Adult-onset diabetes - Type 2 Diabetes Mellitus
Key points
- Diabetes mellitus, commonly called just diabetes, is a common disorder that affects the way the body processes and uses carbohydrates, fats and proteins.
- The symptoms of diabetes are related to high blood-glucose levels.
- Aging and episodic illness can cause the body's insulin resistance to increase, so additional treatment typically is required over time.
- You can help to prevent type 2 diabetes by maintaining your ideal body weight, especially if you have a strong family history of diabetes.
What Is It?
Diabetes mellitus, commonly called just diabetes, is a common disorder that affects the way the body processes and uses carbohydrates, fats and proteins. Each of these nutrients is a source of glucose (sugar), which is the most basic fuel for the body. The most obvious sign of diabetes is a high level of sugar in the blood.
Glucose enters body cells with the help of a hormone called insulin, which acts somewhat like a gatekeeper. Without insulin, which is produced by the pancreas, glucose cannot pass through the cell wall, and the cell "starves." Type 2 diabetes occurs when your body's cells do not react efficiently to insulin produced by the pancreas, a condition called insulin resistance. In people with insulin resistance, the pancreas at first manufactures extra insulin to maintain a normal blood sugar. Eventually, as the body's insulin resistance progresses, the pancreas is unable to keep up with the demand for more and more insulin, and blood-glucose levels rise.
About 95 percent of people with diabetes have type 2 diabetes, also called adult-onset diabetes or non-insulin-dependent diabetes. Type 2 diabetes runs in families, and it commonly affects people who are older than 40. With the rise in obesity that has been seen in the United States in the last decade, type 2 diabetes increasingly is being seen in younger people, particularly African-Americans, Hispanics, and American Indians. Obesity, especially central obesity, greatly increases the risk of diabetes. Central obesity occurs when more fat accumulates around the waist than in the hip area. This is the fat pattern that often is associated with insulin resistance and a condition known as metabolic syndrome.
Metabolic syndrome, originally called syndrome X, is a set of abnormalities that increase the risk of heart disease and stroke. The hallmarks of the metabolic syndrome include obesity, insulin resistance with high-normal or slightly elevated blood sugar, increased blood levels of insulin (hyperinsulinemia), high blood pressure, elevated levels of triglycerides, and low levels of high-density lipoprotein (HDL) cholesterol (the "good" cholesterol). These abnormalities commonly occur together and are related to each other by a genetic or metabolic link. Both the metabolic syndrome and type 2 diabetes increase the risk of heart disease, stroke and peripheral artery disease.
Symptoms
The symptoms of diabetes are related to high blood-glucose levels. They include:
- Excessive urination, thirst and hunger
- Weight loss
- Increased susceptibility to infections, especially yeast or fungal infections of the skin and vagina
Extremely high blood-sugar levels can lead to a dangerous complication called hyperosmolar syndrome, also known as hyperosmolar hyperglycemic nonketotic syndrome (HHNS), hyperosmolar hyperglycemic state (HHS), or hyperosmolar coma. Hyperosmolar syndrome is a life-threatening form of dehydration that can result from untreated high blood-sugar levels. Hyperosmolar syndrome can complicate a severe acute illness, such as a stroke; it can also happen when poor fluid intake triggers dehydration. In some cases, hyperosmolar coma is the first sign that a person has type 2 diabetes.
Written and revised by
David Cohen, M.D.
Our doctors write and review articles for accuracy and keep them up to date.
health.am provides general information, not medical advice. Always consult a qualified health professional about your own health.