What is type 2 diabetes?
Type 2 diabetes is characterized by "insulin resistance" as body cells do not respond appropriately when insulin is present. This is a more complex problem than type 1, but is sometimes easier to treat, since insulin is still produced in many, especially in the intial years. Type 2 may go unnoticed for years in a patient before diagnosis, since the symptoms are
typically milder (no ketoacidosis) and can be sporadic. However, severe complications can result from unnoticed Type 2 diabetes, including hypertension, renal failure, and coronary artery disease.
Type 2 diabetes was formerly known by a variety of partially misleading names, inlcuding "adult-onset diabetes", "obesity-related diabetes", "insulin-resistant diabetes", or "non-insulin-dependent diabetes" (NIDDM). It may be caused by a number of diseases, such as hemochromatosis and polycystic ovary syndrome, and can also be caused by certain types of medications (e.g., long-term steroid use). About 90-95% of all North American cases of diabetes are Type 2, and about 20% of the population over the age of 65 is a Type 2 diabetic. The fraction of Type 2 diabetics in other parts of the world varies substantially, almost certainly for environmental reasons. There is also a very strong inheritable genetic connection in type 2 diabetes - having relatives, especially close ones, with type 2 is a considerable risk factor for developing type 2 diabetes. Most patients with type 2 diabetes mellitus are obese - chronic obesity leads to increased insulin resistance that can develop into diabetes, most likely because fat tissue is a (recently identified) source of chemical signals (ie, hormones).
Type 2 is initially treated by changes in diet and through weight loss. This can restore insulin sensitivity, even when the weight lost is modest (e.g. 10-15 lbs or 5 kg). The next step, if necessary, is treatment with oral antidiabetic drugs: the sulphonylureas, metformin, or (if these are insufficient) thiazolidinediones). When these have failed, insulin therapy may be necessary.
Type 2 diabetes mellitus was also referred to as non-insulin dependent diabetes mellitus (NIDDM), or adult onset diabetes mellitus (AODM). In type 2 diabetes, patients can still produce insulin, but do so relatively inadequately. In many cases this actually means the pancreas produces larger than normal quantities of insulin. A major feature of type 2 diabetes is a lack of sensitivity to insulin by the cells of the body (particularly fat and muscle cells) these larger quantities of insulin are produced as an attempt to get these cells to recognize that insulin is present. In addition to the problems with an increase in insulin resistance, the release of insulin by the pancreas may also be defective, and occur late in response to increased glucose levels. Finally, the liver in these patients continues to produce glucose despite elevated glucose levels.
While it is said that type 2 diabetes mellitus occurs mostly in individuals over 30 years old and the incidence increases with age, we are seeing an alarming number patients with type 2 diabetes who are barely in their teen years. Most of these cases are a direct result of poor eating habits, higher body weight, and lack of exercise. While there is a strong genetic component to developing this form of diabetes, there are other risk factors - the most significant of which is obesity. There is a direct relationship between the degree of obesity and the risk of developing type 2 diabetes, and this holds true in children as well as adults. It is estimated that the chance to develop diabetes doubles for every 20% increase over desirable body weight and for each decade after 40 years of age regardless of weight. The prevalence of diabetes in persons 65 to 74 years of age is nearly 20%. Type 2 diabetes is more common in certain ethnic groups. Compared with a 6% prevalence in Caucasians, the prevalence in African Americans and Asian Americans is estimated to be 10%, in Hispanics 15%, and in certain Native American tribes 20% to 50%. Finally, diabetes occurs much more frequently in women with a prior history of diabetes that develops during pregnancy (gestational diabetes). Type 2 diabetes is often associated with a strong familial, probably genetic predisposition. This is less common in the autoimmune form of type 1 diabetes.
You may at first be advised to make changes in your lifestyle - lose some weight and increase your level of physical activity, for example. Weight loss and exercise can be very successful in getting blood glucose levels back down to the normal range. Although it can be very difficult to change habits of a lifetime, the threat of your health deteriorating further may signify that now is the time to stop and take stock of things.
In some people, the 'diet and exercise' approach is simply not enough to bring blood glucose levels into line and extra help is needed. Usually the next step is tablets - known as oral hypoglycaemics - that either help you to produce more insulin, or help your body to use the insulin more effectively. These tablets, however, are only effective if your body is able to produce some insulin. You may be prescribed more than one type of tablet. You should remember that diet, weight loss and exercise are still crucial to the diabetes management plan even when tablets are prescribed.
