Diabetes is a Greek word which means “siphon of urine”, “Dia=through”, “Betes=to go” which refers to the increased passage of urine. Mellitus is also derived from a Greek word which means “sweetened with honey”.
Diabetes Mellitus is the name given to a group of metabolic disorders, where all of them share the common feature of “Hyperglycaemia” (i.e., increased blood glucose levels). This is a metabolic as well as endocrine disorder. The disorder here is alteration in the metabolism of glucose.
This disease has its roots in the ancient times. Aretaeus, a scientist in 2nd century C.E., told that Diabetes Mellitus was due to melting down of the flesh and limbs of the person into his urine which was most commonly seen in women. He also told that the patient affected with Diabetes had to suffer a painful, short life with unquenchable thirst and a large amount of micturition (excessive secretion of water from the body with incessant flow).
Diabetes is broadly classified into two types based on the underlying cause or pathology.
The two types are:
1. Type 1 Diabetes.
2. Type 2 Diabetes.
Other types of Diabetes are Gestational Diabetes, Diabetes due to other specific causes like Drugs, Endocrinopathies, Infections, Exocrine Pancreatic Defects, Genetic defects of Beta cell function, Genetic defects in Insulin action etc.
TYPE 2 DIABETES:
Type 2 Diabetes is also called “NIDDM- Non Insulin Dependent Diabetes Mellitus”. It is also sometimes called “Adult-Onset Diabetes Mellitus”.
It is the most common form of Diabetes seen in the effected (Diabetic) people. Nearly 90-95% of known Diabetics are of Type 2. It is seen in adults above 35 years of age. The underlying Pathology of Type 2 Diabetes is Insulin Resistance and Beta-cell Dysfunction. Though it has been named adult onset diabetes, its prevalence in children and adolescents is increasing at an alarming pace.
Insulin Resistance is the failure of the target tissues to respond normally to insulin. Beta cell dysfunction refers to the inability of beta cells to adapt to the long term demands of peripheral insulin resistance.
Type 2 Diabetes may or may not be associated with ketosis, i.e. it may be Ketosis prone mostly in obese and Ketosis resistant mostly in the lean and thin persons.
CAUSES AND GENETIC BACKGROUND:
The most common cause for it is Obesity. Even sedentary lifestyle also leads to it. Type 2 Diabetes is also caused because of genetic background. If both the parents are effected then the risk of getting diabetes in the offspring reaches nearly 40%. Latest researches have identified more than a dozen susceptible loci on the genes which lead to Type 2 Diabetes Mellitus. In case of identical twins the concordance of getting type II diabetes is nearly 70-90%.
Type 2 Diabetes Mellitus is multifactorial and polygenic. It depends on many factors like genetic factors and environmental factors like nutrition, physical activity etc. Its expression depends on all these factors.