New Guidelines for the Treatment of Painful Diabetic Neuropathy

The AAN and other medical societies recently released comprehensive guidelines for the pharmacologic and nonpharmacologic treatment of diabetic neuropathy.

The American Academy of Neurology (AAN) recently issued a new guideline on effective treatment for painful diabetic neuropathy, developed in collaboration with the American Association of Neuromuscular and Electrodiagnostic Medicine and the American Academy of Physical Medicine and Rehabilitation.

The introduction to the full text of the guidelines, which are available for download as a PDF, notes that the document “addresses the efficacy of pharmacologic and nonpharmacologic treatments to reduce pain and improve physical function and [quality of life] in patients with [painful diabetic neuropathy].” Pharmacologic agents evaluated in the guidelines include anticonvulsants, antidepressants, opioids, anti-arrhythmics, cannabinoids, aldose reductase inhibitors, protein kinase C beta inhibitors, antioxidants, transketolase activators, and topical medications. Nonpharmacologic treatment modalities evaluated in the course of guideline creation included “infrared therapy, shoe magnets, exercise, acupuncture, external stimulation (transcutaneous electrical nerve stimulation), spinal cord stimulation, biofeedback and behavioral therapy, surgical decompression, and intrathecal baclofen.”

A summary of the guidelines for clinicians notes that there is “strong evidence” (level A) supporting the clinically appropriate use of pregabalin to treat painful diabetic neuropathy. For other anticonvulsants and antidepressants, the guidelines also found:

• Moderate (level B) evidence for the use of gabapentin and sodium valproate for the treatment of PDN
• Moderate (level B) evidence suggesting that oxcarbazepine, lamotrigine, and lacosamide should not be considered for the treatment of PDN.
• There is insufficient (level U) evidence “to support or refute the use of topiramate for the treatment of PDN.”
• Moderate (level B) evidence supporting the use of amitriptyline, venlafaxine, and duloxetine for treating PDN. There is insufficient evidence to suggest that one of these agents is superior to another.
• Weak (level C) evidence to support adding venlafaxine to gabapentin treatment.
• Insufficient (level U) evidence “to support or refute the use of desipramine, imipramine, fluoxetine, or the combination of nortriptyline and fluphenazine in the treatment of PDN.”

The evidence for the use of opioids and other pharmacologic agents for the treatment of PDN was also mixed, with only moderate evidence supporting the use of dextromethorphan, morphine sulphate, tramadol, and oxycodone (with insufficient evidence to support favoring one medication over another), and only moderate evidence supporting the use of capsaicin and isosorbide dinitrate spray. The summary notes that although capsaicin “has been effective in reducing pain in PDN clinical trials, many patients are intolerant of the side effects, mainly burning pain on contact with warm/hot water or in hot weather.”

The guideline authors found only moderate evidence supporting the use of percutaneous electrical nerve stimulation for the treatment of PDN, and recommend that “electromagnetic field treatment, low-intensity laser treatment, and Reiki therapy should probably not be considered for the treatment of PDN.”

In a news release from the AAN, lead guideline author Vera Bril, MD, FRCP, University of Toronto, said that she and her fellow authors “were pleased to see that so many of these pain treatments had high-quality studies that support their use,” but cautioned that “it is important that more research be done to show how well these treatments can be tolerated over time since diabetic nerve pain is a chronic condition that affects a person’s quality of life and ability to function.”

The AAN release also noted that the recommendations in the guideline will “serve as the foundation for a new set of tools the AAN is creating for doctors to measure the quality of care they provide people with nerve pain.” The new tools and measures are expected to be ready in 2012.