Neuropathy in diabetes
What is diabetic neuropathy?
Neuropathy in diabetes is also called diabetic nerve damage or diabetic neuropathy. People with diabetes mellitus can develop this complication, which can cause temporary or permanent damage to nerve tissue.
What causes neuropathy in diabetes?
Injury to the nerves in diabetes is caused by a low blood flow to nerve tissue and high blood sugar levels. Neuropathy is more likely to result if blood glucose levels are not managed correctly. It may also have already occurred before the diabetes was diagnosed and treatment begun.
How common is neuropathy in diabetes?
Some people with diabetes never develop neuropathy while others may develop this condition relatively early. Neuropathy is a relatively common complication of diabetes, with about 40 to 60 per cent of people with diabetes having a mild form and 5 to 10 per cent having severe symptoms. Like diabetic retinopathy (damage to the retina of the eye), it is often related to the length of time the person has had diabetes and the degree of blood glucose control.
Symptoms of neuropathy in diabetes
Some people with neuropathy in diabetes may have no symptoms, but others will experience some of the following symptoms (usually developed gradually over many years):
- pain or burning in the feet;
- numbness in the limbs;
- tingling;
- weakness or decreased sensation to a body part;
- complete loss of sensation to a body part;
- paralysis of body areas;
- shaking muscles and muscle contractions;
- diarrhoea or constipation;
- loss of bladder control;
- facial drooping (often seen with a drooping eyelid or mouth);
- changes in vision;
- dizziness;
- difficulty swallowing; and
- indigestion, nausea and vomiting.
Symptoms may vary depending on the nerve(s) affected. The nerves that are involved with the digestive system may be affected and the stomach will then take longer to empty, while the gallbladder slows or stops functioning normally. The person may suffer diarrhoea, especially at night, and this can alternate with periods of constipation. Other body systems may also be affected, causing a number of other problems, including:
- impotence and problems with ejaculation;
- low blood pressure when standing up (causing giddiness);
- damaged and swollen joints (generally this is painless);
- inability to empty the bladder completely; and
- inability to sweat or excessive sweating.
Peripheral neuropathy
Peripheral neuropathy affects the peripheries of the body — that is, the hands and feet. One of the most common forms of neuropathy involves a slight numbness and tingling sensation of the toes and feet and, occasionally, the fingers. It generally affects both sides of the body and may also cause aching or shooting pains in the feet and legs, especially at night.
Risk of injury
In more advanced cases of diabetic neuropathy, there is an increased risk of injury because of loss of sensation and/or motor function. When complete loss of sensation occurs in the feet, people may not be aware of injuries occurring to the feet and consequently fail to look after them properly. Because of poor circulation, many injuries in people with diabetes heal very slowly or not at all. Even minor injuries can lead to serious infection, ulcers and even gangrene, which may then mean the amputation of toes, feet and other infected parts.
Loss of temperature sensation is also a significant risk factor for injury in people with diabetes. This can result in a person being unaware that the bath water they are stepping into is scalding them. They may also be at risk of developing severe burns after sitting too close to a heater.
People with diabetes should always wear well-fitting shoes or some type of foot protection as much as possible. They need to check their feet every day to detect foot problems early, and should have regular foot checks by a doctor or podiatrist. Even very small injuries should be attended to immediately to prevent the development of serious infections.
Treatment of neuropathy in diabetes
The treatment of neuropathy in diabetes usually involves strict control of blood glucose levels, with intensive insulin treatment often being needed to attain an adequate degree of control. Tight control of the amount of glucose in the bloodstream has been shown to reduce the risk of neuropathy.
Pain
Although diabetic neuropathy often causes loss of sensation, it can sometimes cause pain, especially in the feet and legs. This pain is often distressing, particularly at night when it can prevent sleep. Unfortunately, conventional analgesics are not often useful in this type of pain, and other types of medications may be needed. Your doctor will be able to discuss these pain relief options with you.
Last Reviewed: 14 September 2009
