7 of 10 people with diabetes suffer from some form of diabetic neuropathy. It is the most common complication of the disease. Neuropathy is a family of nerve disorders that affects every organ system including the feet, legs, arms and hands, digestive tract, heart, and sex organs. Some people with diabetic neuropathy have no symptoms; many others have symptoms such as pain, tingling, or numbness and loss of feeling in the hands, arms, feet, and legs. Depending on the affected nerves you can also have problems with your digestive system, urinary tract, blood vessels and heart. For some people, these symptoms are mild; for others, diabetic neuropathy can be painful, disabling or in extreme cases fatal.
Although people with diabetes can develop nerve problems at any time, the risk rises with age, glucose control and how long youve had diabetes. The highest rates of neuropathy are reported among people who have had diabetes for at least 25 years. Diabetic neuropathy seem to be more common in people who have poor glucose control, high cholesterol, high blood pressure or who are overweight.
Yet, you can often prevent diabetic neuropathy or slow its progress with tight blood glucose control and a healthy lifestyle.
What causes diabetic neuropathy?
The causes vary depending upon the type of diabetic neuropathy; though it is well documented that prolonged high glucose levels weakens the walls of the small blood vessels (capillaries) that supply the nerves with oxygen and nutrients. Glucose levels can also damage nerve fibers by interfering with the ability of the nerves to transmit signals.
Nerve damage is generally due to a combination of factors:
Long duration of diabetes, high cholesterol, and possibly low levels of insulin
Autoimmune issues that cause inflammation in nerves
Physical injury to nerves, such as carpal tunnel syndrome
Inherited traits that increase susceptibility to nerve disease
Kidney disease may increase the toxins in the blood and contribute to nerve damage.
Lifestyle factors, such as smoking or alcohol use
Can diabetic neuropathy be prevented?
The best way to prevent neuropathy is to keep your blood glucose levels as close to the normal range as possible. Regular physical activity also keeps the blood flowing to your extremities and keeps tissue oxygenated.
What are the symptoms?
Symptoms depend on the type of neuropathy and which nerves are affected. Symptoms are often minor at first, and because most nerve damage occurs over several years, mild cases may go unnoticed for a long time. However, in some people the onset of pain may be sudden and severe.
Symptoms can involve the sensory, motor, and autonomic nervous systems and may include:
numbness, tingling, or pain in the toes, feet, legs, hands, arms, and fingers
wasting of the muscles of the feet or hands
indigestion, nausea, or vomiting
diarrhea or constipation
dizziness or faintness due to a drop in blood pressure after standing or sitting up
problems with urination
erectile dysfunction in men or vaginal dryness in women
general physical weakness
Symptoms that often accompany neuropathy include weight loss and depression.
There are four main types of diabetic neuropathy. You may have just one type or symptoms of several types. Most develop gradually, and you may not notice problems until considerable damage has occurred.
Each form of neuropathy also comes with its own unique complications which can be life threatening.
Peripheral neuropathy, also called distal symmetric neuropathy or sensorimotor neuropathy, affects the nerves in your toes, feet, legs, hands, and arms. Peripheral neuropathy is the most common form of diabetic neuropathy. Your feet, legs and toes are often affected first, followed by your fingers, hands and arms.
Many people with diabetes feel no symptoms of neuropathy themselves yet still have signs that a doctor can identify in an examination.
Symptoms of peripheral neuropathy may include:
Numbness or insensitivity to pain or changes in temperature
A tingling, burning, or prickling sensation (like the feeling of pins and needles that happens when circulation to your feet is pinched from sitting cross legged)
Sharp pains or cramps
Pain when walking
Extreme sensitivity to touch, even light touch - for some people, even the weight of a sheet can be agonizing
Loss of balance and coordination
Symptoms may be more pronounced at night.
In addition, peripheral neuropathy may also cause muscle weakness and loss of reflexes, especially at the ankle which could lead to changes in the way a person walks and foot deformities.
Blisters and sores may occur on numb areas of the foot because pressure from a poor fitting shoe or injury goes unnoticed. If foot injuries are not treated promptly, the infection may spread to the bone, and the foot may then have to be amputated.
