Time- and state-dependent analysis of autonomic control in narcolepsy: higher heart rate with normal heart rate variability independent of sleep fragmentation.
Narcolepsy with hypocretin deficiency is known to alter cardiovascular control during sleep, but its aetiology is disputed. As cardiovascular control differs between sleep states, and narcolepsy affects sleep architecture, controlling for both duration and transitions of sleep states is necessary. This study therefore aimed to assess heart rate and its variability in narcolepsy during sleep taking these factors into account. The study included 12 medication-naïve patients with narcolepsy with cataplexy and hypocretin deficiency (11 male, 16-53 years old), and 12 sex- and age-matched healthy controls (11 male, 19-55 years). All subjects underwent 1-night ambulatory polysomnography recording. Cardiovascular parameters were calculated for each 30-s epoch. Heart rate was significantly higher in patients with narcolepsy than in controls in all sleep states and during wakefulness prior to sleep. Groups did not differ in heart rate variability measures. The effects of sleep state duration on heart rate and its variability were similar between patients and controls. In conclusion, heart rate was consistently higher in patients with narcolepsy than controls, independent of sleep stage and sleep fragmentation. A direct effect of hypocretin deficiency therefore seems probable.
Department of Neurology, Leiden University Medical Center, Leiden, The Netherlands; Department of Sleep and Cognition, Netherlands Institute for Neuroscience, Royal Netherlands Academy of Arts and Sciences, Amsterdam, The Netherlands.
Wisse P
WP
van der Meijden
Rolf
R
Fronczek
Robert H A M
RH
Reijntjes
Eleonora P M
EP
Corssmit
Nienke R
NR
Biermasz
Gert Jan
GJ
Lammers
J Gert
JG
van Dijk
Roland D
RD
Thijs
D000293:Adolescent; D000328:Adult; D001341:Autonomic Nervous System / Q000503:physiopathology*; D002385:Cataplexy / Q000150:complications* / Q000503:physiopathology*; D005260:Female; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000172:deficiency; D008297:Male; D008875:Middle Aged; D009479:Neuropeptides / Q000172:deficiency; D000068797:Orexins; D017286:Polysomnography; D012119:Respiration; D012892:Sleep Deprivation / Q000150:complications* / Q000503:physiopathology; D012894:Sleep Stages / Q000502:physiology; D013997:Time Factors; D014851:Wakefulness / Q000502:physiology; D055815:Young Adult
D047908:Intracellular Signaling Peptides and Proteins; D009479:Neuropeptides; D000068797:Orexins
hypocretin; orexin