Autonomic dysfunction in restless legs syndrome

Objective Autonomic dysfunction in patients with RLS has been described in some domains; however, detailed studies on this subject are limited and report conflicting results. In this study, we aimed to evaluate autonomic functions electrophysiologically and clinically in patients with restless legs syndrome (RLS). Methods Fifty-two adult patients with RLS and 40 healthy controls were enrolled in this prospective study. Electrophysiological tests of sympathetic skin response (SSR) and RR interval variability (RRIV) analysis were performed, and the SCOPA-AUT questionnaire was applied to evaluate autonomic functions. Results There was no significant difference in terms of SSR results between patients and controls (p > 0.05). However, there were significant differences between the patient and control groups in terms of RRIV analyses at rest, deep breathing, and valsalva, and also valsalva ratio (p = 0.037,p = 0.049,p = 0.017,p = 0.020). The mean SCOPA-AUT total score was higher in the RLS group compared with the control group (20.7 +/- 10 vs 14.2 +/- 8;p = 0.003). Significant differences were found regarding gastrointestinal, urinary, and cardiovascular domains (p = 0.01,p = 0.007,p = 0.049); on the other hand, pupillomotor, thermoregulatory, and sexual function did not significantly differ (p > 0.05). Conclusion Autonomic functions should be questioned in detail as well as motor and sensory symptoms of RLS, and care should be taken especially on cardiac dysfunction.