Diabetic peripheral neuropathy: amelioration of pain with transcutaneous electrostimulation

To evaluate the efficacy of transcutaneous electrotherapy for chronic painful peripheral neuropathy in patients with type 2 diabetes.

Thirty-one patients with symptoms and signs of peripheral neuropathy were randomized to the electrotherapy or sham treatment (control) group. The electrostimulation was given by a portable unit (H-Wave machine) than generated a biphasic, exponentially decaying waveform (pulse width 4 ms, 25-35 V, > or = 2 Hz). Patients treated each of their lower extremities for 30 min daily for 4 weeks at home. Nine patients from the sham-treatment group participated for a second period, during which all of them received the active electrotherapy. Patient's degree of pain and discomfort was graded on a scale of 0 to 5.

In the sham-treated group (n = 13), the neuropathic symptoms improved in five (38%) patients, and the pain score declined from 2.92 +/- 0.13 to 2.38 +/- 0.26 (P < 0.04), suggesting a procedure-related placebo effect. In the electrotherapy group (n = 18), symptomatic improvement was seen in 15 (83%) cases, 3 of which were completely asymptomatic; the pain score declined from 3.17 +/- 0.12 to 1.44 +/- 0.25 (P < 0.01) and the posttreatment pain scores were considerably lower (P < 0.03), indicating a substantial treatment effect over and above any placebo influence. Patients in the electrotherapy group reported greater reduction in symptoms (52 +/- 7% vs. 27 +/- 10% in control subjects, P < 0.05) on an analog scale. Moreover, the electrotherapy decreased pain scores (from 3.0 +/- 0.62 to 1.56 +/- 0.32, P < 0.02) in nine patients who had received sham treatment earlier.

A form of transcutaneous electrotherapy ameliorated the pain and discomfort associated with peripheral neuropathy. This novel modality offers a potential non-pharmacological treatment option.