Type 1 diabetes (T1D), formerly known as juvenile diabetes, is an autoimmune disease that originates when cells that make insulin (beta cells) are destroyed by the immune system. Insulin is a hormone required for the cells to use blood sugar for energy and it helps regulate glucose levels in the bloodstream. Before treatment this results in high blood sugar levels in the body. The common symptoms of this elevated blood sugar are frequent urination, increased thirst, increased hunger, weight loss, and other serious complications. Additional symptoms may include blurry vision, tiredness, and slow wound healing. Symptoms typically develop over a short period of time, often a matter of weeks.The cause of type 1 diabetes is unknown, but it is believed to involve a combination of genetic and environmental factors. The underlying mechanism involves an autoimmune destruction of the insulin-producing beta cells in the pancreas. Diabetes is diagnosed by testing the level of sugar or glycated hemoglobin (HbA1C) in the blood. Type 1 diabetes can be distinguished from type 2 by testing for the presence of autoantibodies.There is no known way to prevent type 1 diabetes. Treatment with insulin is required for survival. Insulin therapy is usually given by injection just under the skin but can also be delivered by an insulin pump. A diabetic diet and exercise are important parts of management. If left untreated, diabetes can cause many complications. Complications of relatively rapid onset include diabetic ketoacidosis and nonketotic hyperosmolar coma.
In addition, constant low levels of insulin are achieved with one or two daily doses of long-acting insulin, or by steady infusion of low insulin levels by an insulin pump. The exact dose of insulin appropriate for each injection depends on the content of the meal/snack, and the individual persons sensitivity to insulin, and is therefore typically calculated by the individual with diabetes or a family member by hand or assistive device (calculator, chart, mobile app, etc.). People unable to manage these intensive insulin regimens are sometimes prescribed alternate plans relying on mixtures of rapid- or short-acting and intermediate-acting insulin, which are administered at fixed times along with meals of pre-planned times and carbohydrate composition.The only non-insulin medication approved by the U.S. Food and Drug Administration for treating type 1 diabetes is the amylin analog pramlintide, which replaces the beta-cell hormone amylin. Addition of pramlintide to mealtime insulin injections reduces the boost in blood sugar after a meal, improving blood sugar control. Occasionally, metformin, GLP-1 receptor agonists, Dipeptidyl peptidase-4 inhibitors, or SGLT2 inhibitor are prescribed off-label to people with type 1 diabetes, although fewer than 5% of type 1 diabetics use these drugs. Lifestyle
Besides insulin, the major way type 1 diabetics control their blood sugar is by learning how various foods impact their blood sugar levels. This is primarily done by tracking their intake of carbohydrates – the type of food with the greatest impact on blood sugar.