What is Diabetes Melitus ?

What is it ?

Diabetes mellitus is a heterogeneous group of diseases that share blood sugar (hyperglycemia) so maintained.

How does it occur ?

In one type of pancreatic cells, beta cells, which produce the hormone insulin. Normally, the beta cells to produce and shed blood insulin continuously to figures ranging blood sugar and stay within limits. Insulin causes sugar to enter into all body tissues.

In situations in which increases the amount of blood sugar, for example, if we had an ice cream, beta cells secrete more insulin to deal with the high blood sugar, the more insulin causes the sugar to be taken up by the tissue and normalize blood sugar. Similarly, if we make a physical activity, for example, half an hour of swimming decrease beta cell insulin release manufacture and given that exercise tissues more easily grab the sugar and thus less amount of insulin need to have figures in normal sugar.

It is very important to keep blood sugar within these limits of “normal.” Very low blood sugar levels (hypoglycemia) make our food has no brain function, and similarly, very high levels (hyperglycemia) cause the brain to malfunction due to excessive sugar saturation. The normal blood sugar is set to values ​​of 70-110 mg / dl (= 3’9-6’1 mmol / L). 
There are two major types of diabetes depending on how hyperglycemia occurs: the deficiency insulin or manufacturing difficulty of the use of sugar or both tissues.

• Type 1 diabetes mellitus: In it there is a lack of insulin production by the beta cells of the pancreas due to destruction of such cells.
• Diabetes mellitus type 2: Initially there is a difficulty in the organs and tissues of the body to use sugar (organs and tissues are resistant to insulin action, is what is called “insulin resistance”). Then added the lack of insulin production by the beta cells.

There are also other less common forms of diabetes:

• Gestational Diabetes mellitus: As the name suggests is a diabetes during pregnancy in a woman who has no previous diabetes. It occurs in 4% of pregnancies. In the vast majority of women figures disappear high blood sugar after birth, but these women are at high risk for diabetes in the following years. So, could be considered as the initial stage of type 2 diabetes mellitus and where pregnancy could be the element that shows.
• Other forms of diabetes, more rare, are those due to genetic defects affecting the beta cell function or action of insulin, pancreatic injury (absence of beta cells from birth, chronic pancreatitis, pancreatic tumors , etc.) to drugs such as corticosteroids, hormones to the presence of anti-insulin action (acromegaly, Cushing’s syndrome, pheochromocytoma, glucagonoma), etc.

Before the onset of diabetes as such, before the appearance of hyperglycemia with typical symptoms (see below), the disease goes through a phase of slight changes in blood sugar and few or no symptoms due to increased sugar. In type 1 diabetes this phase is usually very short, so that rapidly produces hyperglycemia symptoms and diagnosis is made. In type 2 diabetes often go several years before the symptoms leading to the suspicion and diagnosis.

If we could see the individual with diabetes type 2 diabetes before it is instituted, we would observe that there is a first phase in which sugar figures are only slightly above normal in the blood, we speak of a disorder of glucose fasting. If that individual will submit to a sugar overload test (75 g glucose administered orally and determine the level of blood sugar 2 hours) at this time would still be normal. Later, the test would altered sugar overload, but the patient would not have symptoms or they would be very mild or slightly marked; speak of impaired glucose tolerance. These states could define as prediabetes. At a later stage symptoms appear due to sustained hyperglycemia and, if done a blood test, sugar is persistently high (not necessarily very high), we arrive at the stage of overt diabetes.

It is important to identify these patients with abnormal sugar but still without a diagnosis of diabetes presented because, more often than the general population, the complications seen in diabetes: hypertension, abnormal blood fats, more likely to thrombosis and especially cardiovascular disease and death by it. A percentage of these prediabetic individuals progress to clinical diabetes in the next 10-15 years, but some do not progress to diabetes or even revert to normal, especially if you lose weight and improve their lifestyle (mainly in terms to diet and physical activity). 
Diabetes mellitus affects a large number of people worldwide. Approximately 3-6% of the Spanish population is diabetic. The most common is type 2 diabetes mellitus.

In both types of diabetes (type 1 and type 2) there is a genetic predisposition to developing the disease, to which must be added to environmental factors that are present illness. In type 1 diabetes mellitus is, in most cases the presence of antibodies in a blood that are directed selectively against pancreatic beta cells, these antibodies are called ICA. It is believed that in individuals with genetic predisposition, the onset of an environmental factor, for example, a viral infection, trigger the production of antibodies. Soon these antibodies will destroy beta cells and thus will trigger the onset of hyperglycemia and the associated symptoms, namely diabetes and immediate need for insulin therapy. 
In type 2 diabetes mellitus, genetic predisposition is the main factor related to their appearance. On this strong genetic component, there are environmental factors (such as obesity, poor diet and lack of physical activity) that facilitate the development of the disease. The first thing that appears is the resistance of the tissues (liver, muscle and fat tissue) to insulin action: although no insulin, it fails to normalize blood sugar numbers. Accordingly, the beta cells of the pancreas to synthesize and release more insulin blood, which normalize the sugar initially achieved. With the passage of time (years) beta cells end up being unable to cope with this “insulin resistance” of the tissues. When this occurs are clear symptoms of diabetes.

As we have seen, insulin has a key effect on the metabolism of carbohydrates, their absence causes increased blood sugar. Insulin but also controls metabolism of fats and proteins. Insulin deficiency is accompanied by increased triglycerides and decreased HDL cholesterol.