title: Periodic leg movements in narcolepsy patients: impact on sleep architecture.
abstract: BACKGROUND
  We assessed the effect of periodic leg movements (PLMs) on sleep architecture in narcolepsy patients by comparing sleep patterns in narcoleptics of comparable age with and without PLMs.
  
  
  METHODS
  Patients diagnosed with narcolepsy between January 1999 and December 2005 were divided into those with PLM index >or= 5/hr and <5/hr. Each patient underwent polysomnographic recording followed by a multiple sleep latency test (MSLT).
  
  
  RESULTS
  There were 47 patients, of mean age 28.9 +/- 1.8 years, 31 (66%) with PLM index >or= 5/hr and 16 (34%) with PLM index <5/hr. Arousal index, PLM arousals and total number of arousals were all significantly higher in narcoleptics with PLM index >or= 5/hr than in those with PLM index <5/hr. Significant correlations were found between PLM index and arousal index, stage shifts, Stage 1 and average sleep latency on MSLT.
  
  
  CONCLUSIONS
  Our findings demonstrated that narcolepsy patients with PLMs have a higher arousal index and increased PLM arousals compared with narcolepsy patients without PLMs. The contribution of the above to the perceived sleep quality and daytime sleepiness is not clear.
authors.affiliation: Sleep Disorders Center, King Saud University, Riyadh, Saudi Arabia. ashammam2@gmail.com
authors.forename: A
authors.initials: A
authors.lastname: Bahammam
mesh_terms: D000328:Adult; D001143:Arousal; D005260:Female; D006801:Humans; D008297:Male; D009290:Narcolepsy / Q000150:complications / Q000503:physiopathology*; D020189:Nocturnal Myoclonus Syndrome / Q000209:etiology / Q000503:physiopathology*; D017286:Polysomnography; D012894:Sleep Stages