What is Diabetic Neuropathy?
Diabetic neuropathy is nerve injury due to diabetes. Other causes of nerve injury such as vitamin B12 deficiency, trauma, alcoholism, infectious disease, malignancies, thyroid disease, kidney and liver disease, autoimmune disease, must be excluded.
Patients with type 1 diabetes for at least 5 years and all type 2 diabetes patients should be evaluated yearly for the presence of diabetic peripheral neuropathy.
What are the Common Signs & Symptoms of Diabetic Neuropathy?
- Decreased or loss of sensation to pinprick, temperature, vibration, and monofilament.
- Numbness, tingling, burning, pain, increased sensitivity to touch at hands and feet. Feet are affected more than hands.
- Decreased or loss of deep tendon reflexes.
- Weakness involving hands and feet. This can present as difficulty opening a jar or frequent tripping or toe scuffing.
- Cardiovascular: orthostatic hypotension (a drop in blood pressure upon standing) and fast heart rate above 100 beats per minute at rest.
- Gastrointestinal: gastroparesis or slow stomach emptying can occur when there is damage to the nerve that affects stomach muscles. In addition, other symptoms of gastrointestinal involvement include abdominal pain, nausea, vomiting, constipation, diarrhea and stool incontinence.
- Genitourinary: erectile dysfunction, problems with bladder control and poor urinary stream.
What are the Risk Factors for Developing Severe Diabetic Neuropathy?
- Poor glucose control
- Advanced age
- Hypertension or elevated blood pressure
- Long duration of diabetes
- Elevated cholesterol levels
- Heavy alcohol consumption
How is Diabetic Neuropathy Diagnosed?
- Laboratory tests to exclude other causes.
- Physical exam
- Electromyogram (EMG) of muscles affected and nerve conduction testing with referral to neurologist is rarely needed.
Why is it Important to Diagnose Diabetic Neuropathy?
- It is important to check for neuropathy in diabetics because poor or absent sensation in the feet can lead to foot ulcers and amputation. Also, patients can be at increased risk for fall when they lose the protective sensation at the feet.
How do I Treat Diabetic Neuropathy?
- Good glucose control can prevent diabetic neuropathy in type 1 diabetics, and it can slow progression of disease in type 2 diabetics.
- Pain management:
Antidepressants (Duloxetine or Cymbalta, Amitriptyline or Elavil)
Anticonvulsants (Gabapentin or Neurontin, Pregabalin or Lyrica)
- Topicals (Capsaicin, Lidocaine)
- Physical therapy for muscle pain and weakness.
- Treatment of orthostatic hypotension includes both non-medication (adequate fluid intake, avoid aggravating medications, compression stockings) and medication such as Midodrine.
- Treatment of gastroparesis includes eating frequent small meals and avoiding drugs that decrease gastric motility such as opioids. Metoclopramide is a drug that can help increase gastric motility, but it has neurologic risk that prevents its use for longer than 12 weeks. An implanted electrical device to stimulate stomach motility has been approved for use for patients with severe gastroparesis unresponsive to other treatments.
Quan, D., 2020, Diabetic Neuropathy, Medscape, Jan. 17, 2020.
Khardori, R., 2020,Type 2 Diabetes Mellitus Overview, Medscape, May 28, 2020.
Diabetes Care, January 2019, Volume 42, Supplement 1.