Although diabetes occurs most often in older adults, it is one of the most common chronic disorders in children in the United States. About 127,000 children and teenagers age 19 and younger have diabetes.
After digestion, the glucose passes into our bloodstream where it is available for body cells to use for growth and energy. For the glucose to get into the cells, insulin must be present. Insulin is a hormone produced by the pancreas, a large gland behind the stomach.
When we eat, the pancreas is supposed to automatically produce the right amount of insulin to move the glucose from our blood into our cells. In people with diabetes, however, the pancreas either produces little or no insulin, or the body cells do not respond to the insulin that is produced. As a result, glucose builds up in the blood, overflows into the urine, and passes out of the body. Thus, the body loses its main source of fuel even though the blood contains large amounts of glucose.
Someone with IDDM needs daily injections of insulin 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 both genetic factors and viruses are involved. IDDM accounts for about 5 to 10 percent of diagnosed diabetes in the United States.
IDDM develops most often in children and young adults, but the disorder can appear at any age. Symptoms of IDDM usually develop over a short period, although beta cell destruction can begin months, even years, earlier.
Symptoms include increased thirst and urination, constant hunger, weight loss, blurred vision, and extreme tiredness. If not diagnosed and treated with insulin, a person can lapse into a life-threatening coma.
In NIDDM, the pancreas usually produces insulin, but for some reason, the body cannot use the insulin effectively. The end result is the same as for IDDM-an unhealthy buildup of glucose in the blood and an inability of the body to make efficient use of its main source of fuel.
The symptoms of NIDDM develop gradually and are not as noticeable as in IDDM. Symptoms include feeling tired or ill, frequent urination (especially at night), unusual thirst, weight loss, blurred vision, frequent infections, and slow healing of sores.
Diabetes is associated with long-term complications that affect almost every major part of the body. It contributes to blindness, heart disease, strokes, kidney failure, amputations, and nerve damage. Uncontrolled diabetes can complicate pregnancy, and birth defects are more common in babies born to women with diabetes.
Diabetes cost the United States $92 billion in 1992. Indirect costs, including disability payments, time lost from work, and premature death, totaled $47 billion; medical costs for diabetes care, including hospitalizations, medical care, and treatment supplies, totaled $45 billion.
IDDM occurs equally among males and females, but is more common in whites than in nonwhites. Data from the World Health Organization's Multinational Project for Childhood Diabetes indicate that IDDM is rare in most Asian, African, and Native American populations. On the other hand, some northern European countries, including Finland and Sweden, have high rates of IDDM. The reasons for these differences are not known.
NIDDM is more common in older people, especially older women who are overweight, and occurs more often among African Americans, Hispanics, and Native Americans. Compared with non-Hispanic whites, diabetes rates are about 60 percent higher in African Americans and 110 to 120 percent higher in Mexican Americans and Puerto Ricans. Native Americans have the highest rates of diabetes in the world. Among Pima Indians living in the United States, for example, half of all adults have NIDDM. The prevalence of diabetes is likely to increase because older people, Hispanics, and other minority groups make up the fastest growing segments of the U.S. population.
Today, daily injections of insulin are the basic therapy for IDDM. Insulin injections must be balanced with meals and daily activities, and glucose levels must be closely monitored through frequent blood sugar testing.
Diet, exercise, and blood testing for glucose are also the basis for management of NIDDM. In addition, some people with NIDDM take oral drugs or insulin to lower their blood glucose levels.
People with diabetes must take responsibility for their day-to-day care. Much of the daily care involves trying to keep blood sugar levels from going too low or too high. When blood sugar levels drop too low--a condition known as hypoglycemia--a person can become nervous, shaky, and confused. Judgment can be impaired. Eventually, the person could pass out. The treatment for low blood sugar is to eat or drink something with sugar in it.
On the other hand, a person can become very ill if blood sugar levels rise too high, a condition known as hyperglycemia. Hypoglycemia and hyperglycemia, which can occur in people with IDDM or NIDDM, are both potentially life-threatening emergencies.
People with diabetes should be treated by a doctor who monitors their diabetes control and checks for complications. Doctors who specialize in diabetes are called endocrinologists or diabetologists. In addition, people with diabetes often see ophthalmologists for eye examinations, podiatrists for routine foot care, dietitians for help in planning meals, and diabetes educators for instruction in day-to-day care.
The goal of diabetes management is to keep blood glucose levels as close to the normal (nondiabetic) range as safely possible. A recent Government study, sponsored by the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), proved that keeping blood sugar levels as close to normal as safely possible reduces the risk of developing major complications of diabetes.
The 10-year study, called the Diabetes Control and Complications Trial (DCCT), was completed in 1993 and included 1,441 people with IDDM. The study compared the effect of two treatment approaches--intensive management and standard management--on the development and progression of eye, kidney, and nerve complications of diabetes. Researchers found that study participants who maintained lower levels of blood glucose through intensive management had significantly lower rates of these complications.
Researchers believe that DCCT findings have important implications for the treatment of NIDDM, as well as IDDM.
Other Government agencies that sponsor diabetes programs are the Centers for Disease Control and Prevention, the Indian Health Service, the Health Resources and Services Administration, the Bureau of Veterans Affairs, and the Department of Defense.
Many organizations outside of the Government support diabetes research and education activities. These organizations include the American Diabetes Association, the Juvenile Diabetes Foundation International, and the American Association of Diabetes Educators.
In recent years, advances in diabetes research have led to better ways to manage diabetes and treat its complications. Major advances include:
Researchers continue to search for the cause or causes of diabetes and ways to prevent and cure the disorder. Scientists are looking for genes that may be involved in NIDDM and IDDM. Some genetic markers for IDDM have been identified, and it is now possible to screen relatives of people with IDDM to see if they are at risk for diabetes.
The new Diabetes Prevention Trial-Type I, sponsored by NIDDK, identifies relatives at risk for developing IDDM and treats them with low doses of insulin or with oral insulin-like agents in the hope of preventing IDDM. Similar research is carried out at other medical centers throughout the world.
Transplantation of the pancreas or insulin-producing beta cells offers the best hope of cure for people with IDDM. Some pancreas transplants have been successful. However, people who have transplants must take powerful drugs to prevent rejection of the transplanted organ. These drugs are costly and may eventually cause serious health problems.
Scientists are working to develop less harmful drugs and better methods of transplanting pancreatic tissue to prevent rejection by the body. Using techniques of bioengineering, researchers are also trying to create artificial islet cells that secrete insulin in response to increased sugar levels in the blood.
For NIDDM, the focus is on ways to prevent diabetes. Preventive approaches include identifying people at high risk for the disorder and encouraging them to lose weight, exercise more, and follow a healthy diet. The Diabetes Prevention Program, another new NIDDK project, will focus on preventing the disorder in high-risk populations.
Points to RememberWhat Is Diabetes
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