Session Title: Restless Leg Syndrome, RBD and Other Sleep Disorders
Session Time: 1:45pm-3:15pm
Location: Les Muses Terrace, Level 3
Objective: To investigate REM density in patients with isolated REM sleep without atonia.
Background: Isolated RSWA (iRSWA) is regarded as a prodromal phase of REM sleep behavior disorder and subsequently of an underlying synucleinopathy (e.g. Parkinson’s disease) . Defining a polysomnographic phenotype of iRSWA patients, with the focus on prodromal PD variables, is important for improving RSWA diagnosis. One of the polysomnographic variables is REM density: the number of Rapid Eye Movements per hour during REM sleep. REM density is typically decreased in PD  and increased in patients with major depression  and narcolepsy . In this study, we have evaluated REM density in iRSWA patients.
Method: We compared REM density in 50 iRSWA patients with 40 control individuals. All subjects underwent a classic video polysomnography and a clinical assessment. RSWA and other sleep parameters were scored according to the AASM manual. REM density was calculated automatically (REM/hour). Differences between groups were calculated using a univariate GLM, adjusted for age and gender. Correlations between REM density and both phasic and tonic RSWA percentage were calculated with Pearson’s correlation coefficient, adjusted for age and gender.
Results: Mean REM density was 343.9 ± 112.5 in the iRSWA group and 266.5 ± 92.1 in the control group (p=0.001). Furthermore, we found a positive correlation between REM density and phasic RSWA (r=0.36, P=0.001) as well as tonic RSWA (r=0.23, P=0.032).
Conclusion: These findings suggest that an increase in RSWA is associated with an increase in REM density and both variables probably share an overlapping pathophysiology.
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To cite this abstract in AMA style:F. Dijkstra, M. Viaene, I. de Volder, P. Cras, D. Crosiers. REM density in isolated REM sleep without atonia [abstract]. Mov Disord. 2019; 34 (suppl 2). https://www.mdsabstracts.org/abstract/rem-density-in-isolated-rem-sleep-without-atonia/. Accessed November 29, 2023.
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