title: Symptom Severity of Restless Legs Syndrome Predicts Its Clinical Course.
abstract: OBJECTIVE
  This study examines the clinical course of restless legs syndrome according to its severity and factors associated with the remission of restless legs syndrome symptoms.
  
  
  METHODS
  The remission or persistence of restless legs syndrome symptoms was investigated by considering patients with restless legs syndrome at the sleep clinic of Seoul National University Bundang Hospital. All subjects were observed for at least 18 months, and an incidence of remission was defined as having no restless legs syndrome symptoms for at least 1 year. Restless legs syndrome severity was evaluated by the International Restless Legs Syndrome Study Group Rating Scale.
  
  
  RESULTS
  A total of 306 patients participated in this study. Over the observation periods of 4.1 ± 1.6 years, the cumulative incidence of remission is 32.5% (95% confidence interval [CI], 27.0-38.0) and decreased with baseline restless legs syndrome severity (P < .001): 60% (95% CI, 44.9-75.1), 44% (95% CI, 34.4-53.6), and 16.7% (95% CI, 10.6-22.8) in mild, moderate, and severe to very severe restless legs syndrome cases, respectively. Most cases of remission (82/96) were observed within 1 year, and the remission occurred sooner for mild restless legs syndrome. The hazard ratios of remission by Cox proportional hazards model were lower for moderate (0.556; 95% CI, 0.340-0.909) and severe to very severe (0.193; 95% CI, 0.108-0.343) restless legs syndrome than for mild restless legs syndrome. The remission incidence was lower for those patients who had a family history of restless legs syndrome and were older at restless legs syndrome diagnosis.
  
  
  CONCLUSIONS
  Mild restless legs syndrome severity, no family history, and young age at restless legs syndrome diagnosis were significant predictors of restless legs syndrome remission. More than 80% of patients with severe restless legs syndrome showed a chronic clinical course.
authors.affiliation: Department of Neuropsychiatry, Seoul National University Bundang Hospital, Seongnam, Republic of Korea.
authors.forename: Chung Suk
authors.initials: CS
authors.lastname: Lee
authors.affiliation: Department of Neuropsychiatry, Seoul National University Bundang Hospital, Seongnam, Republic of Korea; Department of Psychiatry, Kyung Hee University Hospital Hospital at Gangdong, Seoul, Republic of Korea.
authors.forename: Tae
authors.initials: T
authors.lastname: Kim
authors.affiliation: Department of Neuropsychiatry, Seoul National University Bundang Hospital, Seongnam, Republic of Korea.
authors.forename: Sumin
authors.initials: S
authors.lastname: Lee
authors.affiliation: Department of Neuropsychiatry, Seoul National University Bundang Hospital, Seongnam, Republic of Korea.
authors.forename: Hong Jun
authors.initials: HJ
authors.lastname: Jeon
authors.affiliation: Department of Neuropsychiatry, Seoul National University Bundang Hospital, Seongnam, Republic of Korea.
authors.forename: Young Rong
authors.initials: YR
authors.lastname: Bang
authors.affiliation: Department of Neuropsychiatry, Seoul National University Bundang Hospital, Seongnam, Republic of Korea; Department of Psychiatry, Seoul National University College of Medicine, Seoul, Republic of Korea. Electronic address: iyoon@snu.ac.kr.
authors.forename: In-Young
authors.initials: IY
authors.lastname: Yoon
mesh_terms: D000368:Aged; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D056910:Republic of Korea / Q000453:epidemiology; D012148:Restless Legs Syndrome / Q000453:epidemiology*; D012189:Retrospective Studies; D012720:Severity of Illness Index
keywords: Clinical course; Remission; Restless legs syndrome; Severity