NREM sleep alterations in narcolepsy/cataplexy

Raffaele Ferri, Silvia Miano, Oliviero Bruni, Jitka Vankova, Sona Nevsimalova, Stefano Vandi, Pasquale Montagna, Luigi Ferini-Strambi, Giuseppe Plazzi

Research output: Contribution to journalArticle

50 Citations (Scopus)

Abstract

Objective: NREM sleep patterns of narcoleptic patients with cataplexy were studied, focusing on their sleep 'microstructure', by analyzing the cyclic alternating pattern (CAP). Methods: Forty-nine HLA DQB1*0602-positive patients with narcolepsy/cataplexy (32 men and 17 women, aged 18-46 years) were included together with 37 age-matched normal controls. Each subject underwent one polysomnographic night recording after an adaptation night. Sleep stages were scored following standard criteria and CAP A phases were detected and classified into 3 subtypes (A1, A2, and A3). Power spectra for frequencies between 0.5 and 25 Hz were obtained for each CAP condition, separately in sleep stage 2 and SWS. Results: Narcoleptic patients displayed reduced total CAP rate. A selective reduction in the number of A1 subtypes/hour and a reduced A3 index were found in narcoleptics who had also a smaller average number of CAP sequences. Narcoleptic patients had higher power spectra for fast frequencies mostly during SWS, while REM sleep power spectra showed significantly higher power density for frequency bins 0.5-1.5, 8.5-9.5, and 17.5-25 Hz. Similarly, CAP A1 subtypes and NCAP epochs during SWS displayed significantly higher power density for fast frequency bins. Conclusions: The main finding of this study is that the occurrence of the A1 CAP subtypes is impaired during NREM sleep in narcoleptic patients. Thus, narcolepsy seems to be accompanied not only by alterations of REM but also NREM sleep which is subtly but significantly impaired, as reflected by CAP and the corresponding EEG spectral analysis. Significance: Our findings might indicate that in narcolepsy very-slow oscillation processes less effective than normal might be present, with a subtly impaired capability of grouping the other sleep EEG activities; this aspect deserves further insight in order to obtain a better understanding of its functional meaning.

Original languageEnglish
Pages (from-to)2675-2684
Number of pages10
JournalClinical Neurophysiology
Volume116
Issue number11
DOIs
Publication statusPublished - Nov 2005

Fingerprint

Cataplexy
Narcolepsy
Sleep
Sleep Stages
Electroencephalography
REM Sleep
varespladib methyl

Keywords

  • Cyclic alternating pattern
  • EEG spectral analysis
  • Narcolepsy
  • NREM sleep
  • Sleep microstructure

ASJC Scopus subject areas

  • Clinical Neurology
  • Radiology Nuclear Medicine and imaging
  • Neurology
  • Sensory Systems
  • Physiology (medical)

Cite this

NREM sleep alterations in narcolepsy/cataplexy. / Ferri, Raffaele; Miano, Silvia; Bruni, Oliviero; Vankova, Jitka; Nevsimalova, Sona; Vandi, Stefano; Montagna, Pasquale; Ferini-Strambi, Luigi; Plazzi, Giuseppe.

In: Clinical Neurophysiology, Vol. 116, No. 11, 11.2005, p. 2675-2684.

Research output: Contribution to journalArticle

Ferri, Raffaele ; Miano, Silvia ; Bruni, Oliviero ; Vankova, Jitka ; Nevsimalova, Sona ; Vandi, Stefano ; Montagna, Pasquale ; Ferini-Strambi, Luigi ; Plazzi, Giuseppe. / NREM sleep alterations in narcolepsy/cataplexy. In: Clinical Neurophysiology. 2005 ; Vol. 116, No. 11. pp. 2675-2684.
@article{6b10cc20daac4d4dbe50412df89588a8,
title = "NREM sleep alterations in narcolepsy/cataplexy",
abstract = "Objective: NREM sleep patterns of narcoleptic patients with cataplexy were studied, focusing on their sleep 'microstructure', by analyzing the cyclic alternating pattern (CAP). Methods: Forty-nine HLA DQB1*0602-positive patients with narcolepsy/cataplexy (32 men and 17 women, aged 18-46 years) were included together with 37 age-matched normal controls. Each subject underwent one polysomnographic night recording after an adaptation night. Sleep stages were scored following standard criteria and CAP A phases were detected and classified into 3 subtypes (A1, A2, and A3). Power spectra for frequencies between 0.5 and 25 Hz were obtained for each CAP condition, separately in sleep stage 2 and SWS. Results: Narcoleptic patients displayed reduced total CAP rate. A selective reduction in the number of A1 subtypes/hour and a reduced A3 index were found in narcoleptics who had also a smaller average number of CAP sequences. Narcoleptic patients had higher power spectra for fast frequencies mostly during SWS, while REM sleep power spectra showed significantly higher power density for frequency bins 0.5-1.5, 8.5-9.5, and 17.5-25 Hz. Similarly, CAP A1 subtypes and NCAP epochs during SWS displayed significantly higher power density for fast frequency bins. Conclusions: The main finding of this study is that the occurrence of the A1 CAP subtypes is impaired during NREM sleep in narcoleptic patients. Thus, narcolepsy seems to be accompanied not only by alterations of REM but also NREM sleep which is subtly but significantly impaired, as reflected by CAP and the corresponding EEG spectral analysis. Significance: Our findings might indicate that in narcolepsy very-slow oscillation processes less effective than normal might be present, with a subtly impaired capability of grouping the other sleep EEG activities; this aspect deserves further insight in order to obtain a better understanding of its functional meaning.",
keywords = "Cyclic alternating pattern, EEG spectral analysis, Narcolepsy, NREM sleep, Sleep microstructure",
author = "Raffaele Ferri and Silvia Miano and Oliviero Bruni and Jitka Vankova and Sona Nevsimalova and Stefano Vandi and Pasquale Montagna and Luigi Ferini-Strambi and Giuseppe Plazzi",
year = "2005",
month = "11",
doi = "10.1016/j.clinph.2005.08.004",
language = "English",
volume = "116",
pages = "2675--2684",
journal = "Clinical Neurophysiology",
issn = "1388-2457",
publisher = "Elsevier Ireland Ltd",
number = "11",

