
School of Medicine Publications and Presentations
Document Type
Article
Publication Date
10-2019
Abstract
Background
Decreased short-interval intracortical inhibition (SICI) to transcranial magnetic stimulation (TMS) of the primary motor cortexwas described in subjects with restless legs syndrome/Willis-Ekbom disease (RLS/WED). It remained to be determined whether the magnitude of SICI decrease would be similar across levels of RLS/WED severity. Moreover, it was unknown whether, in addition to decreases in SICI, changes in cortical thickness or area could be detected in subjects with RLS/WED compared to controls. The objective of this study was to compare SICI, cortical thickness, and cortical area in subjects with idiopathic mild to moderate RLS/WED, severe to very severe RLS/WED, and controls.
Methods
The severity of RLS/WED was assessed by the International Restless Legs Syndrome Severity Scale (IRLSS). SICI and 3T magnetic resonance imaging (MRI) data of subjects with RLS/WED and controls were compared. A receiver operating characteristic curve for SICI was designed for discrimination of participants with RLS/WED from controls. Cortical thickness and area were assessed by automated surface-based analysis.
Results
SICI was significantly reduced in patients with mild to moderate and severe to very severe RLS/WED, compared to controls (one-way analysis of variance: F = 9.62, p < 0.001). Receiver operating characteristic curve analysis predicted RLS/WED when SICI was above 35% (area under the curve = 0.79, 95% CI 0.67–0.91, p< 0.001). Analyses of the whole brain and of regions of interest did not reveal differences in gray matter thickness or area between controls and subjects with RLS/WED.
Conclusion
SICI is an accurate cortical biomarker that can support the diagnosis of RLS/WED even in subjects with mild symptoms, but cortical thickness and area were not useful for discriminating subjects with this condition from controls.
Recommended Citation
Magalhães, S. C., de Paiva, J. P. Q., Kaelin-Lang, A., Sterr, A., Eckeli, A. L., Winkler, A. M., ... & Conforto, A. B. (2019). Short-interval intracortical inhibition is decreased in restless legs syndrome across a range of severity. Sleep medicine, 62, 34-42. https://doi.org/10.1016/j.sleep.2019.03.021
Creative Commons License
This work is licensed under a Creative Commons Attribution-NonCommercial-No Derivative Works 4.0 International License.
Publication Title
Sleep Medicine
DOI
https://doi.org/10.1016/j.sleep.2019.03.021
Academic Level
faculty
Mentor/PI Department
Office of Human Genetics
Comments
Original published version available at https://doi.org/10.1016/j.sleep.2019.03.021