Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2021 May 1;17(5):957-963.
doi: 10.5664/jcsm.9074.

Reduced sympatho-vagal responses to orthostatic stress in drug-naïve idiopathic restless legs syndrome

Jung-Won Shin  1 , Jun-Sang Sunwoo  2 , Jung-Ick Byun  3 , Tae-Joon Kim  4 , Jin-Sun Jun  5 , Won Chan Kim  1 , Ki-Young Jung  6
Affiliations

Reduced sympatho-vagal responses to orthostatic stress in drug-naïve idiopathic restless legs syndrome

Jung-Won Shin et al. J Clin Sleep Med. .

Abstract

Study objectives: Restless legs syndrome (RLS) is known to be a risk factor for cardiovascular disease. However, there are no electrophysiological biomarkers to assess this risk. This study aimed to evaluate heart rate variability (HRV) and cardiovascular reflexes in the supine and standing positions during wakefulness in patients with RLS.

Methods: Fourteen drug-naïve patients with RLS (12 women and 2 men, mean age, 42.14 ± 7.81 years) and 10 healthy control patients underwent tests for blood pressure, heart rate when in the supine and standing positions, and deep breathing and handgrip tests in controlled laboratory conditions. Data on 5-minute R-R intervals at each position were collected and analyzed for HRV.

Results: Expected cardiovascular reflexes were within the normal range and were similar between the 2 groups. In HRV analysis, the normalized unit of the low-frequency component and the low-frequency/high-frequency ratio during standing were lower in patients with RLS than in the control patients. The low-frequency/high-frequency ratio responses during the change from the supine to the standing position were significantly reduced in patients with RLS (mean ± standard deviation, 2.94 ± 3.11; control patients: 7.51 ± 5.58; P = .042.) On Spearman rank correlation, questionnaires related to sleep problems were associated with the parameters of HRV.

Conclusions: Patients with RLS showed reduced sympatho-vagal responses during the change from the supine to the upright position during wakefulness, and RLS-related sleep disturbance was a contributing factor for autonomic nervous system dysfunction. This case-control study showed a difference in HRV response to position change in a considerably small group of patients with RLS. The relevance of this finding is uncertain, but it may be worthy of further investigation in longitudinal studies on RLS and cardiovascular disease.

Keywords: cardiovascular disease; heart rate variability; restless legs syndrome.

PubMed Disclaimer

Conflict of interest statement

All of the authors have seen and approved the manuscript. Work for this study was supported by a National Research Foundation of Korea, South Korea grant funded by the Korean government (number NRF-2017R1D1A1B03029293) and performed at the authors’ respective institutions. The authors report no conflicts of interest.

Figures

Figure 1
Figure 1. LF and HF normalized units and LF/HF ratio in supine and standing position in patients with RLS and control patients.
Values are mean ± standard deviation. *P < .05. The Mann-Whitney U test was used to compare variables between the groups. HFn = high-frequency normalized units (HF/total power-very low frequency) × 100, LFn = low-frequency normalized units (LF/total power-very low frequency) × 100.
See this image and copyright information in PMC

References

    1. Allen RP, Picchietti DL, Garcia-Borreguero D, et al. . Restless legs syndrome/Willis-Ekbom disease diagnostic criteria: updated International Restless Legs Syndrome Study Group (IRLSSG) consensus criteria—history, rationale, description, and significance. Sleep Med. 2014;15(8):860–873. 10.1016/j.sleep.2014.03.025 - DOI - PubMed
    1. Gottlieb DJ, Somers VK, Punjabi NM, Winkelman JW. Restless legs syndrome and cardiovascular disease: a research roadmap. Sleep Med. 2017;31:10–17. 10.1016/j.sleep.2016.08.008 - DOI - PMC - PubMed
    1. Chenini S, Rassu AL, Guiraud L, et al. . Blood pressure profile and endothelial function in restless legs syndrome. Sci Rep. 2019;9:15933. 10.1038/s41598-019-52401-4 - DOI - PMC - PubMed
    1. Rassu AL, Chenini S, Barateau L, et al. . Increased blood pressure during the suggested immobilization test in restless legs syndrome. Sleep. 2020;43(4):zsz263. 10.1093/sleep/zsz263 - DOI - PubMed
    1. Sieminski M, Partinen M. Nocturnal systolic blood pressure is increased in restless legs syndrome. Sleep Breath. 2016;20(3):1013–1019. 10.1007/s11325-016-1333-0 - DOI - PMC - PubMed

Publication types

Substances