In reference to snoring and carotid artery intima‐media thickness

We read with great interest the recent article by Deeb et al. regarding the relationship that exists between snoring and intima-media thickness (IMT) of the carotid arteries. The authors very clearly discussed the relationship between primary snoring and IMT of the carotid arteries. They concluded that the relationship between increased carotid IMT and serious health conditions, and nonapneic snoring may be a precursor to changes of the carotid artery. In addition to their fluent discussion, we aim to emphasize the possible other effective mechanism of snoring and carotid artery IMT: the contribution of autonomic nervous system function. Previous studies clearly showed that obstructive sleep apnea syndrome (OSAS) and snoring lead to nocturnal intermittent hypoxia, increased negative intrathoracic pressure, increased sympathetic nervous system activity, and elevation of reactive oxygen radicals. All of these factors cause vascular atherosclerosis. Previously, we showed that a close relationship between OSAS and impaired autonomic nervous system function is detected by different methods in OSAS patients without coronary artery diseases or other comorbidities. Together with this, nocturnal intermittent hypoxiarelated impairment in autonomic nervous system function is thought to play a central role in the risk of cardiovascular death. Several studies in the literature showed that IMT of the carotid artery and impaired cardiac autonomic function are inversely related. Galetta et al. clearly illustrated the relationship between the imbalance of cardiac autonomic activity and the development of carotid artery IMT. They discussed that the imbalance of cardiac autonomic activity plays an important role in the development of atherosclerosis through three possible mechanisms: increased heart rate with a consequent increase in oxygen consumption, increased shear stress leading to plaque fissure, and enhanced atherosclerosis through increased macrophage low-density lipoprotein cholesterol oxidation. We believe that the effect of snoring and IMT on autonomic nervous system function may play a role in the results described in article by Deeb et al. We hope that the above-mentioned items will add to the value of their well-written article regarding the relationship that exists between snoring and IMT of the carotid arteries.