Heart rate changes associated with rhythmic masticatory muscle activities and limb movements in sleep bruxers: Preliminary findings

ABSTRACT

Objective: To investigate the relationship of rhythmic masticatory muscle activities (RMMAs) and limb movements (LMs) with heart rate (HR) acceleration.

Methods: The amplitude and duration of HR increases, the time to reach peak HR associated with RMMAs/LMs during sleep, duration of movement events, and their relationships with cortical arousal levels were determined in 9 sleep bruxers and 10 normal controls.

Results: A total of 48.15% and 49.44% HR increased before the onset of RMMAs/LMs in the sleep bruxers and controls, respectively. All of the parameters of HR increases were significantly different between the sleep bruxers and the controls (p < 0.05–0.001) and between different cortical arousal levels (p < 0.01), and the duration of RMMAs/LMs was positively correlated with the parameters (Sleep bruxers: r² = 0.18–0.88, p < 0.0001; Controls: r² = 0.16–0.78, p < 0.0001).

Discussion: These data suggest the HR increases are associated with the movement events and changes in cortical arousal levels in the sleep bruxers and controls.

Abbreviations: LMs: Limb movements; HR: Heart rate; RMMAs: Rhythmic masticatory muscle activities; SB: Sleep bruxism; PSG: Polysomnographic; EEG: Electroencephalographic; PLMS: Periodic leg movements; SSRIs: Selective serotonin reuptake inhibitors; ECG: Electrocardiographic; EOG: Electrooculographic; EMG: Electromyographic; SD: Standard deviation; Fig: Figure; SEM: Standard error of mean; N1: Non-rapid eye movement sleep stage 1; N2: Non-rapid eye movement sleep stage 2; N3: Non-rapid eye movement sleep stage 3; REM: Rapid eye movement ; NA: No arousal; mAR: Microarousal; AW: Awakening

KEYWORDS:

• Sleep bruxism
• jaw movements
• limb movements
• heart rate
• cortical arousals

Acknowledgments

The authors are grateful to the volunteers for participating in the experiments.

Disclosure statement

The authors have no financial conflicts of interest in relation to this paper. The study did not involve off-label or investigational use of any medication.

Geolocation information

The study was performed at the Jiangxi Mental Hospital in China.

Additional information

Funding

This study was supported by Jiangxi Natural Scientific Grant (Projects for Young Scholars) 2014BAB215070, Jiangxi Natural Scientific Grant S2017ZRMSB2145 and National Natural Scientific Grant of China 81760202]