Suppressed circadian heart rate dynamics in temporal lobe epilepsy.
OBJECTIVE
To measure interictal circadian rhythm of heart rate (HR) variability in patients with temporal lobe epilepsy (TLE) using a 24 hour ECG recording.


METHODS
Various conventional and dynamic fractal measures of HR variability were analysed in 17 patients with refractory TLE, 20 patients with well controlled TLE, and 37 healthy age and sex matched control subjects.


RESULTS
The SD of all RR intervals (p < 0.01), the measured power spectral components of HR variability (low frequency power (p < 0.01), high frequency power (p < 0.05)), and the SD1 (p < 0.05) and SD2 (p < 0.01) Poincaré two dimensional vector analysis measurements were suppressed in the patients. This suppression was observed during both day and night time; however, it was more pronounced at night, and nocturnal increase in HR variability usually seen in the normal population could not be detected in the patients. The HR variability measures did not correlate with the duration of epilepsy, the age of the patients, or with the anti-epileptic drugs used.


CONCLUSIONS
TLE was associated with reduced HR variability, which was more pronounced during night than day, and the nocturnal increase in HR variability was abolished in patients with TLE. The alteration in autonomic regulation of HR variability was similar in patients with both refractory and well controlled TLE.
Ronkainen
E
E
Department of Neurology, P.O.Box 5000, FIN-90014 University of Oulu, Finland. eronkain@student.oulu.fi
Ansakorpi
H
H
Huikuri
H V
HV
Myllylä
V V
VV
Isojärvi
J I T
JI
Korpelainen
J T
JT
D000328:Adult; D000927:Anticonvulsants / Q000627:therapeutic use; D002940:Circadian Rhythm / Q000502:physiology*; D004562:Electrocardiography; D004833:Epilepsy, Temporal Lobe / Q000188:drug therapy / Q000503:physiopathology*; D005260:Female; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D012720:Severity of Illness Index
D000927:Anticonvulsants