title: REM sleep behaviour disorder is associated with lower fast and higher slow sleep spindle densities.
abstract: To investigate differences in sleep spindle properties and scalp topography between patients with rapid eye movement sleep behaviour disorder (RBD) and healthy controls, whole-night polysomnograms of 35 patients diagnosed with RBD and 35 healthy control subjects matched for age and sex were compared. Recordings included a 19-lead 10-20 electroencephalogram montage and standard electromyogram, electrooculogram, electrocardiogram and respiratory leads. Sleep spindles were automatically detected using a standard algorithm, and their characteristics (amplitude, duration, density, frequency and frequency slope) compared between groups. Topological analyses of group-discriminative features were conducted. Sleep spindles occurred at a significantly (e.g. t34 = -4.49; P = 0.00008 for C3) lower density (spindles ∙ min(-1) ) for RBD (mean ± SD: 1.61 ± 0.56 for C3) than for control (2.19 ± 0.61 for C3) participants. However, when distinguishing slow and fast spindles using thresholds individually adapted to the electroencephalogram spectrum of each participant, densities smaller (31-96%) for fast but larger (20-120%) for slow spindles were observed in RBD in all derivations. Maximal differences were in more posterior regions for slow spindles, but over the entire scalp for fast spindles. Results suggest that the density of sleep spindles is altered in patients with RBD and should therefore be investigated as a potential marker of future neurodegeneration in these patients.
authors.affiliation: Center for Advanced Research in Sleep Medicine, Hôpital du Sacré-Coeur de Montréal, Montreal, QC, Canada.|Département de psychiatrie, Université de Montréal, Montreal, QC, Canada.|Department of Neurology and Neurosurgery, McGill University, Montreal Neurological Institute, Montreal, QC, Canada.
authors.forename: Christian
authors.identifier: http://orcid.org/0000-0002-3149-4934
authors.initials: C
authors.lastname: O'Reilly
authors.affiliation: Center for Advanced Research in Sleep Medicine, Hôpital du Sacré-Coeur de Montréal, Montreal, QC, Canada.|Département de psychologie, Université de Montréal, Montreal, QC, Canada.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Godin
authors.affiliation: Center for Advanced Research in Sleep Medicine, Hôpital du Sacré-Coeur de Montréal, Montreal, QC, Canada.|Département de psychiatrie, Université de Montréal, Montreal, QC, Canada.
authors.forename: Jacques
authors.initials: J
authors.lastname: Montplaisir
authors.affiliation: Center for Advanced Research in Sleep Medicine, Hôpital du Sacré-Coeur de Montréal, Montreal, QC, Canada.|Département de psychiatrie, Université de Montréal, Montreal, QC, Canada.
authors.forename: Tore
authors.initials: T
authors.lastname: Nielsen
mesh_terms: D000465:Algorithms; D016022:Case-Control Studies; D004569:Electroencephalography; D004576:Electromyography; D004585:Electrooculography; D005215:Fasting; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017286:Polysomnography; D020187:REM Sleep Behavior Disorder / Q000503:physiopathology*; D012890:Sleep / Q000502:physiology*
keywords: Parkinson's disease; mild cognitive impairment; non rapid eye movement sleep; parasomnia; synucleinopathy