A Randomized, Sham-Controlled, Double-Blind Pilot Study of Pulsed Electromagnetic Field Therapy to Evaluate Small Fiber Nerve Growth and Function and Skin Perfusion in Subjects with Painful Peripheral Diabetic Neuropathy

Abstract

Abstract:Purpose: The objective of this study was to determine the potential efficacy and safety of dual energy pulsed electromagnetic field therapy (PEMF) on painful distal symmetric diabetic sensorimotor polyneuropathy (DSPN).Methodology: Subjects with Type 2 diabetes and painful DSPN were randomized to receive either an active or sham PEMF device. Objective measures of efficacy (skin biopsy, nerve conduction velocity (NCV) studies, dorsal and plantar foot skin perfusion pressure (SPP) were performed prior to and following 60-days of twice daily 30 minute treatments. Patient reported outcomes included perception of pain, concomitant medication use and adverse events.Major findings: Dorsal foot SPP improved with PEMF (n=11), change from baseline=19.6 mmHg) vs. sham (n=7, change=-17.4 mmHg), p=0.03. Trends in favor of PEMF vs sham were observed for medial nerve (n=4), planter nerve (n=4) and sural nerve (n=15) onset time and amplitude (p>0.05) other than medial planter onset time (p=0.04). Although change in pain scores were similar, compliance with device use was higher in the active group compared to the sham control. The series of tests and long-term use of PEMF was well-tolerated and feasible. No device related adverse effects were recorded.Principal conclusions: Twice daily PEMF therapy was feasible, well-tolerated, and associated with trends suggesting improved nerve function and microcirculation in patients with painful DSPN. Future, large randomized controlled trials are necessary to confirm these findings and evaluate the potential longer term benefits on symptoms and pathology of DSPN.Keywords: Diabetes; Nerve conduction velocity; Peripheral neuropathy; Pulsed electromagnetic field; Skin biopsy; Skin perfusion pressure Key MessagesPainful diabetic neuropathy affects the majority of patients with diabetes during their lifetime. The presence of diabetic neuropathy increases the potential for diabetes-related lower extremity complications.The aim of this randomized, sham-controlled trial was to determine the feasibility and effects of 60 days of treatment with PEMF therapy on skin perfusion, nerve growth and function as well as pain perception, compliance and safety in subjects with painful diabetic neuropathy. Nineteen patients (12 active; 7 sham) participated in this study.This pilot study demonstrated feasibility of use and trends in favor of PEMF in nerve function and skin perfusion of the dorsal foot. Although a reduction in average pain intensity score was not observed, subjects in the active group were relatively more compliant with device use. No device adverse effects were reported.