There are four main types of diabetic neuropathy (peripheral, autonomic, radiculoplexus neuropathy, and mononeuropathy), but the most common type is peripheral neuropathy, which usually affects the feet and the legs but sometimes the hands and the arms are also involved. Almost one-third to one-half of people with diabetes develop peripheral neuropathy.
Diabetic neuropathy can be prevented, or its progress slowed by maintaining tight blood sugar control and a healthy lifestyle.
What causes diabetic neuropathy?
Over time, if diabetes is left untreated or is not well treated, high blood sugar (glucose) levels as well as high levels of fats, such as triglycerides, can damage the nerves throughout the body. This can lead to diabetic neuropathy.
What are the symptoms of diabetic neuropathy?
Symptoms of diabetic neuropathy develop slowly and you may not notice that anything is wrong until considerable damage has been done.
Symptoms vary depending on which of the four main types of diabetic neuropathy you have (although people can have more than one type).
Symptoms are usually worse at night and may include:
- A reduced ability to feel pain or temperature changes
- A loss of reflexes, particularly in the ankles
- A tingling or burning sensation
- Bone and joint pain
- Increased sensitivity to touch
- Loss of balance and coordination
- Muscle weakness
- Numbness in the legs and feet initially, sometimes followed by the hands and arms
- Sharp pains and leg cramps
- Ulcers or wounds that are slow to heal on the feet and legs
The autonomic nervous system acts largely involuntarily and controls the heart, bladder, stomach, intestines, sex organs and eyes. Diabetic neuropathy that affects the nerves in any of these areas is called autonomic neuropathy. Symptoms may include:
- A loss of the warning signs of low blood sugar levels (such as shakiness, dizziness, hunger); this is called "Hypoglycemia unawareness"
- Bladder and urinary problems, including urinary incontinence, retention, and an increased risk of infections
- Bowel problems, such as constipation or diarrhea or both
- Difficulty swallowing
- Difficulty controlling body temperature
- Erectile dysfunction
- Increased or decreased sweating
- Increased heart rate at rest
- Slow stomach emptying (this is called gastroparesis), nausea, vomiting, bloating and loss of appetite
- Problems controlling body temperature
- Postural hypotension (a sharp drop in blood pressure when going from a sitting to standing position)
- Vaginal dryness
This type of neuropathy affects the nerves in the thighs, hips, buttocks or legs, and more commonly affects people with type 2 diabetes and older adults. Radiculoplexus neuropathy may also be called diabetic amyotrophy, femoral neuropathy or proximal neuropathy.
Symptoms usually affect one side of the body, but may spread to the other side, and may include:
- Severe hip, thigh, or buttock pain
- Weak and shrinking thigh muscles
- Difficulty rising from a sitting position
- Weight loss
- Abdominal swelling
Mononeuropathy is damage to a specific nerve in the face, middle of the body (torso), or leg and mostly affects older adults. It often strikes suddenly and can cause severe pain, although usually doesn't cause any long-term problems and goes away without treatment over a few weeks or months. Mononeuropathy may also be called focal neuropathy.
Symptoms include pain in one of the following areas:
- Chest or abdomen
- Face, causing symptoms such as difficulty focusing, double vision, aching behind one eye, paralysis on one side of the face (Bell's palsy)
- Front of thigh
- Hand or fingers (eg, Carpal tunnel syndrome)
- Lower back or pelvis
- Shin or foot
How is diabetic neuropathy treated?
There is no cure for diabetic neuropathy and treatment aims to relieve pain, slow disease progression, manage complications, and restore function.
Treatment may include:
- Insulin or oral hypoglycemics to maintain tight blood sugar control
- Medications for pain relief (which may include capsaicin, anticonvulsants, or antidepressants)
- Other medications may be used off-label.