Sleep improvement for restless legs syndrome patients. Part I: pooled analysis of two prospective, double-blind, sham-controlled, multi-center, randomized clinical studies of the effects of vibrating pads on RLS symptoms

Fred Burbank,¹ Mark J Buchfuhrer,² Branko Kopjar<sup>3

1</sup>Salt Creek International Women’s Health Foundation, San Clemente, CA, USA; ²Stanford University Center for Sleep Sciences, Downey, CA, USA; ³Department of Health Services, University of Washington, Seattle, WA, USA

Purpose: Pooled data from two randomized, double-blind, prospective clinical trials were analyzed (i) to determine if vibratory stimulation can safely treat patients with moderately severe restless legs syndrome and (ii) to compare two types of shams.
Patients and methods: One hundred and fifty-eight patients with at least moderately severe primary restless legs syndrome (a score of 15 or greater on the International Restless Legs Syndrome Study Group rating scale) were enrolled at five investigational sites, between April 20, 2009 and February 12, 2010. Patients were randomly assigned to treatment with a vibrating pad or control (sound-producing or light-emitting sham pad). Patients and investigators were blinded to pad assignment type (treatment pad or sham pad). Efficacy was measured as a change in score from baseline to week 4, on the Medical Outcomes Study Sleep Problems Index II, the Johns Hopkins Restless Legs Syndrome Quality of Life summary scale, and the International Restless Legs Syndrome Study Group rating scale. Clinicians were asked to evaluate the effectiveness of the pad assignment and to guess whether treatment or sham therapy had been assigned. Adverse events related to vibrating pad assignment were tabulated.
Results: The Medical Outcomes Study Sleep Problems Index II scores improved significantly more for patients receiving a vibrating pad over those receiving a sham pad (P ≤ 0.02) even when corrected for multiplicity (P ≤ 0.04). Clinician evaluation favored patients assigned vibrating pads, and neither patients nor clinicians accurately guessed which pad was assigned. No significant difference in adverse event rates was observed between the vibrating and sham pad groups. Sound and light sham pads performed comparably with respect to safety and efficacy.
Conclusion: Four weeks of treatment with vibrating pads safely improved sleep in patients with restless legs syndrome and both shams functioned comparably.

Keywords: restless legs syndrome, vibration therapy, sham-controlled, double-blind, randomized clinical trial