Effects of Continuous Positive Airway Pressure Treatment on Sawtooth Waves During Rapid Eye Movement Sleep in Obstructive Sleep Apnea Patients

Yuhao Mao; Qi Li; Xueliang Zou; Zhijun Zhong; Qian Ouyang; Chunmei Gan; Fang Yi; Yaxing Luo; Zilin Cheng; Dongyuan Yao

doi:10.2147/NSS.S489288

Effects of Continuous Positive Airway Pressure Treatment on Sawtooth Waves During Rapid Eye Movement Sleep in Obstructive Sleep Apnea Patients

Nat Sci Sleep. 2024 Dec 17:16:2111-2124. doi: 10.2147/NSS.S489288. eCollection 2024.

Authors

Yuhao Mao^#^{1

2}, Qi Li^#¹, Xueliang Zou³, Zhijun Zhong¹, Qian Ouyang¹, Chunmei Gan¹, Fang Yi¹, Yaxing Luo¹, Zilin Cheng^{1

2}, Dongyuan Yao¹

Affiliations

¹ Neurological Institute of Jiangxi Province and Department of Neurology, Jiangxi Provincial People's Hospital, The First Affiliated Hospital of Nanchang Medical College, and Xiangya Hospital of Central South University at Jiangxi, Nanchang, Jiangxi, People's Republic of China.
² Queen Mary College, Nanchang University, Jiangxi, People's Republic of China.
³ Jiangxi Mental Hospital, Nanchang University, Jiangxi, People's Republic of China.

^# Contributed equally.

Abstract

Background: Obstructive sleep apnea (OSA) is the most common sleep-related breathing disorder characterized by recurrent upper airway collapse and obstruction, leading to reduced or absent breathing during sleep, especially rapid eye movement (REM) sleep, and continuous positive airway pressure treatment (CPAP) is often used for treatment of OSA. Sawtooth waves (STWs) are a characteristic of REM sleep.

Objective: To examine effects of CPAP treatment on STWs during REM sleep in the OSA patients.

Methods: Polysomnographic recordings were performed on 20 moderate-to-severe OSA patients and 16 normal controls, and comparisons of STWs during REM sleep in the OSA patients with and without CPAP treatment (paired t-test or Wilcoxon signed-rank test wherever appropriate), and between OSA patients and normal controls (Student's t-test or Wilcoxon rank-sum test) were carried out. In addition, linear correlation analyses were used to estimate the relationship of STWs and REM sleep with duration of non-REM (NREM) sleep stage 3 (N3).

Results: The STWs were classified to be apnea/hypopnea associated and not associated (isolated), and the amplitude of the isolated STWs was significantly higher than that of the apnea/hypopnea associated. With CPAP treatment, the percentage of REM sleep with STWs and the amplitude of STWs were significantly increased to the levels, which were not significantly different from those in the normal controls, while the frequency of STWs was not significantly changed. In addition, the total duration of REM sleep and the duration of REM sleep with STWs were both positively correlated with the duration of N3 sleep in the normal controls and the OSA patients with CPAP treatment. Furthermore, CPAP treatment also caused a significant increase in the duration of rapid eye movements in REM sleep.

Conclusion: These findings suggest that there are some interconnections between NREM and REM sleep, and STWs not only represent the quality of REM sleep but also are correlated with N3 sleep.

Keywords: continuous positive airway pressure; non-rapid eye movement sleep; obstructive sleep apnea; rapid eye movement sleep; sawtooth wave.

Grants and funding

This research was supported by the Jiangxi Provincial People’s Hospital Grant 2019-009, Jiangxi Provincial Overseas High-level Talent Project (No. 20242BCE50018) and Jiangxi Province Key Laboratory of Neurology Grant (No. 2024SSY06081).