Sleep laboratory studies in restless legs syndrome patients as compared with normals and acute effects of ropinirole 1. Findings on objective and subjective sleep and awakening quality

Although the restless legs syndrome (RLS) is a disorder with a relatively h igh prevalence rate (8% in Austria) and leads to insomnia and excessive day time tiredness, there is a paucity of sleep laboratory data concerning obje ctive and subjective sleep and awakening quality. Thus, the aim of this stu dy was to investigate 12 untreated RLS patients as compared with 12 normal controls and subsequently measure the acute effects of 0.5 mg ropinirole (R equip(R)) - a nonergoline dopamine agonist - as compared with placebo. In 3 nights (adaptation, placebo, ropinirole night) sleep induction, maintenanc e and architecture were measured objectively by polysomnography, subjective sleep and awakening quality were assessed by self-rating scales and visual -analog scales, and objective awakening quality was evaluated by a psychome tric test battery. In polysomnography, RLS patients demonstrated, as compar ed with normal controls, a decreased total sleep time (TST) and sleep effic acy, increased wakefulness during the total sleep period and frequency of n octurnal awakenings, increased sleep stage S1, decreased S2 and increased s tage shifts. Subjective sleep quality tended to decrease, and morning well- being, mood, affectivity and wakefulness were deteriorated. In the noopsych e, fine motor activity and reaction time performance were deteriorated. Rop inirole 0.5 mg induced, as compared with placebo, an increase in TST, sleep efficacy, S2 sleep and stage shifts. In the morning, somatic complaints in creased slightly, while fine motor activity and reaction time performance i mproved. Our findings suggest a key-lock. principle in the diagnosis/treatm ent of RLS and a dopaminergic mechanism in its pathogenesis, which is suppo rted by the data on periodic leg movements during sleep and arousals of the subsequent paper. Copyright (C) 2000 S. Karger AG, Basel.