Journal: The Clinical Journal of Pain. 2007. May;23(4):316-322.
Authors and affiliations: Wang K, Svensson P, Arendt-Nielsen L. Center for Sensory-Motor Interaction, Orofacial Pain Laboratory, Aalborg University, Aalborg, Denmark; Department of Clinical Oral Physiology, School of Dentistry, University of Aarhus, Aarhus, Denmark. [E-mail: email@example.com ]
Objective: The aim of this study was to examine the effect of acupuncture-like electrical stimulation on chronic tension-type headache (TTH) in a randomized, double-blinded, placebo-controlled study.
Methods: Thirty-six patients (18 men, 18 women) with chronic TTH in accordance with the criteria of International Headache Society were investigated. The patients were randomly assigned into 2 groups: a treatment group and a placebo group.
Pain duration, pain intensity on a 0 to 10 cm visual analog scale, number of headache attacks, and use of medication were recorded in a diary for 2 weeks before treatment (baseline), early stage of treatment (Treat-1; 2 wk), late stage of treatment (Treat-2; 4 wk), and after the end of treatment (Post-1, Post-2, Post-3 corresponding to 2, 4, and 6-wk follow-up). The patients also provided an overall evaluation of the treatment effect at each stage.
Patients were taught how to use either an acupuncture-like electrical stimulator or a sham stimulator (identical but incapable of delivering an electric current) and then instructed to use the device at home.
Six acupoints, bilateral EX-HN5, GB 20, LI 4, were selected to be stimulated 3 minutes for each point, twice a day. Friedman repeated measure analysis of variance on rank was used to test the data.
Results: The pain duration was shortened at Treat-1 and pain intensity was decreased at Treat-1 and Treat-2 compared with baseline. The overall evaluation of the 2 treatments indicated improvements in both the treatment and the placebo groups, but with no significant difference between the groups (P>0.061).
Despite the apparent improvement in both the treatment and placebo groups, a decrease in analgesic use was only observed in the treatment group. There was also a significant positive correlation between the reported intensity of the stimulus-evoked sensation and the evaluation of the effect of either active or placebo treatments (P=0.039).
Conclusions: The use of acupuncture-like electrical stimulation was not associated with significant adverse effects. These results indicate that acupuncture-like electrical stimulation is a safe and potentially analgesic-sparing therapy that may be considered as an adjunctive treatment for patients with chronic TTH although the clinical effect on pain seems to be marginal in the present set-up.