Updated June 16, 2006

Diabetes

A disease characterized by high blood glucose levels. Type 1 diabetes is an autoimmune disorder in which the immune system attacks and destroys the insulin-producing beta cells in the pancreas. In Type 2 diabetes, there are two main underlying reasons for high blood glucose: insulin resistance, a condition in which the body does not use insulin efficiently, and insufficient insulin secretion by the pancreas. Gestational diabetes is diabetes diagnosed during pregnancy. It may disappear after childbirth, but it is likely to develop again during subsequent pregnancies. Women with gestational diabetes are also at a higher risk of developing Type 2 diabetes later in life.

Symptoms of diabetes include unusual thirst, a need to urinate frequently, unexplained weight loss, blurry vision, and a feeling of being tired constantly. Such symptoms tend to be more acute in Type 1 diabetes. In fact, many people with Type 2 diabetes are unaware that they have it.

Diabetes is diagnosed in one of three ways: a fasting plasma glucose test, an oral glucose tolerance test, or a random plasma glucose test. All involve drawing blood to measure the amount of glucose in it.

Treatment for Type 1 diabetes always includes taking insulin and may include taking other drugs to prevent kidney damage or to treat diabetes-related conditions such as high blood pressure. Treatment for Type 2 diabetes may include taking oral medicines to decrease insulin resistance and/or increase insulin secretion and taking other drugs to treat any diabetes-related conditions; it may also include taking insulin. Attention to diet and regular exercise are important treatment components for both types of diabetes. Weight loss can also help to reverse insulin resistance and lower blood glucose if a person is overweight. Gestational diabetes is most commonly treated either with just diet and exercise or with diet, exercise, and insulin.

The goal in any diabetes treatment is to keep blood glucose and blood pressure levels as close to normal as possible. Chronically high blood glucose levels can damage many parts of the body, including the eyes, kidneys, nerves, and cardiovascular system. In pregnant women, high blood glucose can cause birth defects in the baby and pregnancy complications in the mother. High blood pressure can also do widespread damage to the body. However, studies have shown that "tight" blood glucose and blood pressure control lowers the risk of complications significantly.

Blood glucose level can be monitored at home with a blood glucose meter. The American Diabetes Association (ADA) recommends that most people with diabetes aim for the following treatment goals: When using a meter that gives whole blood glucose levels, the target goal before a meal is between 80 mg/dl and 120 mg/dl. When using a meter that gives plasma glucose levels, the target goal before a meal is between 90 mg/dl and 130 mg/dl. (Whether a meter gives whole blood glucose values or plasma glucose values should be indicated in the literature that comes with the meter.) People who use insulin are generally advised to check their blood glucose level more frequently than those who don’t.

Another blood test that helps to evaluate blood glucose control is the glycosylated hemoglobin (HbA1c) test. This blood test is usually done in a doctor’s office or medical laboratory, although there are some home tests on the market. The ADA recommends that people while diabetes in general aim for an HbA1c reading below 7%, while induviduals and their doctors consider aiming for readings below 6%, which is considered normal. Measuring HbA1c every 3–6 months is recommended.

This article was written by the Editors of Diabetes Self-Management.

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