Type 1 Diabetes: Characteristics

Diabetes is classified according to the presence of hyperglycemia as a result of abnormalities in insulin production, insulin action, or a combination of both. Type 1 diabetes is one category and is defined as an autoimmune destruction of the beta cells of the pancreas, causing total insulin deficiency. In a nondiabetes state, the pancreas is stimulated to produce insulin by increased blood glucose levels. Therefore, an individual without diabetes can eat a large candy bar with a regular soda and their pancreas will produce enough insulin to compensate for the additional carbohydrate intake, thus, keeping the blood glucose levels in a normal range (target: premeal 80-130 mg/dL; postmeal less than 180 mg/dL). Since the body is unable to produce insulin in type 1 diabetes, the patient relies on exogenous insulin, which is injected as needed throughout the day.

Typically the onset of type 1 diabetes is abrupt and can occur at any age, however, it is most common before the age of 30. Classic symptoms include weight loss, polyuria, polydipsia, polyphagia, and ketoacidosis. A medical emergency occurring more frequently in patients with type 1 diabetes is diabetic ketoacidosis (DKA) in which the glucose values will be above 300 mg/dL. Symptoms include ketosis, acidosis, and dehydration. Screening for type 1 diabetes is not practical due to the low incidence and abrupt onset.6