Type 1 Diabetes (T1D): 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 (T1D) 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 soft drink 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 T1D 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. Widespread screening for T1D is not practical due to the low incidence and abrupt onset.6