DDFs Executive Director Andrew P. Mandell Mr. Diabetesฎ suffers from severe diabetic neuropathy which causes severe pain and sensitivity in his legs and feet. He also suffers a loss of balance requiring him to walk with a walking stick. In spite of this condition he walked a 10,000+ mile perimeter of the United States. During his walk he had to be vigilant regarding potential injuries. At the end of each day would often pull his shoes off at the end of the day to discover blood on his socks from stepping on a nail, a blister that had formed or his foot and rubbed it raw from a small pebble in his shoe. Good daily foot care is essential for people with peripheral neuropathy.
Autonomic neuropathy affects the nerves that regulate the various organ systems including the heart, digestion, respiratory, urination, sexual response, and vision functions. Autonomic neuropathy can cause changes in digestion, bowel and bladder function, sexual response, and perspiration.
Autonomic neuropathy can also cause hypoglycemia unawareness, a condition in which people no longer experience the warning symptoms of low blood glucose levels.
Nerve damage to the digestive system can cause a variety of problems. Nerve damage to the esophagus may make swallowing difficult. Nerve damage can cause the stomach to empty too slowly, a condition called gastroparesis. Gastroparesis can cause persistent nausea and vomiting, bloating, and loss of appetite. Gastroparesis can also make blood glucose levels fluctuate widely, due to abnormal food digestion. Nerve damage to the bowels can cause constipation alternating with frequent, uncontrolled diarrhea, especially at night. Problems with the digestive system can lead to weight loss.
Urinary Tract and Sex Organs
Autonomic neuropathy can affect the organs that control urination and sexual function in both men and women.
Nerve damage may cause an individual the inability to sense when the bladder is full or control the muscles that release urine. This can result in urinary incontinence or prevent the bladder from emptying completely, allowing bacteria to grow in the bladder and kidneys and causing urinary tract infections.
Autonomic neuropathy can also gradually decrease sexual response in men and women, although libido may be unchanged. A man may suffer from erectile dysfunction or be unable to ejaculate normally. A woman may have difficulty with arousal, lubrication, or orgasm.
Autonomic neuropathy can affect the nerves that control sweating which can create difficulty regulating body temperature. Nerve damage can also cause profuse sweating at night or while eating.
Finally, autonomic neuropathy can affect the pupils of the eyes, making them less responsive to changes in light. As a result, a person may not be able to see well when a light is turned on in a dark room or may have trouble driving at night.
Normally, symptoms such as shakiness, sweating, and palpitations occur when blood glucose levels drop below 70 mg/dL. In people with autonomic neuropathy, symptoms may not occur, making hypoglycemia difficult to recognize.
Proximal neuropathy, sometimes called lumbosacral plexus neuropathy, femoral neuropathy, diabetic amyotrophy, or radiculoplexus neuropathy starts with pain in the thighs, hips, buttocks, or legs, usually on one side of the body.
This condition is often marked by:
Sudden, severe pain in your hip and thigh or buttock
Eventual weak and atrophied thigh muscles
Difficulty rising from a sitting position
Abdominal swelling, if the abdomen is affected
This type of neuropathy is most common among those with type 2 diabetes and in older adults with diabetes. Proximal neuropathy causes weakness in the legs and the inability to go from a sitting to a standing position without help. Treatment for weakness or pain is usually needed. The length of the recovery period varies, depending on the type of nerve damage.
Mono-neuropathy or Focal neuropathy
Mono-neuropathy, which may also be called focal neuropathy, often comes on suddenly. Mono-neuropathy involves damage to a specific nerve. The nerve may be in the face, torso or leg. It's most common in older adults. Although mono-neuropathy can cause severe pain, it usually doesn't cause any long-term problems. Symptoms usually diminish and disappear on their own over a few weeks or months. Signs and symptoms depend on which nerve is involved and may include:
Inability to focus the eye, double vision, aching behind one eye
Paralysis on one side of the face, called Bell's palsy
Severe pain in the lower back or pelvis
Pain in the front of the thigh
Pain in the chest, stomach, or side
Pain on the outside of the shin or inside of the foot
Chest or abdominal pain that is sometimes mistaken for heart disease, a heart attack, or appendicitis
People with diabetes also tend to develop a condition where the nerves compress called entrapment syndromes. One of the most common is carpal tunnel syndrome, which causes numbness and tingling of the hand and sometimes muscle weakness or pain.
