Insulin therapy is about 80 years old. In 1922, Canadian F. Bunting and Englishman J. McLeod first isolated insulin and proposed it for the treatment of diabetes mellitus. This Nobel Prize-winning discovery prevented many millions of deaths. Insulin is one of those drugs that can really be called life-saving.
The main indications for insulin therapy:
- type 1 diabetes mellitus;
- type 2 diabetes mellitus — according to indications, which are discussed separately below;
- diabetes mellitus in pregnant women (gestational diabetes) if it is impossible to compensate for it with diet therapy;
- diabetes mellitus in chronic pancreatitis with pancreatic insufficiency.
Insulin therapy goals:
- normalize carbohydrate metabolism. The best option is to normalize the fasting blood glucose level and prevent its excessive increase after a meal, exclude hyperglycemia, glucosuria and hypoglycemia; a satisfactory option is to achieve the elimination of the symptoms of diabetes, excessive hyperglycemia, pronounced and frequently occurring hypoglycemia, as well as ketosis;
- to normalize fat (lipid) and protein metabolism;
- to ensure the possibility of adequate nutrition while maintaining a normal body weight;
- to prevent the development of vascular, renal and other chronic complications of diabetes mellitus or to minimize them;
- to improve the quality of life of patients, including the possibility of a lifestyle that is as close as possible to normal and free.
Insulin therapy is aimed at bringing the content of the active form of this hormone in the body to those levels that are typical for a healthy person during the day. Normally, an adult’s pancreas secretes 35-50 units (U) of insulin per day, which is 0.6-1.2 U per 1 kg of body weight. 1 Unit of insulin is equal to 36 micrograms (mcg) or 0.036 mg. Insulin secretion is divided into basal (main) and food.
- Basal insulin secretion ensures optimal levels of glycemia and metabolism between meals and during sleep. Basal insulin accounts for 40-50% of daily insulin production.
- Nutritional insulin secretion matches the postprandial rise in blood glucose, allowing post-meal hyperglycemia to be neutralized and carbohydrates absorbed. In the medical literature, post-nutritional hyperglycemia is referred to as postprandial hyperglycemia.
The amount of “food” insulin approximately corresponds to the amount of digestible (that is, excluding dietary fiber) carbohydrates consumed — about 1 — 1.5 U per 10-12 g of carbohydrates. The “food” insulin accounts for at least 50 — 60% of the daily production of this hormone.
Insulin secretion is subject to physiological daily fluctuations: the need for insulin increases in the early morning hours (from about 4:00), and then it gradually decreases during the day. Therefore, during breakfast hours, 1.5 — 2.5 U of insulin is secreted for 10-12 g of digestible carbohydrates, and for the same amount of carbohydrates in the afternoon hours of lunch and evening hours of dinner — respectively 1.0-1.2 and 1.1 — 1.3 units The indicated values of insulin secretion, despite their approximate nature, are of great importance for insulin therapy.