Overview of diabetic neuropathy
Diabetic neuropathy is a common and serious complication of type 1 and type2 diabetes. It is a type of nerve damage caused by long-term high blood sugar levels. The condition typically develops slowly, sometimes over the course of several decades.
If you have diabetes and notice numbness, tingling, pain, or weakness in your hands or feet, you should see your doctor. These are early symptoms of peripheral neuropathy. The danger is usually when you can’t feel pain and an ulcer develops on your foot.
There are different types of diabetic neuropathy that affect different areas of your body and cause a variety of symptoms. If you have diabetes, it is significant to regularly check your blood glucose levels and contact your physician if you have any symptoms of neuropathy.
Peripheral neuropathy can cause a loss of feeling in the feet. Four main types of neuropathy can affect the nervous system, including:
- Autonomic neuropathy – occurs in the nerves that control involuntary body functions, such as digestion, urination, or heart rate.
- Neuropathy of the thoracic and lumbar root, or proximal: it damages the nerves along with a specific distribution of the body, such as the chest wall or the legs.
- Mononeuropathies: can affect any individual nerve.
What are the symptoms of diabetic neuropathy?
The signs and symptoms of diabetic neuropathy typically take several years to appear. Signs and symptoms will depend on the type of neuropathy and nerves it affects.
Symptoms vary depending on the areas affected. Common signs and symptoms of the different types of diabetic neuropathy include:
- Sensitivity to touch
- Loss of sense of touch
- Difficulty with coordination when walking
- Numbness or pain in your hands or feet
- Burning sensation in feet, especially at night
- Muscle weakness or wasting
- Bloating or fullness
- Vaginal dryness
- Erectile dysfunction
- Inability to sense low blood glucose
- Vision trouble, such as double vision
- Increased heart rate
What causes diabetic neuropathy?
Diabetic neuropathy is caused by high blood sugar levels sustained over a long period of time. Other factors can lead to nerve damage, such as:
- Damage to the blood vessels caused by high cholesterol levels.
- Mechanical injury, such as injuries caused by carpal tunnel syndrome.
- Lifestyle factors, such as smoking or alcohol use.
Low levels of vitamin B-12 can also lead to neuropathy. Metformin, a common medication used to manage diabetes, can decrease levels of vitamin B-12. You can ask your doctor for a simple blood test to identify any vitamin deficiencies.
How common is diabetic neuropathy?
Although different types of diabetic neuropathy can affect people who have diabetes, research suggests that up to half of people with diabetes have peripheral neuropathy. More than 30 per cent of people with diabetes have autonomic neuropathy.
Though less than 10 per cent of people with diabetes experience symptoms of carpal tunnel syndrome, about 25 per cent of people with diabetes have some nerve compression in the wrist. Other focal neuropathies and proximal neuropathy are less common.
How is diabetic neuropathy diagnosed?
The diagnosis will be made based on your individual symptoms and a physical exam. The doctor can evaluate your blood pressure, heart rate, strength, reflexes, and sensitivity. Foot exams are recommended for all diabetics. Other tests may be applied, such as:
- Nerve conduction studies
- MG (electromyography) and
- QST (quantitative sensory test)
- Doctors should screen diabetic patients for neuropathy at least once a year.
In an annual checkup, the neuropathy test will involve the doctor stimulating the foot with a small plastic instrument or tuning fork to see if it is correctly detecting the sensation. Tests to confirm or monitor a current neuropathy may include ultrasound, nerve studies, and biopsies, or referral to a professional neuropathy consultant who can perform further tests.
How is diabetic neuropathy treated?
While diabetic neuropathy cannot be cured, there are treatments available to help control some of the symptoms. Another goal of treatment is to keep blood glucose levels under good control through a combination of diet and medications so that the neuropathy does not get worse. Keeping blood glucose levels under control has been shown to improve symptoms and prevent pain from getting worse.
Diabetic neuropathy risk factors
Anyone who has diabetes can develop neuropathy. But these risk factors make nerve damage more likely:
- Poor blood sugar control. Uncontrolled blood sugar puts you at risk for all the complications of diabetes, including nerve damage.
- History of diabetes. Your risk of diabetic neuropathy increases the longer you have diabetes, especially if your blood sugar is not well controlled.
- Nephropathy Diabetes can damage the kidneys. Kidney injury sends toxins into the blood, which can principal to nerve damage.
- Being overweight. Having a body mass index (BMI) of 25 or more can increase your risk of diabetic neuropathy.
- Smoking. Smoking narrows and hardens the arteries, reducing blood flow to the legs and feet. This makes it difficult for wounds to heal and damages peripheral nerves.
Diabetic neuropathy complications
Diabetic neuropathy can cause several serious complications, including:
- Hypoglycemia unawareness. Blood sugar levels below 70 milligrams per deciliter (mg/dL) normally cause shakiness, sweating and a fast heartbeat. But if you have autonomic neuropathy, you may not notice these warning signs.
- Loss of a toe, foot or leg. Nerve damage can make you lose feeling in your feet, so even minor cuts can turn into sores or ulcers without your realizing it. In severe cases, an infection can spread to the bone or lead to tissue death. Removal (amputation) of a toe, foot or even the lower leg may be necessary.
- Urinary tract infections and urinary incontinence. If the nerves that control your bladder are damaged, you may be unable to fully empty your bladder. Bacteria can build up in the bladder and kidneys, causing urinary tract infections. Nerve damage can also affect your ability to feel when you need to urinate or to control the muscles that release urine, leading to leakage (incontinence).
- Sharp drops in blood pressure. Damage to the nerves that control blood flow can affect your body’s ability to adjust blood pressure. This can cause a sharp pressure drop when you stand after sitting, which may lead to dizziness and fainting.
- Digestive problems. If nerve damage strikes your digestive tract, you can have constipation or diarrhoea, or both. Diabetes-related nerve damage can lead to gastroparesis, a condition in which the stomach empties too slowly or not at all, which causes bloating and indigestion.
You can prevent or delay diabetic neuropathy and its complications by closely monitoring your blood sugar level and taking good care of your feet.
Managing blood sugar
The American Diabetes Association recommends that people with diabetes get an A1C test at least twice a year. This test calculates your average blood sugar level for the past two to three months. A1C goals may need to be adapted, but for many adults, the American Diabetes Association recommends an A1C of less than 7%. If your blood sugar levels are higher than your goal, you may need changes in your daily management, such as adding or adjusting your medications or changing your diet.
Foot problems, with sores that don’t heal, ulcers, and even amputation, are shared complications of diabetic neuropathy. But you can prevent many of these problems by getting a complete foot exam at least once a year, having your doctor check your feet at every visit, and taking good care of them at home. Follow your doctor’s recommendations for good foot care. To protect the health of your feet:
- Check your feet every day. Look for blisters, cuts, bruises, cracked and peeling skin, redness, and swelling. Use a mirror or ask a friend or family associate to help you examine the parts of your feet that are hard to see.
- Keep your feet clean and dry. Wash your feet every day with warm water and slight soap. Avoid getting your feet wet. Dry your feet and between your toes carefully.
- Hydrate your feet. This helps prevent cracking. But don’t put lotion between your toes, as it could stimulate fungal growth.
- Wear clean, dry socks. Look for socks made of cotton or moisture-wicking fibres that do not have tight bands or heavy seams. Wear padded shoes that fit well. Always wear shoes or slippers to defend your feet. Make sure your shoes fit well and allow your toes to wiggle. A foot doctor can teach you how to buy shoes that fit well and prevent problems like corns and calluses.