What is neuropathy?
Neuropathy is one of the long-term complications which affects the nerves. Nerves carry messages between the brain and every part of our bodies, making it possible to see, hear, feel and move. Nerves also carry signals that we are not aware of to parts of the body such as the heart, altering the rate it beats at, and the lungs, so we can breathe. Therefore, damage to the nerves can cause problems in various parts of the body.
Diabetes can cause neuropathy as a result of high blood glucose levels damaging the small blood vessels which supply the nerves. This prevents essential nutrients reaching the nerves. The nerve fibres are then damaged or disappear.
There are three different types of neuropathy: sensory, autonomic and motor.
Sensory neuropathy affects the nerves that carry messages of touch, temperature, pain and other sensations from the skin, bones and muscles to the brain. It mainly affects the nerves in the feet and the legs, but people can also develop this type of neuropathy in their arms and hands.
Symptoms can include:
- Tingling and numbness
- Loss of ability to feel pain
- Loss of ability to detect changes in temperature
- Loss of coordination – when you lose your joint position sense
- Burning or shooting pains – these may be worse at night time.
The main danger of sensory neuropathy for someone with diabetes is loss of feeling in the feet, especially if you don’t realise that this has happened. This is dangerous because you may not notice minor injuries caused by:
- Walking around barefoot
- Sharp objects in shoes
- Friction from badly fitting shoes
- Burns from radiators of hot water bottles.
If ignored, minor injuries may develop into infections or ulcers. People with diabetes are more likely to be admitted to hospital with a foot ulcer than with any other diabetes complication.
Charcot joint is a rare complication of people with diabetes who have severe neuropathy. It happens when an injury to the foot causes a broken bone, which may go unnoticed because of the existing neuropathy. The bone then heals abnormally, causing the foot to be come deformed and misshapen. Treatment includes immobilizing the foot in a plaster cast and in some cases surgery.
Autonomic neuropathy affects nerves that carry information to your organs and glands. They help to control some functions without you consciously directing them, such as stomach emptying, bowel control, heart beating and sexual organs working.
Damage to these nerves can result in:
- Gastroparesis – when food can’t move through the digestive system efficiently. Symptoms of this can include bloating, constipation or diarrhoea
- Loss of bladder control, leading to incontinence
- Irregular heart beats
- Problems with sweating, either a reduced ability to sweat and intolerance to heat or sweating related to eating food (gustatory)
- Impotence (inability to keep an erection).
Motor neuropathy affects the nerves which control movement. Damage to these nerves leads to weakness and wasting of the muscles that receive messages from the affected nerves. This can lead to problems such as:
- muscle weakness, which could cause falls or problems with tasks such as fastening buttons.
- muscle wasting, where muscle tissue is lost due to lack of activity
- muscle twitching and cramps.
How is neuropathy treated?
There are many treatments available to relieve the symptoms caused by neuropathy. This may include medication for nausea and vomiting, painkillers for sensory neuropathy or treatment to help with erectile dysfunction. Good control of blood glucose levels can improve the symptoms of neuropathy and can reduce the progression of the nerve damage.