The Effect of Mandibular Advancement Devices on Sympathetic Nerve Activity and Markers of Cardiovascular Health in Obstructive Sleep Apnea Patients: A Prospective Case Series Protocol

Study Objectives:The effect of mandibular advancement devices (MADs) on sympathetic nerve activity (SNA) has not been measured directly through microneurography.Therefore, this protocol aims to determine whether MADs improve SNA, vascular health, blood pressure, and indirect markers of SNA (heart rate variability and concentrations of neurotransmitters in the blood) in adult study participants with OSA.Methods: Patients with a diagnosis of OSA will be referred by multiple dental practitioners in Edmonton, Alberta who are certified to provide MAD therapy.A sample size of 50 participants is planned, considering a 20% dropout rate.Participants will be examined at baseline and again after 3 and 6 months of efficacious MAD therapy.The following outcomes will be recorded at each time point: direct SNA via microneurography, heart rate, continuous blood pressure, flow-mediated dilation (a marker of vascular health), blood concentration of noradrenaline, apnea-hypopnea index (AHI) via a level 3 take-home sleep study, and MAD compliance via a scorecard for self-reported nighttime wear.Clinical Implications: Understanding how direct and indirect measures of SNA relate to OSA therapy may be valuable, as some participants and researchers consider microneurography an invasive and complex technique.Improved SNA and vascular health would further support MADs as an important alternative to no treatment.Finally, research examining the effect of various OSA therapies on the sympathetic influence of blood pressure and the heart is critical to understanding how changes in cardiac autonomic modulation may influence cardiovascular risk.