Comparing Treatments for Painful Diabetic Neuropathy

DPN pain is difficult to treat, and not all patients respond to treatment. Optimization of glycemic control is widely accepted as the first step in managing DPN pain (although the related evidence is unclear and even contradictory), followed by pharmacological approaches. During his presentation, Dr Cuevas-Trisan noted that components of metabolic syndrome may also “be potential risk factors since these CV risk factors cluster with hyperglycemia.” For example, higher rates of neuropathy, higher pain scores, and lower quality of life have been observed in individuals with vs individduals without obesity, even in the absence of prediabetes or diabetes.⁴

Pharmacologically, DPN pain is most often managed with adjuvants such as anticonvulsants and various classes of antidepressants. “Treatment recommendations have evolved over the last 10 years, based on newer agents and more medical evidence showing efficacy of some agents and lack of efficacy of others,” noted Dr Cuevas-Trisan. The agents most supported by existing data are tricyclic antidepressants, pregabalin, duloxetine, and venlafaxine. While opioids should generally be avoided, tapentadol or tramadol may be considered in certain cases.

Dr Cuevas-Trisan reviewed this evidence in his presentation, along with the International Association for the Study of Pain (IASP) algorithm for neuropathic pain treatment, and the guidelines for managing painful diabetic neuropathy that were jointly published in 2011 by the American Academy of Neurology, the American Association of Neuromuscular and Electrodiagnostic Medicine, and the American Academy of Physical Medicine and Rehabilitation.^5,6  These guidelines showed level A evidence for the effectiveness of pregabalin, and level B evidence for treatments such as gabapentin, sodium valproate, morphine, dextromethorphan, capsaicin, and electrical stimulation. Therapies such as oxcarbazepine, lamotrigine, clonidine, and laser therapy were not recommended. However, in a 2017 systematic review of evidence published since the 2011 guidelines were released, the guideline authors concluded that gabapentin, opioids, dextromethorphan, and capsaicin are not effective, but that oxcarbazepine was shown to be effective.⁷

In addition, the importance of exercise in reducing disability and preserving function were  discussed, as well as emerging treatments for DPN pain, including botulinum toxins, α-lipoic acid, and cannabinoids. “Agent selection depends on various factors including other medical conditions, cost, and experience of the provider managing these,” said Dr Cuevas-Trisan.