Type 1 Diabetes – a Very Challenging Disease
The word diabetes originated from the Greek verb diabainein, dia meaning ‘across’ and bainein meaning ‘to stand’. Altogether the word means ‘to stand with legs as under’. Thus, the meaning of diabetes came out as ‘siphon’ indicating the tendency for excessive urination (polyuria) in diabetes.
Incidence & etiology
5 – 10% of the diabetic population of the world suffers from Type 1 Diabetes (IDDM). Type 1 diabetes generally occurs in the younger age group below 16 – 18 years of age. It is said that each year the incidence is increasing by 2 – 5 %.
Insulin, the absence of which is the cause of this type of diabetes, is secreted from the islets of Langerhans (pancreatic β cells) comprising 1-2% of the pancreatic mass. Complete destruction of the pancreatic β cells leads to insulin deficiency. There are two types of type 1 diabetes; type 1A which results from an auto immune attack on the pancreatic β cells. The cause of type 1B is unknown.
Diabetes has a hereditary component associated with it. The hereditary susceptibility is predominantly determined by the HLA genotypes DR and DQ. This accounts for 50% of the genetic susceptibility. 15% of the genetic susceptibility is contributed by insulin-VNTR (IDDM2) and CTLA4 (IDDM12). The autoimmune reaction is triggered when the genetic susceptibility coincides with environmental triggers like coxsackie virus, enteroviruses, rubella environmental toxins like nitrosaminonitrans. It has been said that early exposure to cow’s milk, proteins, cereals, gluten coupled with the genetic susceptibility in an individual, can lead to Type 1 diabetes.
The T-cell mediated autoimmune response leads to insulitis and progressive destruction of β cells.
Normal fasting plasma glucose is in the range of 5.5mmol/L or below.
When the blood glucose levels are elevated for long periods of time, glycosylation of haemoglobin molecule occurs. The level of HbA1c should be between 7.5-8.5% for children below six years of age. It should be less than 8% for children between 6-12 years and it should be less than 7.5% for children between 13-19 years. For adults the HbA1c levels should be less than 7%.
Appropriate dosage of insulin should be delivered. Proper and regular monitoring of plasma glucose levels should be done. The HbA1c levels should be monitored in case of controlled diabetes every six months and in case of uncontrolled diabetes every 3 months. Dietary modification programmes should not be so rigid that it becomes difficult to follow the regime. Instead the modifications should be flexible and easy to follow. Severe hypoglycaemia and diabetic ketoacidosis should be avoided. Treatment of an associated thyroid dysfunction and coeliac disease should definitely be done.
Microvascular complications of diabetes include retinopathy, nephropathy and neuropathy. Hyperlipidaemia and hypertension are a part of macrovascular complications of diabetes.
Facing the challenges
Replacement of islet cells should be considered as one of the challenges of recent times. There are several complications of the procedure like bleeding, mouth ulcers, anaemia, diarrhea and ovarian cysts. Stem cells can be thought to be as potential source of islet cells but such research work is still in the preliminary stage.