title: The prevalence of restless legs syndrome across the full spectrum of kidney disease.
abstract: OBJECTIVE
  Although restless legs syndrome (RLS) is common and well recognized as an important and potentially treatable cause of sleep disruption in end-stage renal disease (ESRD), few studies have evaluated the prevalence of RLS and its impact on sleep in the non-dialysis-dependent chronic kidney disease (CKD) population. The objectives of the study were to determine the prevalence of RLS across the full spectrum of kidney disease and to assess the impact of RLS on sleep quality and daytime function.
  
  
  METHODS
  Five hundred patients were recruited from nephrology clinics and were stratified according to estimated glomerular filtration rate (EGFR): eGFR ≥ 60 mL/min/1.73m(2) (n = 127), CKD (eGFR < 60, not on dialysis, n = 242), and ESRD (on hemodialysis, n = 131). All subjects completed a sleep and medical history questionnaire, an RLS questionnaire, the Pittsburgh Sleep Quality Index (PSQI), and the Epworth Sleepiness Scale (ESS).
  
  
  RESULTS
  The prevalence of RLS did not differ among the three groups (18.9% [eGFR ≥ 60], 26% (CKD), and 26% (ESRD) p = 0.27). However, many symptoms of sleep disruption were more common in patients with RLS, and RLS was independently correlated with the PSQI score both in the full cohort (OR = 2.63, CI = 1.60-4.00, p < 0.001) and the CKD group (OR = 2.39, CI = 1.20-4.79, p = 0.014).
  
  
  CONCLUSIONS
  RLS is common in non-dialysis-dependent CKD patients and is an important source of sleep disruption.
authors.affiliation: Department of Medicine, Faculty of Medicine, University of Calgary, Calgary, AB, Canada.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Lee
authors.forename: David D M
authors.initials: DD
authors.lastname: Nicholl
authors.forename: Sofia B
authors.initials: SB
authors.lastname: Ahmed
authors.forename: Andrea H S
authors.initials: AH
authors.lastname: Loewen
authors.forename: Brenda R
authors.initials: BR
authors.lastname: Hemmelgarn
authors.forename: Jaime M
authors.initials: JM
authors.lastname: Beecroft
authors.forename: Tanvir C
authors.initials: TC
authors.lastname: Turin
authors.forename: Patrick J
authors.initials: PJ
authors.lastname: Hanly
mesh_terms: D000203:Activities of Daily Living; D000328:Adult; D000368:Aged; D000416:Alberta / Q000453:epidemiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D011788:Quality of Life; D051436:Renal Insufficiency, Chronic / Q000453:epidemiology*; D012148:Restless Legs Syndrome / Q000453:epidemiology*; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires
keywords: Restless legs syndrome; chronic kidney disease; daytime sleepiness; end-stage renal disease; prevalence; sleep quality