Type 1 Diabetes [ Insulin Dependent Diabetes Mellitus]

Diabetes mellitus, commonly just called diabetes, is a disease in which the body cannot process or use the energy-giving nutrients in foods. During digestion, food is broken down into basic components, such as fats, amino acids from proteins, and simple sugars from carbohydrates. All of these nutrients can be processed by the liver into one type of simple sugar, glucose, which then enters the bloodstream.

Glucose is the body's main source of energy. It normally enters body cells with the help of a hormone called insulin, which is made by the pancreas. Without insulin, glucose cannot pass through the cell wall and into the cell, which causes the cell to "starve." In diabetes, not enough insulin is available to move glucose into the cells, either because too little insulin is being made or because the cells cannot respond to insulin. Because glucose cannot enter cells, it stays in the blood, which is why people with diabetes have high blood sugar. With too much glucose in the blood and not enough in the cells, the body has to work harder to keep functioning, and organs and bodily systems can suffer severe damage.

Diabetes affects more than just blood sugar. If cells cannot use glucose for energy, they have to use something else. In an effort to provide alternative fuels for the body, the liver produces acidic substances called ketones, which build up in the blood. When ketones are made in large quantities, the blood becomes abnormally acidic. This creates a severe, potentially life-threatening condition called ketoacidosis, which can cause heart problems and affect the nervous system to the point of coma or death.

Disease Origin & Causes

There are three types of diabetes: type 1 diabetes, type 2 diabetes and gestational diabetes. In type 1 diabetes (also called insulin-dependent diabetes or juvenile diabetes) some or all of the insulin-producing cells of the pancreas are destroyed, leaving the patient with little or no naturally produced insulin. Only about 5% to 10% of people in the United States diagnosed with diabetes have type 1. However, type 1 diabetes is the most common type of diabetes in children. In fact, type 1 diabetes is one of the most common chronic diseases in children, according to the American Diabetes Association. It is estimated that one in every 600 children in the US develops type 1 diabetes.

Type 1 diabetes is a chronic (long-lasting) disease that typically begins before age 35. Although it is not unusual for children ages 1 to 4 years to develop the disease, it is diagnosed most commonly between ages 10 and 16. Peak incidence typically occurs around 10 to 12 years of age in girls, and around 12 to 14 years of age in boys.

Type 1 diabetes is an autoimmune disease, which means the body's own immune system attacks the body. In this case, the immune system destroys insulin-producing cells (beta cells) in the pancreas. Over time, the amount of insulin made by the beta cells decreases to the point where there is no longer enough to transport ingested nutrients into the cells. As a result, blood sugar becomes dangerously high. What causes the immune system to attack the beta cells remains a mystery. Current thought is that a genetic (inherited) factor makes a person predisposed to the disease. Later on in life, an environmental factor triggers the actual start of the disease. Viral infections and cow’s milk in the diet are two possible triggers which are currently being examined by researchers.
Type 1 diabetes tends to run in families. Brothers and sisters of children with type 1 diabetes have about a 10 percent chance of developing the disease by age 50. The identical twin of a person with type 1 diabetes has a 25 to 50 percent chance of developing type 1 diabetes. Genetics certainly does not always explain the cause of type 1, as 90 percent of children who develop the disease have no relative with diabetes. We do know for certain that type 1 diabetes has nothing to do with the amount of sugar in a person's diet before the disease develops.

Symptoms

Type 1 diabetes often appears suddenly. In children, type 1 diabetes symptoms may resemble flu symptoms. The following are the most common symptoms for type 1 diabetes. However, each child may experience symptoms differently. Other symptoms may include:

  • unusual thirst
  • frequent urination or bed-wetting
  • extreme hunger but loss of weight
  • blurred vision
  • nausea and vomiting
  • abdominal pain
  • extreme weakness and tiredness
  • irritability and mood changes

Diagnosis

Diabetes is diagnosed by testing the blood for sugar levels. With the fasting plasma glucose (FPG) test, blood is taken in the morning after not eating anything overnight. Typically, the body keeps blood sugar levels between 70 and 100 milligrams per deciliter (mg/dL), even after fasting. Diabetes is diagnosed if a blood sugar level after fasting is greater than 126 mg/dL. Another test, the oral glucose tolerance test (OGTT), involves measuring the blood sugar 2 hours after drinking 75 grams of glucose. Diabetes is diagnosed if the 2-hour blood sugar level is 200 mg/dL or higher.

Treatment

Treatment of type 1 diabetes requires insulin to be injected under the skin to make up for the insulin that is not produced by the body. Most often, this is accomplished with multiple injections per day. The traditional method is to use a syringe. Some patients now use semiautomatic injector pens that help to measure precise amounts of insulin. An increasing number of patients use insulin pumps, worn at the waist or elsewhere on the body, which mimic the pancreas by delivering a regulated dose of insulin from a pack through a needle implanted under the skin. Other ways to deliver insulin, such as inhalation, are being investigated.