Other Complications of Diabetic neuropathy
Even though neuropathy is a complication of diabetes, neuropathy itself can also cause additional complications some of them potentially severe or even life threatening.
Amputation - Nerve damage can cause a lack of feeling in your feet, so its easy for cuts and sores to go unnoticed if you dont do a regular foot exam. Without proper wound care these small cuts or sores can become infected or ulcerated, a condition where the skin and soft tissues break down. The risk of infection is high because diabetes reduces blood flow to your feet.
Infections can spread to the bone and cause tissue death (gangrene). It may be impossible to treat with antibiotics and require amputation of a toe, foot or even the lower leg. More than half the non-traumatic lower limb amputations performed every year in the United States are due to diabetes.
Charcot joint - occurs when a joint, usually in the foot, deteriorates because of nerve damage. Charcot joint is marked by loss of sensation, as well as swelling, instability and sometimes deformity in the joint itself.
Low blood pressure- Damage to the nerves that control circulation can affect your body's ability to adjust blood pressure. This can cause a sharp drop in blood pressure when you stand after sitting (orthostatic hypotension), which may lead to dizziness and fainting.
Social isolation - The pain, disability and embarrassment caused by nerve damage can rob people, particularly older adults, of their independence, leaving them increasingly isolated and depressed.
When to see a doctor
Seek medical care if you notice:
A cut or sore on your foot that doesn't seem to be healing, is infected or is getting worse
Burning, tingling, weakness or pain in your hands or feet that interferes with your daily routine or your sleep
Changes in your digestion, urination or sexual function
How is diabetic neuropathy diagnosed?
Doctors diagnose neuropathy on the basis of symptoms and a physical exam. During the exam, your doctor may check blood pressure, heart rate, muscle strength, reflexes, and sensitivity to position changes, vibration, temperature, or light touch.
Regular foot exams by a doctor
People with diabetes should have a comprehensive foot exam each year to check for peripheral neuropathy. A comprehensive foot exam assesses the skin, muscles, bones, circulation, and sensation of the feet. People diagnosed with peripheral neuropathy need more frequent foot exams.
The doctor may perform other tests as part of your diagnosis.
Nerve conduction studies - This test measures how quickly the nerves in your arms and legs conduct electrical signals. It's often used to diagnose carpal tunnel syndrome.
Electromyography (EMG) - Often performed along with nerve conduction studies, electromyography measures the electrical discharges produced in your muscles.
Quantitative sensory testing - This non-invasive test is used to assess how your nerves respond to vibration and changes in temperature.
Autonomic testing - If you have symptoms of autonomic neuropathy, your doctor may request special tests to look at your blood pressure in different positions and assess your ability to sweat.
If you already have diabetic neuropathy, you'll likely be referred to a podiatrist or other specialist for monitoring and treatment.
How is diabetic neuropathy treated?
Diabetic neuropathy has no known cure. Treatment for diabetic neuropathy focuses on:
Slowing progression of the disease
Managing complications and restoring function
Slowing progression of the disease
Keeping blood glucose levels consistent within a target range can help delay the progression of peripheral neuropathy and may even reduce symptoms you already have. With good glucose control you may reduce your overall risk of diabetic neuropathy by as much as 60%. In addition to blood glucose monitoring, meal planning and physical activity diabetes medicines or insulin will help control blood glucose levels. Discuss appropriate target ranges for your situation with your medical professional.
To help slow nerve damage:
Keep your blood pressure under control
Follow a healthy-eating plan
Get plenty of physical activity
Maintain a healthy weight
Avoid or limit alcohol consumption
Doctors usually treat the pain of diabetic neuropathy with oral medications, although other types of treatments may help some people. People with severe nerve pain may benefit from a combination of medications or treatments. Talk with your health care provider about options for treating your neuropathy.
