Title
EMG variance during polysomnography as an assessment for REM sleep behavior disorder
Document Type
Article
Publication Date
12-2007
Abstract
Study Objectives:
In a previous study, we validated a polysomnographic assessment for REM sleep behavior disorder (RBD). The method proved to be reliable but required slow, labor-intensive visual scoring of surface electromyogram (EMG) activity. We therefore developed a computerized metric to assess EMG variance and compared the results to those previously published for visual scoring, bed partner-rated RBD symptom scores, and clinical assessments by sleep medicine specialists.
Design:
Retrospective validation of new computer algorithm
Setting:
Sleep research laboratory
Participants:
Twenty-three subjects: 17 with neurodegenerative disorders (9 with probable or possible RBD), and 6 controls.
Interventions:
N/A
Methods:
We visually scored 2 consecutive nocturnal polysomnograms for each subject. A computer algorithm calculated the variance of the chin EMG during all 3-second mini-epochs, and compared variances during REM sleep to a threshold defined by variances during quiet NREM sleep. The percentage of all REM mini-epochs with variance above this threshold created a metric, which we refer to as the supra-threshold REM EMG activity metric (STREAM) for each subject.
Results:
The STREAM correlated highly with the visually-derived score for RBD severity (Spearman rho = 0.87, P < 0.0001). A clinical impression of probable or possible RBD was associated to a similar extent with both STREAM (Wilcoxon rank sum test, P = 0.009) and the visually-derived score (P = 0.018). An optimal STREAM cutoff identified probable or possible RBD with 100% sensitivity and 71% specificity. The RBD symptom score correlated with both STREAM (rho = 0.42, P = 0.046) and the visual score (rho = 0.42, P = 0.048).
Conclusions:
These results suggest that a new, automated assessment for RBD may provide as much utility as a more time-consuming manual approach.
Publication Title
Sleep
Recommended Citation
Burns, J. W.,
Consens, F. B.,
Little, R. J.,
Angell, K. J.,
Gilman, S.,
&
Chervin, R. D.
(2007).
EMG variance during polysomnography as an assessment for REM sleep behavior disorder.
Sleep,
30(12), 1771-1778.
http://doi.org/10.1093/sleep/30.12.1771
Retrieved from: https://digitalcommons.mtu.edu/mtri_p/44
Publisher's Statement
© 2007 American Academy of Sleep Medicine. Publisher's version of record: http:/doi.org/10.1093/sleep/30.12.1771