Percutaneous electrical nerve stimulation - A novel analgesic therapy for diabetic neuropathic pain

OBJECTIVE - To evaluate the use of percutaneous electrical nerve stimulatio n (PENS) in the management of patients with painful diabetic peripheral neu ropathy. RESEARCH DESIGN AND METHODS - A total of 50 adult patients with type 2 diab etes and peripheral neuropathic pain of >6 months duration involving the lo wer extremities were randomly assigned to receive active PENS (needles with electrical stimulation at an alternating frequency of 15 and 30 nz) and sh am (needles only) treatments for 3 weeks. Each series of treatments was adm inistered for 30 min three times a week according to a standardized protoco l. After a 1-week washout period, all patients were subsequently switched t o the other modality A 10-cm visual analog scale (VAS) was used to assess p ain, physical activity and quality of sleep before each session. The change s in VAS scores and daily requirements for oral analgesic medication were d etermined during each 3-week treatment period. Patients completed the MOS 3 6-Item Short-Form Health Survey (SF-36), the Beck Depression Inventory (BDI ), and the Profile of Mood States (POMS) before and after completion of eac h treatment modality. At the end of the crossover study, a patient preferen ce questionnaire was used to compare the effectiveness of the two modalitie s. RESULTS - Compared with the pain VAS scores before active (6.2 +/- 1.0) and sham (6.4 +/- 0.9) treatments, pain scores after treatment were reduced to 2.5 +/- 0.8 and 6.3 +/- 1.1, respectively With active PENS treatment, the VAS activity and sleep scores were significantly improved from 5.2 +/- 1.0 and 5.8 +/- 1.3 to 7.9 +/- 1.0 and 8.3 +/- 0.7, respectively The VAS scores for pain, activity, and sleep were unchanged from baseline values after th e sham treatments. Patients' daily oral nonopioid analgesic requirements de creased by 49 and 14% after active and sham PENS treatments, respectively T he post-treatment physical and mental components of the SF-36, the BDI, and the POMS all Showed a significantly greater improvement with active versus sham treatments. Active PENS treatment improved the neuropathic pain sympt oms in all patients. CONCLUSIONS - PENS is a useful nonpharmacological therapeutic modality for treating diabetic neuropathic pain. In addition to decreasing extremity pai n, PENS therapy improved physical activity: sense of well-being, and qualit y of sleep while reducing the need for oral nonopioid analgesic medication.