Pathophysiology of Diabetes Mellitus

What is Diabetes Mellitus

Diabetes mellitus (DM) or simply diabetes, is a chronic health condition in which the body either fails to produce sufficient amount of insulin or responds abnormally to insulin. Speaking about the classification of diabetes mellitus, it is of three types, namely, Type 1 diabetes, Type 2 diabetes and Gestational diabetes. The ultimate outcome for all three types of diabetes is high blood glucose level or hyperglycemia. The pathophysiology of diabetes mellitus is very complex, as the disease is characterized by different etiologies but share similar signs, symptoms and complications.

Diabetes Mellitus and Pathophysiology

The pathophysiology of diabetes mellitus (all types) is related to the hormone insulin, which is secreted by the beta cells of the pancreas. This hormone is responsible for maintaining glucose level in the blood. It allows the body cells to use glucose as a main energy source. However, in a diabetic person, due to abnormal insulin metabolism, the body cells and tissues do not make use of glucose from the blood, resulting in an elevated level of blood glucose or hyperglycemia. Over a period of time, high glucose level in the bloodstream can lead to severe complications, such as eye disorders, cardiovascular diseases, kidney damage and nerve problems.

In Type 1 diabetes, the pancreas cannot synthesize enough amount of insulin hormone as required by the body. The pathophysiology of Type 1 diabetes mellitus suggests that it is an autoimmune disease, in which the body's own immune system generates secretion of substances that attack the beta cells of the pancreas. Consequently, the pancreas secretes little or no insulin. Type 1 diabetes is more common among children and young adults (around 20 years). Since it is common among young individuals and insulin hormone is used for treatment, Type 1 diabetes is also referred to as Insulin Dependent Dabetes Mellitus (IDDM) or Juvenile Diabetes.

In case of Type 2 diabetes mellitus, there is normal production of insulin hormone but the body cells are resistant to insulin. Since the body cells and tissues are non responsive to insulin, glucose remains in the bloodstream. It is commonly manifested by middle-aged adults (above 40 years). As insulin is not necessary for treatment of Type 2 diabetes, it is known as Non-insulin Dependent Diabetes Mellitus (NIIDM) or Adult Onset Diabetes.

Gestational diabetes, on the other hand, occurs among pregnant women. It is caused due to fluctuations of the hormonal level during pregnancy. Usually, the blood glucose level returns to normal after the baby is born.

As already mentioned above, the symptoms and effects of all the three forms of diabetes are similar. The noticeable manifested symptoms include increased thirst (polydipsia), increased urination (polyuria), increased appetite (polyphagia), excessive fatigue, unexplained weight loss and body irritation. Regarding the definition of diabetes mellitus, it is often described as a fasting blood glucose level of 126 milligrams per deciliter (mg/dL) or more. As per statistics, Type 2 diabetes is the most commonly occurring type, in comparison to the other two forms of diabetes mellitus.

Early and correct detection of the type of diabetes is necessary to prevent severe health effects. After diagnosis, a physician may prescribe appropriate medication for treatment of diabetes, which could include insulin injections or oral insulin medicines, depending upon the type of diabetes mellitus. In addition, healthy lifestyle modifications, especially diet and exercise are recommended for the effective management of symptoms and long-term effects. Since diabetes is a global health issue, studies regarding the pathophysiology of diabetes mellitus are currently in progress in order to minimize its associated health effects.