What is Diabetes Mellitus & its Signs and Symptoms?

Diabetes Mellitus is one of the Most Common & Most Dreaded Metabolic Diseases

Diabetes Mellitus is a condition that affects a large number of people around the world.  Estimates suggest that more than 220 million people in the world are affected from it, and around 3.4 million people may be losing their life every year because of it. Ironically, a lot of people affected by it do not even know that they are suffering from such a condition, making Diabetes Mellitus the most dangerous silent killer of our times. Worst of all, the World Health Organisation projects that the number of people dying from Diabetes will double between 2005 and 2030, making it imperative that every person on this planet becomes aware about this condition.

What is Diabetes Mellitus?

Diabetes Mellitus is a disease of glucose metabolism, resulting from inadequate or defective insulin, or defective response to it by the body. To understand Diabetes Mellitus, one needs to be aware of the normal glucose cycle in the body.

Our bodies need glucose as source of all energy.  All forms of carbohydrates in food are digested in the intestines to produce glucose, which is then absorbed in blood and taken to different parts of the body. While some of it is immediately taken up by cells of the body and utilized there, the remainder is stored by liver and other parts for later needs, after conversion to another form called glycogen. This process of conversion of glucose to glycogen is facilitated by Insulin, a hormone produced by the Islet cells of Pancreas, and it is this effect of Insulin that regulates the level of glucose in blood. As soon as the blood glucose levels rise, Insulin is produced. This Insulin then stimulates the absorption of glucose and its conversion to glycogen, and prevents the blood glucose level from rising.

If there is insufficient production of Insulin or if the cells of the body do not properly respond to the Insulin that is produced, then, the body cells are unable to take up glucose from blood. As a result, all the glucose absorbed from the digested food in intestines keeps accumulating in blood, leading to a rise in blood glucose levels. When blood glucose exceeds a certain level, then glucose begins to get passed in urine, as kidneys are no longer able to hold it back. As a result, glucose is present in urine, and by its osmolar impact, it also drags a lot more water along with it, causing excessive urine formation or polyuria. This excessive loss of water leads to dehydration and thirst, so the affected person has a tendency to drink lots of water. 

Diabetes Mellitus is a disease resulting from defective glucose metabolism. In this condition there is either a deficiency of insulin in the body, requiring Insulin injections (hence also known as Insulin dependent or Type I Diabetes Mellitus), or the body does not respond properly to insulin, a condition known as Insulin Resistance, requiring various measures to reduce the need for Insulin (hence also known as Non-Insulin dependent or Type II Diabetes Mellitus). Both the conditions are marked by a high glucose level in blood which may be associated with the presence of glucose in urine. 

What are the Signs & Symptoms of Diabetes Mellitus

The common symptoms of Diabetes Mellitus are Polyuria (high frequency of urination), Polydipsia (high intake of water) and sometimes weight loss (especially in Type I Diabetes) in spite of a good appetite (known as Polyphagia).

These symptoms are far more commonly observed in cases of Type I Diabetes, which occurs in life earlier than Type II. Since type I affects within the first three decades of life, it is also termed as Juvenile Diabetes. In comparison, the Type II Diabetes usually occurs later in life, and is seldom marked by the classical symptoms of polyuria, polydipsia and polyphagia. People with Type II Diabetes may not observe any symptom for a long time, and it is not uncommon for them to discover their Diabetic status by accident during a routine test of blood or urine. Since, Type II Diabetes Mellitus accounts for almost 90% of Diabetes in the world, most affected persons may actually become aware of their symptoms, if any, only after they come to know that they have Diabetes.

Diabetes leads to a variety of acute and chronic complications, and sometimes the first symptoms that one observes may be related to them. The acute complications include Diabetic Ketoacidosis and Non Ketotic Hyperosmolar Coma, both life threatening conditions associated with deteriorating consciousness and finally coma. Chronic complications of Diabetes affect the kidney, eyes and nerves and may result in various symptoms related to them. Presence of Diabetes Mellitus also delays healing and recovery of infections. Hence, if a person has an ulcer that is not healing, or the infection is not subsiding in spite of heavy treatment with antibiotics, Diabetes must be ruled out before other measures are adopted.