In order to properly regulate insulin intake, people with type 1 diabetes need to monitor their blood sugar levels several times per day by testing a sample of blood. This is done by pricking the finger, usually with a spring-loaded device that makes the process less painful. A small drop of blood is placed on a test strip, which then is inserted into a device called a glucose monitor. A highly accurate reading of blood sugar levels is returned within seconds. Newer glucose monitors have test strips that take the blood directly from the spot that was pricked, a process that can require less blood. Some newer monitors also allow blood to be taken from the forearm, thigh or the fleshy part of the hand, which can be less painful.

People with diabetes also need to watch their diets and get regular exercise. A healthy diet for someone with type 1 diabetes is one that keeps the amount of glucose in the blood relatively constant, which makes it easier to control with insulin. A person with type 1 diabetes typically is advised to eat, exercise, and take insulin at about the same times every day. Regular habits help to keep glucose levels within the normal range. A common method of tight blood sugar control involves testing blood sugar several times during the day and taking a fast-acting insulin as needed, depending on the amount of carbohydrates being taken in (carbohydrate counting). Your doctor or dietitian will help you determine the best insulin and diet schedule for your child.

Complications

Although type 1 diabetes can cause many different problems, there are several key complications, including hyperglycemia and ketoacidosis. Hyperglycemia (high blood sugar) is the hallmark of untreated diabetes, but even children receiving treatment can still have periods of hyperglycemia. A child's blood sugar can rise for many reasons, including eating too much, not taking enough insulin, or having an illness. Some signs that hyperglycemia is present include frequent urination, increased thirst, dry mouth, blurred vision, fatigue, and nausea. If hyperglycemia is suspected, it is important to check and record your child's blood sugar. Hyperglycemia may signal a need to adjust your child's meal plan or insulin regimen. If your child's blood sugar is unusually or dangerously high, it is important to call your the doctor right away or seek emergency care. If hyperglycemia persists for too long, ketoacidosis may occur. When the body’s cells are starved for energy, as they are during prolonged hyperglycemia, it may begin to break down fat for energy. This breakdown produces toxic acids known as ketones, and the condition called ketoacidosis. Loss of appetite, nausea, vomiting, fever, stomach pain and a sweet, fruity smell on your child's breath. If you suspect ketoacidosis, check your child's urine for excess ketones with an over-the-counter ketones test kit. If your child has excess ketones in his or her urine, call your child's doctor right away or seek emergency care.

Another complication seen in type 1 diabetes occurs during treatment. Hypoglycemia (low blood sugar, sometimes called an insulin reaction) occurs when blood sugar drops too low. This can happen when there is too much insulin in the body, which can happen after skipping a meal, getting more physical activity than normal or injecting too much insulin. It is important to watch for early signs and symptoms of low blood sugar, including sweating, shakiness, drowsiness, hunger, dizziness and nausea, and treat them promptly. Hypoglycemia can lead to coma if it is not corrected by eating or drinking carbohydrates, or by an injection of glucagon, a substance that makes the liver release glucose into the bloodstream.

Honeymooning

Just after diagnosis, some patients with type 1 diabetes will experience a “honeymoon” phase. Most kids with new onset type 1 diabetes have experienced symptoms and signs due to the absolute lack of insulin, such as increased drinking, increased urination, and weight loss. Due to the loss of the energy efficient glucose/insulin pathway, fat is metabolized for energy using a less efficient pathway with production of ketones. To exhibit symptoms of diabetes, approximately 80 percent of the pancreatic islets are either destroyed or non-functional. Therefore, 20 percent still may be remaining. After initiation of insulin, the efficient energy pathway is resumed and glucose may be transported into the cells and metabolized for energy. The body "breaths a sigh of relief." After the body starts using glucose and the high amounts of glucose bathing the islet cells in the pancreas decrease, the remaining islets may begin to recover the ability to produce insulin. This recovered insulin production results in the honeymoon period. It is important to note that this process does NOT occur in all patients, and it sometimes takes several weeks to a month to start noticing the production of the body's own insulin and decreased injected insulin doses. The length of a honeymoon period is variable; it can last weeks, months, and rarely—years. As a general observation, the younger the patient is at diagnosis, the shorter the “honeymoon” seems to be.

The A1C Test

The best way to remain healthy and prevent the negative long-term effects of diabetes on the body is to maintain adequate blood sugar control. One test that physicians use to determine blood sugar control is called the A1C test. This test measures the amount of sugar attached to hemoglobin in red blood cells. Since red blood cells survive in the bloodstream about 120 days, the A1C test shows the average blood sugar levels for the past two to three months. The recommended goal for people with diabetes is to maintain an A1C of less than 7%

Useful Links:

The American Diabetes Association – Type 1 Diabetes
(http://www.diabetes.org/type-1-diabetes.jsp)

Children With Diabetes
(http://www.childrenwithdiabetes.com/)

The Juvenile Diabetes Research Foundation – Frequently Asked Questions
(http://www.jdrf.org/index.cfm?page_id=103442)

Type 1 Diabetes TrialNet
(http://www.diabetestrialnet.org/index.htm)

Carbohydrate Counting Overview
(http://www.diabetes.org/uedocuments/10-CarbCounting.pdf)

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