Over-the-counter pain medicines such as acetaminophen and ibuprofen may not work well for treating most nerve pain and can have serious side effects, so many experts recommend avoiding these medications.
Medications used to help relieve diabetic nerve pain include several classes of anti-depressants. You do not have to be depressed for an antidepressant to help relieve your nerve pain.
Anti-depressants that may be helpful include:
Tricyclic antidepressants, such as amitriptyline, imipramine, and desipramine (Norpramin, Pertofrane)
Other types of antidepressants, such as duloxetine (Cymbalta), venlafaxine, bupropion (Wellbutrin), paroxetine (Paxil), and citalopram (Celexa)
Other drugs including anti-convulsants, such as pregabalin (Lyrica), gabapentin (Gabarone, Neurontin), carbamazepine, and lamotrigine (Lamictal) may be prescribed
Opioids and opioid-like drugs, such as controlled-release oxycodone may be prescribed though long-term use of this class of drugs can cause dependency and should be used as an option of last resort.
Some pain relief treatments are applied to the skin and include capsaicin cream and lidocaine patches. Some studies show nitrate sprays or patches and evening primrose oil may also relieve pain.
Acupuncture, biofeedback, physical therapy or treatments that involve electrical nerve stimulation, magnetic therapy, and laser or light therapy may be helpful.
A device called a bed cradle can keep sheets and blankets from touching sensitive feet and legs.
Managing complications and restoring function
To relieve mild symptoms of indigestion, belching, nausea, or vomiting eating small, frequent meals, avoiding fats and eating less fiber are recommended. With severe symptoms erythromycin may be prescribed to speed digestion, or metoclopramide to speed digestion and help relieve nausea. To relieve diarrhea or other bowel problems, doctors may prescribe an antibiotic such as tetracycline.
Dizziness and Weakness
Sitting, standing or moving slowly may help prevent the light-headedness, dizziness, or fainting associated with blood pressure and circulation problems. Raising the head of the bed or wearing elastic stockings may also help. Some people benefit from increased salt in the diet and treatment with salt-retaining hormones. Others benefit from high blood pressure medications. Physical therapy can help when muscle weakness or loss of coordination is a problem.
Urinary and Sexual Problems
Your doctor will prescribe an antibiotic to treat any urinary tract infections. Drinking plenty of fluids may help prevent another infection. People who have incontinence should try to urinate at regular intervals (every 3 hours) since they may not be able to tell when the bladder is full.
Doctors will do tests to rule out hormonal causes for erectile dysfunction. Medicines are available to help men have and maintain erections by increasing blood flow to the penis. Some are oral medications and others are injected into the penis or inserted into the urethra at the tip of the penis. Mechanical vacuum devices can also increase blood flow to the penis. Another option is to surgically implant an inflatable or semi-rigid device in the penis.
Vaginal lubricants may be useful for women when neuropathy causes vaginal dryness.
People with neuropathy need to take special care of their feet. The nerves to the feet are the longest in the body and are the ones most often affected by neuropathy. Loss of sensation in the feet means that sores or injuries may not be noticed and may become ulcerated or infected. Circulation problems also increase the risk of foot ulcers. More on foot care
Other Methods to reduce your risk of diabetic neuropathy:
Keep your blood pressure under control
Make healthy food choices
- Eat a balanced diet that includes a variety of healthy foods especially fruits, vegetables and whole grains and limit portion sizes to help achieve or maintain a healthy weight.
Be active every day
- In addition to helping you achieve a healthy weight, daily activity protects your heart and improves blood flow to the extremities. It also plays a major role in keeping your blood sugar under control. 30 minutes of moderate exercise a day at least five times a week is key to long-term health. However, if you have severe neuropathy and decreased sensation in your legs, your doctor may recommend that you participate in non-weight-bearing activities, such as bicycling or swimming.
Stop smoking - If you have diabetes and use tobacco in any form, you're more likely to develop circulation problems in your feet.
Updated April 30, 2013