}

TY - JOUR

T1 - NREM sleep alterations in narcolepsy/cataplexy

AU - Ferri, Raffaele

AU - Miano, Silvia

AU - Bruni, Oliviero

AU - Vankova, Jitka

AU - Nevsimalova, Sona

AU - Vandi, Stefano

AU - Montagna, Pasquale

AU - Ferini-Strambi, Luigi

AU - Plazzi, Giuseppe

PY - 2005/11

Y1 - 2005/11

N2 - Objective: NREM sleep patterns of narcoleptic patients with cataplexy were studied, focusing on their sleep 'microstructure', by analyzing the cyclic alternating pattern (CAP). Methods: Forty-nine HLA DQB1*0602-positive patients with narcolepsy/cataplexy (32 men and 17 women, aged 18-46 years) were included together with 37 age-matched normal controls. Each subject underwent one polysomnographic night recording after an adaptation night. Sleep stages were scored following standard criteria and CAP A phases were detected and classified into 3 subtypes (A1, A2, and A3). Power spectra for frequencies between 0.5 and 25 Hz were obtained for each CAP condition, separately in sleep stage 2 and SWS. Results: Narcoleptic patients displayed reduced total CAP rate. A selective reduction in the number of A1 subtypes/hour and a reduced A3 index were found in narcoleptics who had also a smaller average number of CAP sequences. Narcoleptic patients had higher power spectra for fast frequencies mostly during SWS, while REM sleep power spectra showed significantly higher power density for frequency bins 0.5-1.5, 8.5-9.5, and 17.5-25 Hz. Similarly, CAP A1 subtypes and NCAP epochs during SWS displayed significantly higher power density for fast frequency bins. Conclusions: The main finding of this study is that the occurrence of the A1 CAP subtypes is impaired during NREM sleep in narcoleptic patients. Thus, narcolepsy seems to be accompanied not only by alterations of REM but also NREM sleep which is subtly but significantly impaired, as reflected by CAP and the corresponding EEG spectral analysis. Significance: Our findings might indicate that in narcolepsy very-slow oscillation processes less effective than normal might be present, with a subtly impaired capability of grouping the other sleep EEG activities; this aspect deserves further insight in order to obtain a better understanding of its functional meaning.

AB - Objective: NREM sleep patterns of narcoleptic patients with cataplexy were studied, focusing on their sleep 'microstructure', by analyzing the cyclic alternating pattern (CAP). Methods: Forty-nine HLA DQB1*0602-positive patients with narcolepsy/cataplexy (32 men and 17 women, aged 18-46 years) were included together with 37 age-matched normal controls. Each subject underwent one polysomnographic night recording after an adaptation night. Sleep stages were scored following standard criteria and CAP A phases were detected and classified into 3 subtypes (A1, A2, and A3). Power spectra for frequencies between 0.5 and 25 Hz were obtained for each CAP condition, separately in sleep stage 2 and SWS. Results: Narcoleptic patients displayed reduced total CAP rate. A selective reduction in the number of A1 subtypes/hour and a reduced A3 index were found in narcoleptics who had also a smaller average number of CAP sequences. Narcoleptic patients had higher power spectra for fast frequencies mostly during SWS, while REM sleep power spectra showed significantly higher power density for frequency bins 0.5-1.5, 8.5-9.5, and 17.5-25 Hz. Similarly, CAP A1 subtypes and NCAP epochs during SWS displayed significantly higher power density for fast frequency bins. Conclusions: The main finding of this study is that the occurrence of the A1 CAP subtypes is impaired during NREM sleep in narcoleptic patients. Thus, narcolepsy seems to be accompanied not only by alterations of REM but also NREM sleep which is subtly but significantly impaired, as reflected by CAP and the corresponding EEG spectral analysis. Significance: Our findings might indicate that in narcolepsy very-slow oscillation processes less effective than normal might be present, with a subtly impaired capability of grouping the other sleep EEG activities; this aspect deserves further insight in order to obtain a better understanding of its functional meaning.

KW - Cyclic alternating pattern

KW - EEG spectral analysis

KW - Narcolepsy

KW - NREM sleep

KW - Sleep microstructure

UR - http://www.scopus.com/inward/record.url?scp=27544484813&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=27544484813&partnerID=8YFLogxK

U2 - 10.1016/j.clinph.2005.08.004

DO - 10.1016/j.clinph.2005.08.004

M3 - Article

C2 - 16221567

AN - SCOPUS:27544484813

VL - 116

SP - 2675

EP - 2684

JO - Clinical Neurophysiology

JF - Clinical Neurophysiology

SN - 1388-2457

IS - 11

ER -