Effects of Auto-Titrating Mandibular Advancement Device on Autonomic Nervous System in Obstructive Sleep Apnea

<b>Background/Objectives:</b> One prior study revealed that a newly developed auto-titrating mandibular advancement device (AMAD) could potentially enhance polysomnographic outcomes in individuals with obstructive sleep apnea (OSA). However, evidence regarding its impact on autonomic nervous system dysregulation in OSA remains limited. In this study, we aimed to compare the effects of conventional mandibular advancement devices (MADs) and AMDA on autonomic function. <b>Methods</b>: We retrospectively reviewed data from patients who visited a sleep center with complaints of snoring and sleep apnea (30 and 15 patients in the conventional MAD and AMAD groups, respectively). We assessed heart rate variability (HRV) frequency-domain metrics such as total power (TP), very low frequency (VLF), low frequency (LF), and high frequency (HF) using ultra-short-term and short-term modalities, assessing sympathetic and parasympathetic activity changes across treatment groups. <b>Results</b>: Conventional MAD treatment was associated with reductions in LF and LF/HF ratios, whereas AMAD treatment was linked to decreases in TP, VLF, LF, and LF/HF ratios. Notably, in patients with moderate OSA, LF values were significantly lower in the AMAD group than in the conventional MAD group. <b>Conclusions</b>: These findings suggest that both devices could reduce sympathetic over-activity in patients with OSA, with AMAD demonstrating greater efficacy, particularly in those with moderate OSA.