Vibration and skin blood flow changes in subjects with restless legs syndrome

Abstract

Objective: Vascular disturbances leading to tissue hypoxia have been named as one of the possible causes of restless legs syndrome (RLS). Whole body vibration (WBV) in healthy individuals results in nitric oxide (NO) generation, which then leads to increased blood flow. The purpose of this investigation was to determine if WBV can: 1) improve skin blood flow, as measured in flux, in individuals with RLS, and 2) induce increases in NO blood concentration. The data were compared to healthy age-matched subjects. Design: Repeated measures, using two groups (RLS and control) that underwent two treatments (WBV) and sham (no vibration). Setting: Data collection occurred in an institutional setting. Patients: Ten subjects with RLS and ten controls. Methods: Subjects underwent a ten bout, 30-second per bout WBV and one sham treatment session. Blood drawn for NO analysis and flux measurements with laser Doppler were performed before, immediately after, and 5 minutes after the sessions. Main outcome measurements: The dependent variables, measured at three time intervals, were skin blood flow (flux) as determined by laser Doppler imaging and blood nitric oxide concentration. Results: Baseline flux was significantly higher in the RLS group compared to control (P<0.001); flux in the RLS group immediately after WBV was significantly higher compared to baseline (P<0.05), sham treatment (P<0.05), and control group (P<0.05). There was no difference in NO concentration within subjects and between groups. Conclusion: Subjects with RLS have higher skin blood flow than controls and a greater increase in flux with WBV without concurrent increases in NO concentration from blood drawn at the antecubital fossa.