Types of Diabetes
Diabetes Mellitus is the term used to describe a chronic disease caused by relative or complete decrease in production and secretion of insulin by pancreatic beta-cells, or by the diminished effectiveness of secreted insulin in consequence of the gradual loss of insulin sensitivity of target cells (insulin resistance).
Diabetes mellitus is characterized by abnormally high concentration of blood glucose. A fasting
plasma glucose concentration of ≥7.0 mmol/L (126 mg/dL) or 2-h plasma glucose level of ≥ 11.1mmol/L (200 mg/dL) is set for the diagnosis of Diabetes according to WHO guidelines.
Without proper management Diabetes can lead to various complications such as cardiovascular disease, kidney failure, blindness and nerve damage:
- Diabetes is the main cause of partial vision loss and legal blindness in adults in developed countries. Furthermore, Diabetes accounts for the majority of limb amputations that are not the result of an accident.
- People with Diabetes are much more likely to suffer a heart attack or stroke and are at greater risk of developing kidney disease.
The most common types of Diabetes are type 1 and type 2.
Insulin is given as a substitute (type 1) or a supplement (type 2) to endogenous insulin secretion.
At present, Diabetes is incurable, but symptomatic treatment exists.
Type 1 Diabetes
Type 1 Diabetes is the insulin-dependent, immuno-mediated or juvenile-onset form of Diabetes. It is caused by an auto-immune reaction where the body´s defence system attacks the insulin-producing pancreatic beta-cell and leads to their rapid demise.
Genetic and environmental factors could trigger the development of type 1 Diabetes.
Type 1 Diabetes results from pancreatic beta-cell destruction, usually leading to the absolute loss of insulin production and secretion.
The onset of type 1 Diabetes is usually sudden and dramatic.
The treatment of type 1 Diabetes patients consists of insulin replacement by exogenous insulin. Patients with this form of Diabetes need insulin injections every day in order to control the blood glucose level.
LADA (Latent Autoimmune Diabetes in Adults)
This atypical form of type 1 Diabetes presents initially like type 2 Diabetes, but progresses to insulin dependency within months or a few years.
Type 2 Diabetes
Type 2 Diabetes is the non-insulin dependent Diabetes or adult-onset Diabetes.
Type 2 Diabetes results from a progressive demise of pancreatic beta-cells, caused by the insulin resistance of insulin target cells. As a result of increasing insulin resistance and reduced insulin secretion over time because of diminished beta-cell mass, the average blood glucose level rises unrelentingly and supplemental insulin injections may be needed with disease progression.
Type 2 Diabetes comprises 90-95 % of people with Diabetes worldwide, and is largely the result of excess body weight and physical inactivity:
- Over 80 % of people with type 2 Diabetes are overweight.
- People who do not lead an active life are more at risk of developing type 2 Diabetes.
- People are more at risk if there is a history of Diabetes in close family members.
This type of Diabetes occurs in people over the age of 45 years but is now also affecting children and adolescents to a greater extent as a consequence of increased obesity among the young.
Symptoms of type 2 Diabetes patients are usually less obvious. The onset of type 2 Diabetes is gradual and therefore hard to detect. It is estimated that more than 50 % of adults with type 2 Diabetes are not aware of their disease and may have Diabetes for several years before symptoms are recognised.
The treatment of type 2 Diabetes is in line with the progressive nature of the disease. Type 2 Diabetes treatment consists of diet and exercise measures, oral antidiabetics, insulin and combinations thereof. Usually, type 2 Diabetes patients can control the blood glucose level by lifestyle changes aimed at weight control and increased physical activity at the onset of the disease.
MODY (Maturity-Onset Diabetes of the Young)
MODY is a kind of type 2 Diabetes of the young that accounts for 1-5 percent of people with Diabetes. Of the six forms identified, each is caused by a defect in a single gene, which negatively modifies the insulin secretion of pancreatic beta-cells.