To the Editor:

We appreciate the comprehensive review of diabetic peripheral neuropathy by Drs. Bragg, Marrison, and Haley and agree on the significance of a preference-sensitive, multimodal treatment plan.¹ The authors allude to nondrug therapies (eg, neuromodulation, exercise), but cognitive behavior therapy (CBT) and mindfulness may also be effective modalities for some patients with diabetic peripheral neuropathy. A systematic review found evidence supporting CBT and mindfulness therapy in the treatment of diabetic peripheral neuropathy, demonstrating improvement in pain severity, pain interference, quality of life, and depressive symptoms; the treatment effect size was small, but it is comparable to neuromodulatory treatments.² Although large, rigorous studies of CBT and mindfulness in patients with diabetic peripheral neuropathy have yet to be completed, CBT has shown promise in other chronic pain conditions that may share overlapping mechanisms with diabetic peripheral neuropathy, including fibromyalgia, headache, and low back pain.

Given the low risk of adverse events, primary care physicians should consider CBT for patients with diabetic peripheral neuropathy before more invasive, high-risk interventions with weak supporting evidence, such as spinal cord stimulators.³ Further, studies of transcutaneous electrical nerve stimulation for diabetic peripheral neuropathy are limited by small sample size, limited follow-up, and short treatment duration.⁴

Although many patients benefit from first- and second-line oral or topical pharmacologic agents for diabetic peripheral neuropathy, some patients will experience intolerable adverse effects, have contraindications to oral pharmacotherapy, or find topical agents difficult to incorporate into their lifestyle. For these patients, CBT and mindfulness therapies are valuable alternatives to consider. Self-guided CBT has been evaluated for other pain conditions and may present a low-entry, low-cost, and acceptable alternative for patients in cases where accessing CBT is challenging.⁵

In Reply:

We concur that nondrug therapies play a valuable role in the treatment of patients with diabetic peripheral neuropathy. Several therapies hold promise to improve pain and quality of life with notably limited risks from treatment.^1,2 Multimodal approaches such as CBT and mindfulness rely on the complex relationship between chronic disease, comorbid depression, and pain.³ Although CBT and mindfulness have been evaluated in small pilot studies for patients with painful diabetic peripheral neuropathy, the findings have varied, with some studies showing no benefit and others demonstrating moderate improvements in pain and quality of life. As would be expected, these interventions have shown significant improvements in depressive symptoms for patients.² Rigorous randomized controlled trials of CBT and mindfulness for treatment of patients with painful diabetic peripheral neuropathy are needed to increase confidence of their benefits; however, the risks of these interventions are low, so they should be considered as adjunctive options for patients with refractory pain.

Similarly, exercise-based interventions for patients with painful diabetic peripheral neuropathy have shown mixed results.⁴ One study including 39 patients showed that tai chi reduced pain scores significantly and improved quality of life.⁵ It has been suggested that physical activity and psychological treatments such as CBT target coping strategies as opposed to only the pain itself, which may explain the reason that these therapies contribute to quality-of-life improvements.⁴ Many of the studies on exercise are limited by sample size and the quality of study, but they pose few harms.

When approaching patients with painful diabetic peripheral neuropathy, it is imperative to use a biopsychosocial approach to treatment, incorporating multimodal therapy. Patients with comorbid depression and anxiety may gain more from CBT and mindfulness interventions, whereas others with intolerances to drugs may prefer physical activity and neuromodulatory-based techniques.^1,2,6 Therapy decisions must incorporate social determinants of health, including access to and cost of care, to optimize a comprehensive treatment plan.