High-Frequency Spinal Cord Stimulation Could Offer Hope in Refractory Diabetic Neuropathy

Erika Petersen, MD

Results from a recent trial indicate a new option may be available in the future to provide pain relief in patients with peripheral diabetic neuropathy struggling to find a safe and efficacious treatment.

A randomized clinical trial of more than 200 patients with refractory peripheral diabetic neuropathy, results of the trial indicate 10-kHz spinal cord stimulation was associated with substantial pain relief and improve quality of life.

“Patients with peripheral diabetic neuropathy refractory to best available treatments can be safely and effectively treated with high-frequency (10-kHz) spinal cord stimulation. Evidence-based treatment guidelines should contemplate positioning of 10-kHz spinal cord stimulation in the continuum of care. Follow-up of this study population will continue for 24 months and establish potential durability of this treatment beyond 6 months,” wrote study investigators.

Despite advances in diabetes care, research indicates a high percentage of patients with peripheral diabetic neuropathy struggle to address pain caused by their condition. With this in mind, clinicians and patients have sought nonpharmacological treatment options, including use of spinal cord stimulation devices. While investigators dated use back to 1996, few randomized clinical trials have examined use of spinal cord stimulation for the management of chronic pain in these patients.

With this in mind, a team led by Erika Petersen, MD, of the Department of Neurosurgery at the University of Arkansas, designed the largest randomized clinical trial of spinal cord stimulation in peripheral diabetic neuropathy. Named SENZA-PDN, the trial was designed as a prospective, multicenter, open-label trial comparing conventional medical management to 10-kHz spinal cord stimulation plus conventional medical management in patients from 18 medical centers in the US.

For inclusion in the trial, patients needed to have peripheral diabetic retinopathy for 1 year or more refractory to gabapentinoids and at least 1 other analgesic class, lower limb pain intensity of 5 cm or more on a 10-cm visual analogue scale (VAS), a BMI of 45 or less, an HbA1c of 10% or less, daily morphine equivalents of 120 mg or less, and be deemed medically appropriate for the procedure.

The trial’s primary endpoint was the percentage of patients with 50% pain relief or more on VAS without deterioration of neurological deficits at 3 months. The trial’s secondary endpoints included change in pain VAS, neurological examinations, health-related quality of life, and HbA1c over 6 months.

In total, 430 patients underwent screening and 216 were randomized—of these, 187 patients were evaluated at the 6-month follow-up. The cohort that underwent randomization was 63% male and had a mean age of 60.8 (SD, 10.7) years. The median duration of diabetes and diabetic peripheral neuropathy was 10.9 (6.3-16.4) years and 5.6 (3.0-10.1) years, respectively.

Upon analysis, results indicated the primary endpoint was achieved by just 5 of the 94 patients in the conventional medical management arm compared to 75 of 95 patients in the spinal cord stimulation arm (difference, 73.6%; 95% CI, 64.2-83.0; P <.001). Investigators noted infections requiring device plant occurred in 2 patients within the spinal cord stimulation arm of the trial.

When assessing secondary outcomes, investigators found the mean pain VAS score for the conventional medical management arm was 7.0 cm (95% CI, 6.7-7.3 and 6.9 cm (95% CI, 6.5-7.3) at baseline and 6 months, respectively. For the spinal cord stimulation arm, mean pain VAS score was 7.6 cm (95% CI, 7.3-7.9) at baseline and 1.7 cm (95% CI, 1.3-2.1) at 6 months. When assessing data from neurological examinations investigators noted improvements among 3% of those in the conventional management arm and 62% of those in the spinal cord stimulation arm at 6 months (difference, 58.6%; 95% CI, 47.6-69.6; P <.001).

"The substantial pain relief and improved quality of life sustained over six months demonstrates that this therapy can safely and effectively treat this patient population. I'm grateful to my co-investigators and the patients who participated in this study, as the results will have far-reaching impact on the lives of PDN patients,” said Petersen, in a statement from Nevro Corp.

This study, “Effect of High-frequency (10-kHz) Spinal Cord Stimulation in Patients With Painful Diabetic Neuropathy,” was published in JAMA Neurology.