Autonomic function is impaired in elderly stroke survivors.
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.
McLaren
Andrew
A
Institute for Ageing and Health, Newcastle General Hospital, Westgate Road, Newcastle upon Tyne NE4 6BE. a.t.mclaren@ncl.ac.uk
Kerr
Simon
S
Allan
Louise
L
Steen
I Nicholas
IN
Ballard
Clive
C
Allen
John
J
Murray
Alan
A
Kenny
Rose Anne
RA
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