Comparison of sleep EEG profiles of patients suffering from restless legs syndrome, restless legs syndrome and depressive symptoms, and major depressive disorders

BACKGROUND: Depressive disorders and restless legs syndrome (RLS) demand particular attention because sleepiness, daytime fatigue and loss of interest are symptoms attributable to both depressive disorders and RLS. Moreover, a high comorbidity rate is observed. The aim of the present study was to compare polysomnographic data of patients suffering from RLS, RLS and depressive symptoms, and major depressive disorders (MDD). METHODS: Sleep EEG recordings of patients suffering from RLS (n = 25), RLS and depressive symptoms (n = 38), as well as MDD (n = 15) were compared. RESULTS: Compared to patients with MDD, both groups with RLS had statistically decreased values of sleep continuity, including sleep efficiency, sleep onset latency and wakening after sleep onset. Patients with RLS or RLS and depressive symptoms had also decreased slow-wave sleep compared to patients with MDD. CONCLUSIONS: Objective sleep assessment supports previous findings: RLS is a disorder seriously affecting sleep, even compared to MDD. Concomitant symptoms of depression do not seem to additionally deteriorate sleep, though they trigger differences in treatment.