title: Autonomic function is impaired in elderly stroke survivors.
abstract: OBJECTIVE
  Impaired autonomic function is common in the acute poststroke phase but little is known about the longer term effects, particularly in older people. We sought to determine if autonomic function is impaired after stroke recovery in older patients.
  
  
  METHODS
  A cross-sectional case-control study comparing autonomic function in 76 nondemented stroke patients with 70 community-living controls aged older than 75 years.
  
  
  RESULTS
  Cases were assessed on average 9 months after stroke. From power spectral analysis of heart rate variability, stroke patients had lower total (P=0.032) and low-frequency (P=0.014) spectral densities and impaired baroreflex sensitivity (alpha low-frequency baroreflex sensitivity, P=0.006). From a series of cardiovascular autonomic reflex tests, heart rate variation during forced respiration, Valsalva ratio, and blood pressure overshoot during Valsalva maneuver were significantly lower in stroke patients (P=0.003, <0.001, and 0.027, respectively). Blood pressure response to isometric exercise was significantly exaggerated in stroke patients (P=0.007).
  
  
  CONCLUSIONS
  Cardiovascular autonomic function is impaired long after the index event in stroke survivors. Impaired autonomic function may increase the risk of all-cause mortality and cardiovascular mortality in older stroke survivors.
authors.affiliation: Institute for Ageing and Health, Newcastle General Hospital, Westgate Road, Newcastle upon Tyne NE4 6BE. a.t.mclaren@ncl.ac.uk
authors.forename: Andrew
authors.initials: A
authors.lastname: McLaren
authors.forename: Simon
authors.initials: S
authors.lastname: Kerr
authors.forename: Louise
authors.initials: L
authors.lastname: Allan
authors.forename: I Nicholas
authors.initials: IN
authors.lastname: Steen
authors.forename: Clive
authors.initials: C
authors.lastname: Ballard
authors.forename: John
authors.initials: J
authors.lastname: Allen
authors.forename: Alan
authors.initials: A
authors.lastname: Murray
authors.forename: Rose Anne
authors.initials: RA
authors.lastname: Kenny
mesh_terms: D000368:Aged; D001341:Autonomic Nervous System / Q000503:physiopathology*; D017704:Baroreflex; D001794:Blood Pressure; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D005260:Female; D006321:Heart / Q000294:innervation*; D006339:Heart Rate; D006801:Humans; D008297:Male; D020521:Stroke / Q000175:diagnosis / Q000503:physiopathology*; D017741:Survivors