Diabetics know that if they don’t keep their sugar levels down, they will suffer from diabetic complications. One of these complications is peripheral neuropathy.
Diabetics often present with a tingling or numb sensation in the feet and toes and this indicates that there is already some level of peripheral neuropathy, a loss of nerve function. Because the nerves no longer function correctly, the diabetic patient feels unusual sensations, sometimes hot or cold, sometimes a numbness.
Because the patient can no longer feel their toes, the likelihood of undetected damage increases and this is the major cause for concern. Diabetics typically take longer to heal and so even a small cut can develop into an infected sore which will not heal. In some cases it can lead to amputation of the toe or even the foot.
Often the peripheral neuropathy is worse at night or early morning.
Autonomic neuropathy is where the nerves affected control blood pressure, bowel and bladder functions, sexual response, and perspiration. Often this form is not obvious when diabetics present for diagnosis but it has systemic consequences.
Where the vagus nerve is affected, this can influence the cardiac response as well as the lungs and digestion. In addition, the immune reaction can be affected.
Research into these specific factors associated with diabetes has not been as extensive as the investigation into methods of controlling blood sugar. But there are indications that bringing down the blood sugar level substantially, can improve vagus nerve response.
A third form of neuropathy is called proximal neuropathy and gives rise to pain in the thighs, hips, buttocks as well as causing muscle weakness. Many diabetics experience apparently random muscle pains and take pain killers to manage it but a far better method is to reduce blood glucose levels.
There is a growing body of evidence that such diabetic symptoms can be greatly reduced or even eliminated by strict blood glucose control.
This form appears without warning and affects particular nerves often in the head, torso or leg. A sudden inability to focus the eyes or aching can occur, or the patient might experience double vision which can be dangerous if they are working with machinery or driving.
Some patients experience sudden pain in the thigh or the calf muscles, and where the pain affects the chest it can make the patient worry that it is heart disease.
Such pains do not seem to cause long term damage in themselves but they are distressing and painful. The tendency is to use painkillers to manage them but once again strict control of blood glucose is more effective.
Many diabetics are only aware of the peripheral neuropathy and underestimate the importance of the other forms which have system-wide consequences. But these do show signs of improvement when blood glucose levels are consistently reduced.
What are the causes?
Although the research is continuing into the causes of neuropathy, there are certain factors that are known to be important. High blood glucose over a long period of time is almost always present, and there is associated damage to the blood vessels carrying oxygen to the peripheral nerves.
Other factors such as genetics, smoking, mechanical injury and autoimmune illnesses also see an associated increase in peripheral neuropathy but there is a clear connection with diabetes.
Is it reversible?
There has been a lot of debate about whether restoring blood glucose to low levels will bring about a reversal in peripheral neuropathy. Some authorities, such as Dr Richard Bernstein, argue strongly that it is possible and he has seen numerous cases amongst his patients of improvements.
But others argue that where the damage is too extensive, the nerves do not regenerate and the effect is permanent. But since the blood sugar levels recommended by most doctors for diabetics are outside of the normal range, there is little controlled evidence of the effects on diabetic peripheral neuropathy of getting back to truly normal blood sugar levels.