Neuropathy is the collective word for damage to nerves. Neuropathy is one of the most common diabetes related complications, with around 60-70% of people with diabetes having some level of neuropathy.
Peripheral neuropathy (PN) is damage to the nerves in the periphery, in hands and feet. Because the nerves in the feet are furthest from the brain and the spinal cord, the feet are often the first place where patients experience problems. Damage to the peripheral nerves can interfere with the person’s ability to feel pain.
There are 2 types of PN: painless and painful. However, may people experience both types at the same time.
Painless neuropathy is a form of neuropathy where the person describes symptoms such as numbness, feeling like they are walking on cotton wool or a pillow. They will not feel it when their feet are injured and therefore injuries, such as cuts, blisters, cracks in callus, can go undetected and develop into significant health issues such as ulceration, osteomyelitis and gangrene.
Painful neuropathy is a form of neuropathy where the person becomes over-sensitised to pain. They often describe symptoms such as burning, stabbing or shooting pains, pins and needles, and cramps. It is not uncommon for people to feel extreme pain from things that normally don’t cause pain, such from socks or bed sheets lying across the feet at night.
PN may also cause a loss of balance, coordination and increase trips and falls. This can affect the person’s mobility, confidence and independence.
Diabetic Autonomic Neuropathy (DAN) is another form of neuropathy that can affect people with diabetes. DAN is mostly present together with other diabetes complications, such as peripheral neuropathy. It makes sense, that if the nerves in the legs are affected the nerves around the abdomen would similarly be affected. DAN may occur on its own, or may be diagnosed before other diabetes related complications are established. More on this in a future edition of this newsletter.
Risk factors for PN
Risk factors for developing PN include: hyperglycaemia, hypertension, vitamin B deficiency, alcohol, smoking, kidney or liver disease and some drugs used in cancer treatments.
The longer the person has diabetes, the more likely they are to develop PN.
How is it diagnosed?
A diagnosis of neuropathy is made through a detailed history of symptoms and a physical examination, which will include testing the level of feeling with simple instruments, such as a monofilament, tendon hammer or biothesiometer. Neurologist can organise nerve conduction tests if the diagnosis remains unclear.
Treating peripheral neuropathy
Underlying conditions, such as hyperglycaemia, hypertension and vitamin B deficiency, will need to be addressed first and foremost. Alcohol and smoking are also risk factors for the development of PN and hence the patient should be supported to stop smoking and decrease their alcohol intake.
Regular analgesia usually don’t work, but neuropathic pain agents may help. Opioids, such as tramadol or oxycodone, can lead to dependence and addiction and hence these medications are generally only prescribed when other treatments fail.
Medications such as gabapentin and pregabalin, developed to treat epilepsy, may relieve nerve pain; side effects can include drowsiness and dizziness.
Capsaicin cream, which contains a substance found in hot peppers, can provide some improvements in PN symptoms, particularly for burning pain, but not all patients can tolerate the skin burning and irritation that can come with this treatment.
Certain tricyclic antidepressants, such as amitriptyline, doxepin and nortriptyline, have been found to help relieve pain by interfering with chemical processes in the brain and spinal cord that cause the person to feel pain.
The serotonin and norepinephrine reuptake inhibitor duloxetine and the extended-release antidepressant venlafaxine also might ease the pain of peripheral neuropathy caused by diabetes.
Prevention of PN
Regular visits to a podiatrist can help diagnose PN in earlier stages and this may help in slowing the development of symptoms and can help in preventing further complications.
Patients can obtain an EPC referral from their GP to access up to 5 Medicare rebate visits per year to allied health professionals, including podiatrists, to help with any costs involved.
If you like to provide more information on neuropathy to your patients you may find these resources useful:
Find out about Nevro HF10TM Spinal Cord Stimulation, innovation in the treatment of Painful Diabetic Neuropathy for those patients who are not able to be managed through conventional medical management.