Type 2 diabetes
| Type 2 diabetes | |
|---|---|
| Other names | Diabetes mellitus type 2; adult-onset diabetes; non-insulin-dependent diabetes mellitus (NIDDM) |
| A blue circle is the universal symbol of diabetes. | |
| Pronunciation |
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| Specialty | Endocrinology |
| Symptoms | Increased thirst, frequent urination, unexplained weight loss, increased hunger |
| Complications | Hyperosmolar hyperglycemic state, diabetic ketoacidosis, heart disease, stroke, diabetic retinopathy, kidney failure, lower-limb amputations |
| Usual onset | Middle or older age |
| Duration | Long term |
| Causes | Obesity, lack of exercise, genetics |
| Diagnostic method | Blood test |
| Prevention | Maintaining normal weight, exercising, healthy diet |
| Treatment | Dietary changes, exercise diabetes medication such as metformin and insulin, bariatric surgery |
| Prognosis | 10 year shorter life expectancy |
| Frequency | 392 million (2015) |
Type 2 diabetes (T2D), formerly known as adult-onset diabetes, is a form of diabetes mellitus that is characterized by high blood sugar, insulin resistance, and relative lack of insulin. Common symptoms include increased thirst, frequent urination, fatigue and unexplained weight loss. Other symptoms include increased hunger, having a sensation of pins and needles, and sores (wounds) that heal slowly. Symptoms often develop slowly. Long-term complications from high blood sugar include heart disease, stroke, diabetic retinopathy, which can result in blindness, kidney failure, and poor blood flow in the lower limbs, which may lead to amputations. A sudden onset of hyperosmolar hyperglycemic state may occur; however, ketoacidosis is uncommon.
Type 2 diabetes primarily occurs as a result of obesity and lack of exercise. Some people are genetically more at risk than others. Type 2 diabetes makes up about 90% of cases of diabetes, with the other 10% due primarily to type 1 diabetes and gestational diabetes.
Diagnosis of diabetes is by blood tests such as fasting plasma glucose, oral glucose tolerance test, or glycated hemoglobin (A1c).
Type 2 diabetes is largely preventable by staying at a normal weight, exercising regularly, and eating a healthy diet (high in fruits and vegetables and low in sugar and saturated fat).
Treatment involves exercise and dietary changes. If blood sugar levels are not adequately lowered, the medication metformin is typically recommended. Many people may eventually also require insulin injections. In those on insulin, routinely checking blood sugar levels (such as through a continuous glucose monitor) is advised; however, this may not be needed in those who are not on insulin therapy. Bariatric surgery often improves diabetes in those who are obese.
Rates of type 2 diabetes have increased markedly since 1960 in parallel with obesity. As of 2015, there were approximately 392 million people diagnosed with the disease compared to around 30 million in 1985. Typically, it begins in middle or older age, although rates of type 2 diabetes are increasing in young people. Type 2 diabetes is associated with a ten-year-shorter life expectancy. Diabetes was one of the first diseases ever described, dating back to an Egyptian manuscript from c. 1500 BCE. Type 1 and type 2 diabetes were identified as separate conditions in 400–500 CE with type 1 associated with youth and type 2 with being overweight. The importance of insulin in the disease was determined in the 1920s.