An estimated 18.2 million people--6.3 percent of the population--in the United States have diabetes--a serious, lifelong condition. Of those, 13 million have been diagnosed. About 5.2 million people have not yet been diagnosed. Each year, about 1.3 million people age 20 or older are diagnosed with diabetes.
What is diabetes?
Diabetes is a disorder of metabolism--the way our bodies use digested food for growth and energy. Most of the food we eat is broken down into glucose, the form of sugar in the blood. Glucose is the main source of fuel for the body.
After digestion, glucose passes into the bloodstream, where it is used by cells for growth and energy. For glucose to get into 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 glucose from blood into our cells. In people with diabetes, however, the pancreas either produces little or no insulin, or the cells do not respond appropriately to the insulin that is produced. 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.
What are the types of diabetes?
The three main types of diabetes are:
- type 1 diabetes
- type 2 diabetes
- gestational diabetes
Type 1 Diabetes
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 the insulin-producing beta cells in the pancreas and destroys them. The pancreas then produces little or no insulin. Someone with type 1 diabetes needs to 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.
Type 1 diabetes develops most often in children and young adults, but the disorder 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 include increased thirst and urination, constant hunger, weight loss, blurred vision, and extreme fatigue. If not diagnosed and treated with insulin, a person can lapse into a life-threatening diabetic coma, also known as diabetic ketoacidosis.
Type 2 Diabetes
The most common form of diabetes is type 2 diabetes. About 90 to 95 percent of people with diabetes have type 2. This form of diabetes is associated with older age, obesity, family history of diabetes, previous history of gestational diabetes, physical inactivity, and ethnicity. About 80 percent of people with type 2 diabetes are overweight. Type 2 diabetes is increasingly being diagnosed in children and adolescents. However, nationally representative data on prevalence of type 2 diabetes in youth are not available.
When type 2 diabetes is diagnosed, the pancreas is usually producing enough insulin, but, for unknown reasons, the body cannot use the insulin effectively, a condition called insulin resistance. After several years, insulin production decreases. The result is the same as for type 1 diabetes--glucose builds up in the blood and the body cannot make efficient use of its main source of fuel.
The symptoms of type 2 diabetes develop gradually. They are not as sudden in onset as in type 1 diabetes. Some people have no symptoms. Symptoms may include fatigue or nausea, frequent urination, unusual thirst, weight loss, blurred vision, frequent infections, and slow healing of wounds or sores.
Gestational Diabetes
Gestational diabetes develops only during pregnancy. Like type 2 diabetes, it occurs more often in African Americans, American Indians, Hispanic Americans, and among women with a family history of diabetes. Women who have had gestational diabetes have a 20 to 50 percent chance of developing type 2 diabetes within 5 to 10 years.
What tests are recommended for diagnosing diabetes?
The fasting plasma glucose test is the preferred test for diagnosing type 1 or type 2 diabetes and is most reliable when done in the morning. However, a diagnosis of diabetes is made for any one of three positive tests, with a second positive test on a different day:
- A random plasma glucose value (taken any time of day) of 200 mg/dL or more, along with the presence of diabetes symptoms.
- A plasma glucose value of 126 mg/dL or more, after a person has fasted for 8 hours.
- An oral glucose tolerance test (OGTT) plasma glucose value of 200 mg/dL or more in the blood sample, taken 2 hours after a person has consumed a drink containing 75 grams of glucose dissolved in water. This test, taken in a laboratory or the doctor's office, measures plasma glucose at timed intervals over a 3-hour period.
Gestational diabetes is diagnosed based on plasma glucose values measured during the OGTT. Glucose levels are normally lower during pregnancy, so the threshold values for diagnosis of diabetes in pregnancy are lower. If a woman has two plasma glucose values meeting or exceeding any of the following numbers, she has gestational diabetes: a fasting plasma glucose level of 95 mg/dL, a 1-hour level of 180 mg/dL, a 2-hour level of 155 mg/dL, or a 3-hour level of 140 mg/dL.
What is pre-diabetes?
People with pre-diabetes, a state between "normal" and "diabetes," are at risk for developing diabetes, heart attacks, and strokes. However, studies suggest that weight loss and increased physical activity can prevent or delay diabetes. There are two forms of pre-diabetes, Impaired Fasting Glucose and Impaired Glucose Tolerance.
What are the scope and impact of diabetes?
Diabetes is widely recognized as one of the leading causes of death and disability in the United States. In 2000, it was the sixth leading cause of death. However, diabetes is likely to be underreported as the underlying cause of death on death certificates. About 65 percent of deaths among those with diabetes are attributed to heart disease and stroke.
Diabetes is associated with long-term complications that affect almost every part of the body. The disease often leads to blindness, heart and blood vessel 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.
Who gets diabetes?
Diabetes is not contagious. However, certain factors can increase the risk of developing diabetes. Ethnicity is a large factor in diabetes. Exercise, diet, and weight are also prime factors in the development of diabetes.
According to recent estimates, the prevalence of diabetes in the United States is predicted to grow to be 8.9 percent of the population by 2025, due to changes in the size of ethnic groups in the US, as well as the trend towards obesity and lack of exercise.
How is diabetes managed?
Today, healthy eating, physical activity, and insulin via injection or an insulin pump are the basic therapies for type 1 diabetes. The amount of insulin must be balanced with food intake and daily activities. Blood glucose levels must be closely monitored through frequent blood glucose checking.
Healthy eating, physical activity, and blood glucose testing are the basic management tools for type 2 diabetes. In addition, many people with type 2 diabetes require oral medication, insulin, or both to control their blood glucose levels.
When blood glucose levels drop too low--a condition known as hypoglycemia--a person can become nervous, shaky, and confused. Judgment can be impaired. If blood glucose falls too low, a person can faint.
A person can also become ill if blood glucose levels rise too high, a condition known as hyperglycemia.
The more closely blood glucose levels are monitored and corrected, the fewer complications will arise as a result of the diabetes.
Hope through research.
Many organizations support diabetes research and education activities. In recent years, advances in diabetes research have led to better ways to manage diabetes and treat its complications. Major advances include:
- the development of quick-acting and long-acting insulin analogues
- better ways to monitor blood glucose and for people with diabetes to check their own blood glucose levels
- research advances in noninvasive blood glucose monitoring
- development of external insulin pumps that deliver insulin, replacing daily injections
- laser treatment for diabetic eye disease, reducing the risk of blindness
- successful transplantation of kidneys and pancreas in people whose own kidneys fail because of diabetes
- better ways of managing diabetes in pregnant women, improving chances of successful outcomes
- new drugs to treat type 2 diabetes and better ways to manage this form of diabetes through weight control
- evidence that intensive management of blood glucose reduces and may prevent development of diabetes complications
- demonstration that two types of antihypertensive drugs, ACE (angiotensin-converting enzyme) inhibitors and ARBs (angiotensin receptor blockers), are more effective in reducing a decline in kidney function than other antihypertensive drugs in people with diabetes
- promising results with islet transplantation for type 1 diabetes reported by the University of Alberta in Canada
- evidence that people at high risk for type 2 diabetes can lower their chances of developing the disease through diet, weight loss, and physical activity
These organizations also continue to research ways to prevent, treat, and manage diabetes, as well as the complications that arise from it.
Credit : National Diabetes Information Clearinghouse (http://www.niddk.nih.gov/ )