Polyneuropathy occurs when multiple peripheral nerves malfunction throughout the body. Neuropathy is a common complication of type 2 diabetes mellitus (T2DM).

T2DM is a condition that occurs when the body develops insulin resistance and no longer responds effectively to insulin. This can make blood sugar levels difficult to manage and can result in high blood sugar, or hyperglycemia. Without proper management of this condition, people may experience complications such as neuropathy, or nerve damage.

Polyneuropathy occurs when there is damage to multiple nerves in the peripheral nervous system in different parts of the body at the same time. Peripheral nerves are the nerves outside the brain and spinal cord. If a person does not receive treatment, diabetic polyneuropathy can lead to infections, ulcers, and other complications.

Read on to learn more about the relationship between T2DM and diabetic polyneuropathy.

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“Neuropathy” is another term for nerve damage. When neuropathy affects only one nerve, healthcare professionals call it mononeuropathy. However, when it involves damage to many nerves, they refer to it as polyneuropathy. There are four main types of neuropathy: peripheral, autonomic, proximal, and focal.

Peripheral neuropathy

Peripheral neuropathy affects the peripheral nervous system, which connects the brain and spinal cord to distant parts of the body. This system controls motor and sensory functions throughout the body.

People with peripheral neuropathy may experience symptoms such as muscle weakness, loss of feeling in the hands and feet, pain, and sensitivity to heat.

Autonomic neuropathy

Autonomic neuropathy involves damage to nerves within the internal organs. This condition can affect blood pressure, bladder control, digestion, and more.

The symptoms of autonomic neuropathy depend on which internal organs it affects. The condition can cause digestive symptoms ranging from constipation and nausea to vomiting and incontinence. It can also damage nerves in the eye, making it difficult for the eye to respond to light changes.

Proximal neuropathy

Proximal neuropathy is a rare condition that involves nerve damage in the thighs, hips, or buttocks. Most people with this condition experience nerve damage on only one side of the body. Proximal neuropathy is most common in people over age 50.

People with this condition may have symptoms such as muscle wasting, weakness in the legs, pain, or weight loss. They may also lose certain reflexes.

Focal neuropathy

Focal neuropathy affects single nerves. Most often, this type of nerve damage affects nerves in the hand, head, leg, or torso. Symptoms will depend on the affected nerves. Common symptoms include pain, numbness, and tingling.

People living with T2DM may experience high blood sugar, which can lead to nerve damage and can damage blood vessels that deliver oxygen to the nerves. When they do not receive enough oxygen, these nerves also become damaged.

Certain health factors can increase the chance of diabetic polyneuropathy in people with T2DM. These include:

  • high body mass index
  • longer duration of diabetes
  • history of smoking
  • female sex

It is advisable for people with T2DM to consult a doctor about their risk of polyneuropathy. A medical professional can recommend preventive steps and provide guidance on how to manage polyneuropathy symptoms.

The symptoms of polyneuropathy may vary from person to person and will depend on the nerves the condition affects. However, common symptoms include:

  • pain in the limbs
  • increased sensitivity
  • numbness and tingling
  • sleep disturbances
  • inability to feel pain or temperature changes
  • coordination issues
  • lack of feeling around cuts or sores
  • balance issues
  • low blood pressure
  • foot and leg ulcers
  • skin and nail infections

Anyone experiencing polyneuropathy symptoms should contact a medical professional, who can perform a full evaluation and deliver a diagnosis.

People with T2DM should consult a doctor if they experience polyneuropathy symptoms. During this visit, a doctor will perform a range of tests to check nerve function, including:

  • sensory testing
  • nerve conduction tests
  • skin biopsy
  • corneal confocal microscopy

A doctor may also use a questionnaire or scale to score a person’s symptoms. A high symptom score may indicate polyneuropathy. If necessary, a healthcare professional can refer a person to a specialist for further testing and a formal diagnosis.

Treating diabetic neuropathy is an individualized process. A person may find that certain treatments work better for their unique case. Treatment options for diabetic polyneuropathy may include:

  • certain antidepressants
  • analgesics
  • topical pain relievers
  • acupuncture
  • physical therapy
  • electrical nerve stimulation

Research has also shown that dietary changes and exercise can help relieve polyneuropathy symptoms. These lifestyle interventions help regulate blood sugar and reduce discomfort. To learn more about treatment options, speak with a doctor.

Without proper treatment, diabetic polyneuropathy can lead to serious complications such as:

  • pain
  • foot infections and ulcers
  • falls due to dizziness
  • dehydration and diarrhea
  • heart damage
  • foot, leg, or toe amputations

To avoid complications, it is important to share new or worsening symptoms with a doctor. Prompt and effective treatment can reduce the risk of serious health complications.

Polyneuropathy involves damage to many nerves throughout the body at the same time. People with T2DM have a higher risk of developing polyneuropathy because high blood sugar can lead to significant nerve damage over time.

Symptoms of polyneuropathy can vary depending on the type of nerve the condition affects. Certain medications and lifestyle changes can help a person manage polyneuropathy symptoms. To learn more about individualized treatment options, a person can speak with a healthcare professional.