title: Periodic limb movements in sleep are followed by increases in EEG activity, blood pressure, and heart rate during sleep.
abstract: OBJECTIVE
  Periodic limb movements in sleep (PLMS) are related to arousal, sympathetic activation, and increases in blood pressure (BP), but whether they are part of the arousal process or causative of it is unclear. Our objective was to assess the temporal distribution of arousal-related measures around PLMS.
  
  
  METHODS
  Polysomnographic recordings of six patients with restless legs syndrome were analyzed. We analyzed 15 PLMS, plus three 5-s epochs before and after each movement, for every patient. Mean values per epoch of blood pressure (BP), heart rate (HR), and electroencephalographic (EEG) power were calculated. For each patient, six 5-s epochs of undisturbed sleep were analyzed as controls.
  
  
  RESULTS
  Alpha + beta EEG power, systolic BP, and HR were significantly increased following PLMS. The EEG power and HR increases were noticed in the first epoch after PLMS, whereas that of systolic BP was observed in the second and third epochs following a PLMS. No significant changes occurred in the epochs of undisturbed sleep.
  
  
  CONCLUSIONS
  The results suggest that PLMS are followed by arousal-related nervous system events. Given the high frequency of PLMS throughout the night, they could be a potential risk factor for nocturnal arrhythmias and hypertension, in addition to causing sleep deprivation.
authors.affiliation: Department of Adults' Neurology, Medical University of Gdansk, Ul. Debinki 7, 80-952, Gdansk, Poland. msiem@wp.pl.
authors.forename: Mariusz
authors.initials: M
authors.lastname: Sieminski
authors.affiliation: Department of Adults' Neurology, Medical University of Gdansk, Ul. Debinki 7, 80-952, Gdansk, Poland.
authors.forename: Jan
authors.initials: J
authors.lastname: Pyrzowski
authors.affiliation: Vitalmed Helsinki Sleep Clinic, Valimotie 21, Helsinki, 00380, Finland.
authors.forename: Markku
authors.initials: M
authors.lastname: Partinen
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000513:Alpha Rhythm; D001143:Arousal / Q000502:physiology; D001611:Beta Rhythm; D001794:Blood Pressure / Q000502:physiology*; D001921:Brain / Q000503:physiopathology; D004569:Electroencephalography; D005260:Female; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D020189:Nocturnal Myoclonus Syndrome / Q000175:diagnosis* / Q000503:physiopathology*; D017286:Polysomnography; D012148:Restless Legs Syndrome / Q000175:diagnosis* / Q000503:physiopathology*; D013564:Sympathetic Nervous System / Q000503:physiopathology
keywords: Blood pressure; Heart rate; Periodic limb movements; Polysomnography; Restless legs syndrome