Diabetes mellitus, often simply referred to as diabetes—is a group of metabolic diseases in which a
person has high blood sugar, either because the body does not produce enough insulin, or because cells
do not respond to the insulin that is produced. This high blood sugar produces the classical symptoms
of polyuria (frequent urination), polydipsia (increased thirst) and polyphagia (increased hunger).
There are three main types of diabetes:
* Type 1 diabetes: results from the body's failure to produce insulin, and presently requires
the person to inject insulin. (Also referred to as insulin-dependent diabetes mellitus, IDDM
for short, and juvenile diabetes.)
* Type 2 diabetes: results from insulin resistance, a condition in which cells fail to use insulin
properly, sometimes combined with an absolute insulin deficiency. (Formerly referred to as
non-insulin-dependent diabetes mellitus, NIDDM for short, and adult-onset diabetes.)
* Gestational diabetes: is when pregnant women, who have never had diabetes before, have a high
blood glucose level during pregnancy. It may precede development of type 2 DM.
Other forms of diabetes mellitus include congenital diabetes, which is due to genetic defects of
insulin secretion, cystic fibrosis-related diabetes, steroid diabetes induced by high doses of
glucocorticoids, and several forms of monogenic diabetes.
All forms of diabetes have been treatable since insulin became available in 1921, and type 2 diabetes
may be controlled with medications. Both type 1 and 2 are chronic conditions that usually cannot be
cured. Pancreas transplants have been tried with limited success in type 1 DM; gastric bypass surgery
has been successful in many with morbid obesity and type 2 DM. Gestational diabetes usually resolves
after delivery. Diabetes without proper treatments can cause many complications. Acute complications
include hypoglycemia, diabetic ketoacidosis, or nonketotic hyperosmolar coma.
complications include cardiovascular disease, chronic renal failure, retinal damage. Adequate treatment
of diabetes is thus important, as well as blood pressure control and lifestyle factors such as smoking
cessation and maintaining a healthy body weight.