Some people with Type 2 diabetes need insulin injections. This might be temporary - if your body is under a lot of stress, you have an infection or you have been admitted to hospital for surgery, for example. However, in many cases, Type 2 diabetes is a progressive condition in which insulin production declines slowly over the years. Eventually, not enough insulin is produced and then there is no alternative but to start on injections. If this happens to you then you must remember that this is not a failing on your part - it is just the natural progression of things.
Regardless of the treatment approach, people with Type 2 diabetes should ideally test blood glucose levels on a day-to-day basis. It is only with this information that you can assess the effects of your daily activities on your blood glucose level.
More information on diabetes mellitus
What is diabetes mellitus? - Diabetes mellitus is a a condition characterized by hyperglycemia resulting from the body's inability to use blood glucose for energy. Diabetes mellitus can result in coma. Over time, complications can include nerve injury, blindness, kidney failure, and premature atherosclerosis with all of its complications.
What causes diabetes mellitus? - Diabetes mellitus is a disorder caused by insufficient production of the hormone insulin by the pancreas, or insensitivity of cells to the effects of insulin. Insulin is responsible for the absorption of glucose into cells for their energy needs and into the liver and fat cells for storage.
What is insulin? - Insulin is a hormone that is produced by specialized cells (beta cells) of the pancreas. In addition to helping glucose enter the cells, insulin is also important in tightly regulating the level of glucose in the blood.
What types of diabetes mellitus are there? - There are four main types of diabetes mellitus. They are type 1 diabetes mellitus, type 2 diabetes mellitus, type 3, and Gestational diabetes mellitus (type 4).
What is type 1 diabetes? - Formerly known as juvenile diabetes or insulin-dependent diabetes, type 1 diabetes is a life-long condition in which the pancreas stops making insulin. Type 1 diabetes develops most often in young people but can appear in adults.
What is type 2 diabetes? - Type 2 diabetes is the most common form of diabetes mellitus. People with type 2 diabetes produce insulin, but either do not make enough insulin or their bodies do not use the insulin they make. Type 2, also known as non-insulin dependent diabetes, typically occurs after the age of 40 years.
What're signs and symptoms of diabetes mellitus? - Type 2 diabetes almost always has a slow onset (often years). Early symptoms of Type 1 diabetes are often polyuria (frequent urination) and polydipsia (increased thirst, and consequent increased fluid intake).
What is diabetes insipidus? - Diabetes insipidus (DI) is a disease characterized by excretion of large amounts of severely diluted urine, which cannot be reduced when fluid intake is reduced.
What is diabetic coma? - Diabetic coma is a medical emergency in which a person with diabetes is unconscious because the blood glucose level is too low or too high. Patients with diabetes mellitus type 1 are especially prone to this condition.
What are the complications of diabetes mellitus? - Many people with diabetes mellitus eventually develop complications. A very common short-term complication of diabetes mellitus is hypoglycemia (abnormally low blood sugar levels).
How to diagnose diabetes mellitus? - The diagnosis of type 1 diabetes is usually prompted by recent symptoms of excessive urination (polyuria) and excessive thirst (polydipsia), often accompanied by weight loss. The diagnosis of other types of diabetes is made in many other ways.
Diagnosis protocol for diabetes - People over age 45 should be tested for diabetes. If the first blood glucose test is normal, they should be re-tested every three years. A diagnosis of diabetes is made when any three of these tests is positive, followed by a second positive test on a different day.
What is the treatment for diabetes? - Diabetes is a chronic disease with no cure, but it can almost always be managed effectively. Nowadays, the goal for diabetics is to avoid or minimize chronic diabetic complications, as well as to avoid acute problems of hyperglycemia or hypoglycemia.
What type of diabetes diet is suggested? - For some people with diabetes mellitus, a healthy diet and weight loss is enough to keep glucose levels in the blood normal.
What medications are available for diabetes? - Oral diabetes medicines, or oral hypoglycemics, can lower blood glucose in people who have diabetes, but are able to make some insulin. Six FDA-approved oral diabetes medications are now on the market.
How to prevent diabetes? - Diabetes prevention is proven, possible, and powerful. Studies show that people at high risk for type 2 diabetes can prevent or delay the onset of the disease by losing 5 to 7 percent of their body weight.
What should a child diabetes do every day? - To control diabetes and prevent complications, blood glucose levels must be as close to a "normal" range as safely possible. Families should work with a health care provider to help set a child's or teen's targets for blood glucose levels.
Smoking and diabetes - There is a growing body of evidence to suggest that smoking is an independent risk factor for diabetes and that among people with diabetes, smoking aggravates the risk of serious disease and premature death.