Diabetic Neuropathy

What is Diabetic Neuropathy?

Diabetic neuropathy is a common, yet serious, and disabling complication of diabetes. It can be painful and/or cause numbness due to the nerve damage thatoccurs from high blood sugar (glucose) injuring nerves throughout your body. The most commonly damaged nerves are in the legs and feet; However, it can cause damage in your digestive system, urinary tract, blood vessels and heart.

Tight blood sugar control and a healthy lifestyle can often prevent diabetic neuropathy or slow its progress.

Diabetic Peripheral Neuropathy

What Are The Symptoms?

There are four main types of diabetic neuropathy, of which you can have one or more types. The type(s) of neuropathy and the nerves affected will determine your symptoms. Typically initial symptoms are mild and slowly worsen over time, so you may not notice anything is wrong until significant nerve damage has occurred.

Peripheral Neuropathy

This is the most common type of diabetic neuropathy. The feet and legs are affected first, followed by the hands and arms. Signs and symptoms of peripheral neuropathy are often worse at night, and may include:

  • Numbness or reduced ability to feel pain or temperature changes

  • Tingling or burning sensation

  • Sharp pains or cramps

  • Increased sensitivity to touch

  • Muscle weakness

  • Loss of reflexes, balance and coordination

  • Serious foot problems (ulcers), infections, and bone and joint pain

Autonomic Neuropathy

Your heart, bladder, stomach, intestines, sex organs and eyes are controlled by the autonomic nervous system. Diabetes can affect nerves in any of these areas, possibly causing:

  • A lack of awareness that blood sugar levels are low

  • Bladder problems

  • Constipation, uncontrolled diarrhea or both

  • Slow stomach emptying (gastroparesis), causing nausea, vomiting, bloating and loss of appetite

  • Difficulty swallowing

  • Increased or decreased sweating

  • Problems controlling body temperature

  • Changes in the way your eyes adjust from light to dark

  • Increased heart rate at rest

  • Sharp drops in blood pressure after sitting or standing that may cause you to faint or feel lightheaded

  • Decreased sexual response, erectile dysfunction, and vaginal dryness

Radiculoplexus Neuropathy (Diabetic Amyotrophy)

Radiculoplexus neuropathy affects nerves in the thighs, hips, buttocks or legs, and is more common in people with type 2 diabetes and older adults. This type is also known as diabetic amyotrophy, femoral neuropathy or proximal neuropathy. Symptoms are usually on one side of the body, but sometimes may spread to the other side. You may have:

  • Severe pain in a hip and thigh or buttock that occurs in a day or more

  • Weak and shrinking thigh muscles

  • Difficulty rising from a sitting position

  • Abdominal swelling

  • Weight loss

Most people improve at least partially over time, though symptoms may worsen before they get better.

Mononeuropathy

Mononeuropathy, or focal neuropathy, is damage to a specific nerve in the face, middle of the body (torso) or leg. It’s most common in older adults. Mononeuropathy often strikes suddenly and can cause severe pain. Symptoms usually go away without treatment over a few weeks or months. Your specific signs and symptoms depend on which nerve is involved. You may have pain in the:

  • Shin or foot

  • Lower back or pelvis

  • Front of thigh

  • Chest or abdomen

Nerve problems in the eyes and face may lead to difficulty focusing, double vision, aching behind one eye, and paralysis on one side of your face (Bell’s palsy)

Mononeuropathy can also occur when a nerve is being compressed. Carpal tunnel syndrome is a common type of compression neuropathy in people with diabetes. This can cause numbness or tingling in your hand or fingers, except your pinkie (little finger). Your hand may feel weak, and you may drop things.

What Are The Causes?

The current theory of how diabetic neuropathy occurs is that over time, uncontrolled high blood sugar damages nerves and their ability to send signals. The walls of small blood vessels (capillaries) that supply your nerves with oxygen and nutrients are also weakened. However, a combination of factors may lead to nerve damage, including:

  • Inflammation

  • Genetic factors

  • Smoking and alcohol abuse

Risk Factors

Anyone who has diabetes can develop neuropathy, but these risk factors make you more likely to get nerve damage:

  • Poor blood sugar control

  • How long you’ve had diabetes (the longer you’ve had diabetes, the higher the risk)

  • Kidney disease

  • Being overweight

  • Smoking

Diagnosis

Your primary care doctor can usually diagnose diabetic neuropathy by performing a physical exam and carefully reviewing your symptoms and medical history. Your pain doctor will also check your overall muscle strength and tone, tendon reflexes and sensitivity to touch and vibration. In addition, the American Diabetes Association recommends that all people with diabetes have a comprehensive foot exam at least once a year.

Your doctor may also order specific tests to help diagnose diabetic neuropathy, such as:

  • Quantitative sensory testing

  • Nerve conduction studies

  • Electromyography (EMG)

  • Autonomic testing

What Are The Treatments?

Diabetic neuropathy has no known cure. The goals of treatment are to slow progression of the disease, relieve pain, and manage complications and restore function

Slowing Progression of the Disease

  • Consistently keeping your blood sugar within your target range

  • Blood pressure control

  • Maintaining a healthy weight and lifestyle

Relieving Pain

Medications available for diabetes-related nerve pain include:

  • Anti-seizure drugs. These medications were developed to treat seizures, but have been shown to be very effective for nerve pain. These commonly used medications include pregabalin (Lyrica), gabapentin (Gralise, Neurontin) and carbamazepine (Carbatrol, Tegretol). Side effects may include drowsiness, dizziness and swelling.

  • Antidepressants. The same chemicals in your brain that are associated with depression can help decrease nerve pain even if you do not have depression. The two classes of antidepressants used include:

    • Tricyclics (TCAs), including amitriptyline, desipramine (Norpramin) and imipramine (Tofranil), may provide relief for mild to moderate symptoms. But side effects can be bothersome and include dry mouth, sweating, weight gain, constipation and dizziness.

    • Serotonin and norepinephrine reuptake inhibitors (SNRIs) include duloxetine (Cymbalta) and venlafaxine (Effexor XR). These are typically better tolerated than TCAs and usually have fewer side effects, but can cause nausea, sleepiness, dizziness, decreased appetite and constipation.

Sometimes, an antidepressant may be combined with an anti-seizure drug or pain-relieving medication.

Interventional procedures for diabetic neuropathy include:

  • Spinal cord stimulation. This can help decrease pain, and some studies have shown improvement in other symptoms such as numbness/tingling and overall function.

Managing Complications and Restoring Function

Treatments depend on the neuropathy-related complication(s) you have and should be discussed with your doctor.

You can prevent or delay diabetic neuropathy and its complications by keeping tight control of your blood sugar and taking good care of your feet.

  • Monitor your blood sugar at home

  • A1C  test at least twice a year

  • Comprehensive foot exam at least once a year

  • Take good care of your feet at home (Check your feet every day; Keep your feet clean and dry; Trim your toenails; Wear clean dry socks and cushioned well fitting shoes)

If you qualify for Medicare, your plan may cover the cost of at least one pair of shoes each year