tingling in your feet
  • Losing weight without trying
  • Urinating more often

For other people, these warning symptoms may be the first signs of type 1 diabetes, or they may happen when the blood sugar is very high:

  • Deep, rapid breathing
  • Dry skin and mouth
  • Flushed face
  • Fruity breath odor
  • Nausea or vomiting, inability to keep down fluids
  • Stomach pain

Low blood sugar (hypoglycemia) can develop quickly in people with diabetes who are taking insulin. Symptoms usually appear when the blood sugar level falls below 70 mg/dL. Watch for:

  • Headache
  • Hunger
  • Nervousness
  • Rapid heartbeat (palpitations)
  • Shaking
  • Sweating
  • Weakness

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Diagnosis

The fasting blood glucose test is the preferred test for diagnosing diabetes in children and nonpregnant adults. The test is most reliable when done in the morning. However, a diagnosis of diabetes can be made based on any of the following test results, confirmed by retesting on a different day:

  • A blood glucose level of 126 milli grams per deciliter (mg/dL) or higher after an 8-hour fast. This test is called the fasting blood glucose test.
  • A blood glucose level of 200 mg/dL or higher 2 hours after drinking a beverage containing 75 grams of glucose dissolved in water. This test is called the oral glucose tolerance test (OGTT).
  • A random—taken at any time of day—blood glucose level of 200 mg/dL or higher, along with the presence of diabetes symptoms.

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Treatments

Because type 1 diabetes can start quickly and the symptoms can be severe, people who have just been diagnosed may need to stay in the hospital.

If you have just been diagnosed with type 1 diabetes, you should probably have a check-up each week until you have good control over your blood sugar. Your health care provider will review the results of your home blood sugar monitoring and urine testing. Your provider will also look at your diary of meals, snacks, and insulin injections.

As the disease gets more stable, you will have fewer follow-up visits. Visiting your health care provider is very important so you can monitor any long-term problems from diabetes.

You are the most important person in managing your diabetes. You should know the basic steps to diabetes management:

  • How to recognize and treat low blood sugar (hypoglycemia)
  • How to recognize and treat high blood sugar (hyperglycemia)
  • Diabetes meal planning
  • How to give insulin
  • How to check blood glucose and urine ketones
  • How to adjust insulin and food when you exercise
  • How to handle sick days
  • Where to buy diabetes supplies and how to store them

Insulin

Insulin lowers blood sugar by allowing it to leave the bloodstream and enter cells. Everyone with type 1 diabetes must take insulin every day.

Insulin is usually injected under the skin. In some cases, a pump delivers the insulin all the time. Insulin does not come in pill form.

Insulin types differ in how fast they start to work and how long they last. The health care provider will choose the best type of insulin for you and will tell you at what time of day to use it. More than one type of insulin may be mixed together in an injection to get the best blood glucose control. You may need insulin shots from one to four times a day.

Your health care provider or diabetes nurse educator will teach you how to give insulin injections. At first, a child's injections may be given by a parent or other adult. By age 14, most children can give their own injections.

People with diabetes need to know how to adjust the amount of insulin they are taking:

  • When they exercise
  • When they are sick
  • When they will be eating more or less food and calories
  • When they are traveling

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Causes

Type 1 diabetes can occur at any age. However, it is most often diagnosed in children, adolescents, or young adults.

Insulin is a hormone produced by special cells, called beta cells, in the pancreas. The pancreas is found behind your stomach. Insulin is needed to move blood sugar (glucose) into cells, where it is stored and later used for energy. In type 1 diabetes, beta cells produce little or no insulin.

Without enough insulin, glucose builds up in the bloodstream instead of going into the cells. The body is unable to use this glucose for energy. This leads to the symptoms of type 1 diabetes.

The exact cause of type 1 diabetes is unknown. Most likely it is an autoimmune disorder. An infection or some other trigger causes the body to mistakenly attack the cells in the pancreas that make insulin. This kind of disorder can be passed down through families.

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Getting Help

Call 911 if you have:

  • Chest pain or pressure, shortness of breath, or other signs of angina
  • Loss of consciousness
  • Seizures

Call your health care provider or go to the emergency room if you have symptoms of diabetic ketoacidosis.

Also call your doctor if you have:

  • Blood sugar levels that are higher than the goals you and your doctor have set
  • Numbness, tingling, or pain in your feet or legs
  • Problems with your eyesight
  • Sores or infections on your feet
  • Symptoms that your blood sugar is getting too low (feeling weak or tired, trembling, sweating, feeling irritable, having trouble thinking clearly, fast heartbeat, double or blurry vision, feeling uneasy)
  • Symptoms that your blood sugar is too high (being very thirsty, having blurry vision, having dry skin, feeling weak or tired, needing to urinate a lot)
  • You are having blood sugar readings below 70 mg/dL

You can treat early signs of hypoglycemia at home by eating sugar or candy, or by taking glucose tablets. If your signs of hypoglycemia continue or your blood glucose levels stay below 60 mg/dL, go to the emergency room.

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Related Information

If you have diabetes, your risk of a heart attack is the same as someone who has already had a heart attack. Both women and men with diabetes are at risk. You may not even have the normal signs of a heart attack.

After many years, diabetes can lead to other serious problems:

  • You could have eye problems, including trouble seeing (especially at night) and sensitivity to light. You could become blind.
  • Your feet and skin could develop sores and infections. If you have these sores for too long, your foot or leg may need to be removed. Infection can also cause pain and itching.
  • Diabetes may make it harder to control your blood pressure and cholesterol. This can lead to heart attack, stroke, and other problems. It can become harder for blood to flow to the legs and feet.
  • Nerves in the body can become damaged, causing pain, tingling, and loss of feeling.
  • Because of nerve damage, you could have problems digesting the food you eat. You could feel weakness or have trouble going to the bathroom. Nerve damage can also make it harder for men to have an erection.
  • High blood sugar and other problems can lead to kidney damage. The kidneys might not work as wellas they used to. They may even stop working.

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Living With

Diabetes is a lifelong disease and there is not yet a cure. However, the outcome for people with diabetes varies.

Studies show that tight control of blood glucose can prevent or delay problems with the eyes, kidneys, nervous system, and heart in type 1 diabetes. However, problems may occur even in people with good diabetes control.

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Reviewed by: 
Joseph V. Madia, MD
Review Date: 
May 15, 2012

Last Updated:
October 4, 2012