Diabetes is a group of metabolic disorders characterised by high blood glucose resulting from defect in insulin secretion, insulin action or both.
There are two main types of diabetes: Type 1 and Type 2 besides few rare specific types. The commonest (95%) is Type 2 which is predominantly because of insulin resistance (the tissues do not respond effectively to insulin produced by pancreas), with relative insulin deficiency.
Type 1 (5%) is mainly because of absolute insulin deficiency due to destruction of the beta cells of the pancreas. When we use the term diabetes alone, it refers to Type 2.
Type 2 diabetes
- It is usually an insidious disorder with onset in middle adulthood.
- Most patients are asymptomatic (60%) and may be diagnosed during investigations or general check-up.
- Possible symptoms: Increased thirst, increased urination, increased hunger, weight loss, excessive tiredness, delayed healing of wounds, itching, tingling and numbness.
- There is strong genetic predisposition (one or both parents diabetic).
- It is probably lifestyle factors like sedentary lifestyle and overweight, which causes diabetes to manifest in individuals who have genetic predisposition.
Type 1 diabetes
- Absolute deficiency of insulin (probably auto immune)
- Generally affects children and young adults
- It is rare below one year or above 30 years of age
- Onset is generally abrupt
- Mostly are insulin dependent
- May present with diabetic ketoacidosis
Pre-diabetic refers to the level of high sugar, higher than normal but not high enough to be termed as diabetes. The importance of this condition lies in the fact that they identify the individuals who are at highest risk of developing diabetes in the future and should be the target for all preventive strategies.
Diagnostic criteria for diabetes (ADA & WHO guidelines)
- Fasting blood glucose > 125 mg/dl
- Two hour blood glucose > 200 mg/dl
- Symptoms of diabetes + casual blood sugar > 200 mg/dl
(Dr Ajay Agarwal is a consultant family physician, with several papers and books on health issues to his credit. He is also the recipient of Lt. Governor of Delhi’s ‘Distinguished Service Award’).
Health Matters is Dr Ajay Agarwal’s attempt to demystify diabetes and make it manageable. Send in all your queries to firstname.lastname@example.org. Dr Agarwal will answer them in next week’s post.