Objective: Increased muscle activity during rapid eye movement (REM) sleep (i.e. REM sleep without atonia) is common in people with Parkinson's disease (PD). This study tested the hypotheses that people with PD and REM sleep without atonia (RSWA) would present with more severe and symmetric rigidity compared to individuals with PD without RSWA and age-matched controls. Methods: Sixty-one individuals participated in this study (41 PD, 20 controls). An overnight sleep study was used to classify participants with PD as having either elevated (PD-RSWA+) or normal muscle activity (PD-RSWA−) during REM sleep. Quantitative measures of rigidity were obtained using a robotic manipulandum that passively pronated and supinated the forearm. Results: Quantitative measures of forearm rigidity were significantly higher in the PD-RSWA+ group compared to the control group. Rigidity was significantly more asymmetric between limbs in the PD-RSWA− group compared with controls, while there was no significant difference in symmetry between the control and PD-RSWA+ groups. Conclusion: In people with mild to moderate PD, RSWA is associated with an increased and more symmetric presentation of upper limb rigidity. Significance: Dysfunction of brainstem systems that control muscle tone during REM sleep may contribute to increased rigidity during wakefulness in people with PD.
Bibliographical noteFunding Information:
We would like to thank our research volunteers for their participation in this study, Joshua De Kam for his role in coordinating this research, Devin O’Connell and Minwoo Kim for assistance in data collection and administration, Drs. Martha Nance, Julia Johnson, Daniel Kuyper, and Sotirios Parashos for referring volunteers to our study, and Dr. Lynn Eberly for statistical consultation. This work was supported by the National Institutes of Health grants R01 NS070264 , R01 NS088670 , P50 NS09857 , T32 GM008471 , 8UL1TR000114-02 and UL1TR000114 , National Science Foundation fellowship DGE - 1734815 , the Parkinson Study Group, the Parkinson's Disease Foundation, the Wallin Neuroscience Discovery Fund , and MnDRIVE Research Fellowships in Neuromodulation .
© 2020 International Federation of Clinical Neurophysiology
- Parkinson's disease
- REM sleep behavior disorder
- REM sleep without atonia
PubMed: MeSH publication types
- Journal Article
- Research Support, N.I.H., Extramural
- Research Support, Non-U.S. Gov't
- Research Support, U.S. Gov't, Non-P.H.S.