Diabetes Mellitus type 2 otherwise known as Non-insulin dependent diabetes mellitus (NIDDM) results from reduced insulin sensitivity or the inability to secrete insulin. It usually occurs in older adults and is the most common form of diabetes mellitus. It is progressive and patients eventually require the use of injected insulin rather than treatment with oral drugs.
The on-set of NIDDM is influenced by genetic and environmental factors and its prevalence is increasing worldwide, particularly in developing countries. It also increases the risk of other diseases such as cardiovascular disease retinopathy and stroke.
Once carbohydrates are broken down to form glucose it needs to pass into the body cells that need it, but it cannot cross through the cell membrane itself. Insulin must bind to proteins (receptors) in the cell membranes. This triggers a mechanism that allows the glucose to be transported inside the cell.
In NIDDM glucose cannot be transported into the cells due to either the inability of the pancreas to produce enough insulin or an abnormal receptor on the cell membrane that prevents insulin from binding. If insulin can’t bind to the receptor the glucose is prevented from being transported inside the cell. This leads to insulin resistance.
Insulin resistance therefore means that insulin is present but can’t be put to use. It requires higher than normal levels of circulating insulin before a normal effect can be seen.
The role of leptin in NIDDM is unclear but leptin levels are found to be high with this disease. Insulin is known to enhance leptin production.
Resistance exercise is known to reduce the effect of insulin resistance and risk of developing NIDDM. When exercise begins the body increases and maintains the blood glucose levels to provide fuel for the exercising muscles.
Adrenaline is also released during exercise. It increases heart rate to cope with the demand for oxygen. Adrenaline also suppresses insulin secretion so that more insulin stays in the blood ready for use.
If the diabetic patient has high levels of insulin while exercising then the adrenaline cannot reduce the insulin levels enough. So blood glucose levels may drop too far and cause hypoglycaemia.
Therefore exercise may prove to be a problem for diabetic sufferers. However it has been noted that if patients undergo an exercise regime for as little as one week insulin sensitivity is improved.
Metformin is given orally to treat NIDDM. Insulin sensitivity is improved so glucose use is increased.
It is possible to reduce the risk of developing NIDDM if certain lifestyle changes are made. According to the National Institute for Health and Clinical Excellence there are 1.6million people diagnosed with diabetes mellitus in England and Wales. 85% of these people have NIDDM.
It has been estimated that 5% of the healthcare budget is spent on care for NIDDM sufferers. 10% of hospital budgets are spent on caring for these patients and treating the complications brought about by poor management of the disease.
Complications of diabetes mellitus include renal disease, retinopathy, cardiovascular disease, stroke and limb amputation. All of which may be prevented or delayed, freeing up bed space and reducing waiting times on hospital waiting lists.
NIDDM is most prevalent in developed countries and is increasing in others where lifestyle changes are becoming more sedentary. Research shows that genetic and environmental factors both play a part in the disease. However risk of developing NIDDM or insulin resistance can be reduced if obesity is avoided and regular exercise is taken.
Regular monitoring at doctors clinics also has a beneficial effect by encouraging patients to adopt the preventative measures required and also allows management of patients to prevent onset of complications at are so costly to treat.