Cardiac autonomic control in the obstructive sleep apnea

Abstract

IntroductionThe sympathetic activation is considered to be the main mechanism involved in the development of cardiovascular diseases in obstructive sleep apnea (OSA). The heart rate variability (HRV) analysis represents a non-invasive tool allowing the study of the autonomic nervous system. The impairment of HRV parameters in OSA has been documented. However, only a few studies tackled the dynamics of the autonomic nervous system during sleep in patients having OSA.AimsTo analyze the HRV over sleep stages and across sleep periods in order to clarify the impact of OSA on cardiac autonomic modulation. The second objective is to examine the nocturnal HRV of OSA patients to find out which HRV parameter is the best to reflect the symptoms severity.MethodsThe study was retrospective. We have included 30 patients undergoing overnight polysomnography. Subjects were categorized into two groups according to apnea–hypopnea index (AHI): mild-to-moderate OSAS group (AHI: 5–30) and severe OSAS group (AHI>30). The HRV measures for participants with low apnea–hypopnea indices were compared to those of patients with high rates of apnea–hypopnea across the sleep period and sleep stages.ResultsHRV measures during sleep stages for the group with low rates of apnea–hypopnea have indicated a parasympathetic activation during non-rapid eye movement (NREM) sleep. However, no significant difference has been observed in the high AHI group except for the mean of RR intervals (mean RR). The parasympathetic activity tended to increase across the night but without a statistical difference. After control of age and body mass index, the most significant correlation found was for the mean RR (p=0.0001, r=−0.248).ConclusionOSA affects sympathovagal modulation during sleep, and this impact has been correlated to the severity of the disease. The mean RR seemed to be a better index allowing the sympathovagal balance appreciation during the night in OSA.

Use of Mutual Information and Transfer Entropy to Assess Interaction between Parasympathetic and Sympathetic Activities of Nervous System from HRV

“…This conclusion is supported by other literatures. They found that the more serious OSA patient was, the more variability the HRV decreased [5,15,17]. It is known that sympathetic system and parasympathetic system are two antagonistic parts of ANS.…”

“…It supports the view that the information representation of 1-min epoch is the same as 5 or more-min epoch. The work by Gammoudi et al [15] compared the 5-min epoch of RR-intervals (RRI) during free-events to those with obstructive events and found that there were no significant differences in LF/HF, LFnu and HFnu. The possible reason is that it is too long for 5-min epoch to analyze the distinction between patients during normal breathing and obstructive events.…”

“…Most of HRV studies are focused on the changes of features which reflect sympathetic and parasympathetic activity of ANS [13][14][15]. Gong et al [16] used 25 OSA patients and 27 normal participants and found that the LF/HF and normalized LF (nuLF) were significantly associated with the value of AHI.…”

Sleep restriction progress to cardiac autonomic imbalance

“…9 The sympathetic activation is considered to be the main mechanism involved in the development of cardiovascular diseases in sleep impairment. 12,13 The impairment of HRV parameters with an increased incidence of adverse cardiovascular and metabolic disorders in sleep loss has been acknowledged. [14][15][16] However, only limited studies have conveyed upon the dynamics of the autonomic nervous system during partial sleep loss or restricted sleep.…”

Usefulness of cardiac parasympathetic index in CPAP‐treated patients with obstructive sleep apnea: A preliminary study

“…Heart rate variability (HRV) analysis has been considered for several years to be a simple and non-invasive tool for investigating the cardiac autonomic system (Task Force of the European Society of Cardiology the North American Society of Pacing Electrophysiology, 1996). There are well-documented evidences on short-and long-term HRV analysis in patients with OSA (Aydin et al, 2004;Gammoudi, Cheikn, Saafi, Sakly, & Dogui, 2015;Gong et al, 2016;Noda, Yasuma, Okada, & Yokota, 1998;Park et al, 2008). In this context, the cardiac autonomic indexes, recently described as HRV-derived measurements, have been proven to accurately identify patients with sleep disorders including OSA and rapid eye movement (REM) sleep behaviour disorder (RBD; Salsone et al, 2016Salsone et al, , 2018.…”