Hyperglycemia is extremely harmful to the body, causing, in the long term, injury of various tissues and organs.
Although it is more common in children and adolescents, type 1 diabetes can also occur in adults.
What causes type 1 diabetes mellitus?
In most cases, type 1 diabetes is a disease of autoimmune origin in which the patient's own antibodies attack and destroy part of the pancreas, specifically the insulin-producing cells known as beta cells of the islets of Langerhans.
To understand what an autoimmune disease is, read: Autoimmune diseases .
The autoimmune process of destruction of beta cells of the pancreas occurs in genetically susceptible individuals and is probably triggered by one or more environmental agents, such as some types of virus.
The destruction process is slow and takes several months to a few years until enough cellular damage occurs so that insulin production becomes scarce.
There are two peaks in the incidence of diabetes, the first occurs between 4 and 7 years and the second between 10 and 14 years.
In summary, the patient is already born with the genetic alterations that favor the onset of type 1 diabetes, develops the autoantibodies in the first years of life and will only present the disease even in the middle to the end of childhood.
Type 1 diabetes of autoimmune origin is called type 1A. There is also type 1B diabetes, which is more rare, also occurs by destruction of beta cells of the pancreas, but the origin is unknown, with no autoantibodies involved in the genesis of the disease.
Is Type 1 Diabetes Hereditary?
Family history is relevant, but it is not strictly necessary. The risk of a child developing type 1 diabetes is:
0.4% if there is no family history.
1 to 4% if the mother is a type 1 diabetic.
3 to 8% if the father is a type 1 diabetic.
2 to 6% if one of the siblings has DM1.
30% if both parents have the disease.
30% if a twin brother (identical) has the disease.
In cases of type 2 diabetes mellitus (DM2), heredity is a much stronger risk factor, with more than 75% of patients presenting positive family history.
Contrary to what occurs in most cases of type 1 diabetes, type 2 diabetes mellitus does not have an autoimmune origin and occurs mainly in adults who are obese, sedentary and with a positive family history.
DM2 is a type of diabetes that occurs because of insufficient insulin action in the bloodstream. The pancreas produces insulin, but the tissues do not recognize its presence, preventing the glucose from entering into the cells, a process known as insulin resistance.
What is diabetes mellitus?
What are the symptoms of type 1 diabetes?
The symptoms of type 1 diabetes are usually caused by hyperglycemia. Are they:
Loss of bladder control during sleep (return to bed wetting).
Slow healing of wounds.
In some children, the first sign of diabetes may be a complication known as diabetic ketoacidosis.
Without insulin, the cells do not get the proper amount of glucose and need to use the body's fat stores as a source of energy. The breakdown of fats generates acidic substances, called ketone bodies, such as β-hydroxybutyrate and acetoacetate.
Excess ketoacids cause a drop in blood pH, which can acidify blood to fatal levels, which is why ketoacidosis is considered a medical emergency. About 80% of the deaths of diabetic children and adolescents are caused by ketoacidosis.
Ketoacidosis usually occurs when glycemia is very uncontrolled, usually with values above 500 mg / dl. Its most common signs and symptoms are
Complications of type 1 diabetes
Over the years, chronic hyperglycemia can cause injury to various tissues in the body. Among the organs most affected are the heart, blood vessels, nerves, eyes and kidneys.
The rate and severity of complications is directly related to blood sugar levels (glycemia). In the long run, the more uncontrolled glycaemia and the older the diabetes, the greater the risk of multiple diseases.
There are several complications of type 1 diabetes, some directly linked to chronic hyperglycemia, others related to the restrictions that the disease causes. Among the most common are:
Coronary artery disease (angina) .
Acute myocardial infarction .
Injury of the arteries of the lower limbs: can cause severe obstruction of the blood vessels of the legs and need limb amputation.
Diabetic neuropathy: injury of the peripheral nerves, usually of the feet and legs, causing tingling, numbness, burning or pain.
Damage to the nerves of the gastrointestinal tract, leading to problems such as nausea, vomiting, diarrhea or constipation.
Erectile dysfunction .
Diabetic nephropathy: kidney damage, causing chronic kidney failure and loss of large amounts of protein in the urine.
Diabetic retinopathy: injury of blood vessels of the retina, which can cause blindness.
Pregnancy complications: pre-eclampsia, miscarriage, fetal death, and birth defects.
Eating disorders such as bulimia and norexia nervosa .
Repeat infections such as vaginal candidiasis and urinary infection .
Emergence of other autoimmune diseases: autoimmune thyroiditis and celiac disease are the most common.
Diagnosis of type 1 diabetes
The diagnosis of DM1 is made through the blood dosage of glycemia or glycosylated hemoglobin.
Two blood tests, taken on different days, are required with at least one of the three criteria listed below:
Fasting glycemia above 126 mg / dl.
Glycemia at any time of day above 200 mg / dl.
Glycosylated hemoglobin (HbA1c) greater than 6.5%.
Once diabetes is diagnosed, the endocrinologist may also look for the presence of autoantibodies in the blood.
Treatment of type 1 diabetes mellitus
There is no cure for type 1 diabetes. Treatment is aimed at long-term glycemic control in order to reduce the incidence of complications.
The control of glycemia is done through several approaches, the most important being:
Regular insulin administration (up to 6 times a day).
Frequent monitoring of blood glucose by the patient.
Practice of physical exercises.
The goal of treatment is to keep the glycosylated hemoglobin value below 7%. For this, the patient should seek to maintain blood glucose before meals between 80 and 130 mg / dl and after meals below 180 mg / dl.
If the values are uncontrolled, the diet and dose of insulin should be reevaluated.
Because in type 1 diabetes the pancreas produces little or no insulin, patients need to replace natural insulin with artificial insulin, which can be given through regular injections throughout the day or through an insulin pump.
The level of insulin administered should be carefully defined according to the patient's diet and exercise habits. Insufficient amounts may not control glycemia and increase the risk of complications, while excessive amounts may cause hypoglycaemia .
The types of insulin most used are:
Rapid-acting insulin : It starts at about 15 minutes, peaks within 1 hour, and continues to work for 2 to 4 hours.
Types: Insulin glulisine (Apidra), insulin lispro (Humalog) and insulin aspartic (NovoLog).
Insulin of intermediate action : it starts of action with about 2 to 4 hours, reaches the peak with 4 to 12 hours and is effective for about 12 to 18 hours.
Types: NPH (Humulin N, Novolin N).
Long-acting insulin : It reaches the bloodstream several hours after injection and tends to decrease glucose levels quite evenly over a 24-hour period.
Types: insulin detemir (Levemir) and insulin glargine (Lantus).