Nature and Science of Sleep (Apr 2022)
Mandibular Movements are a Reliable Noninvasive Alternative to Esophageal Pressure for Measuring Respiratory Effort in Patients with Sleep Apnea Syndrome
Abstract
Jean-Louis Pepin,1,* Nhat-Nam Le-Dong,2,* Valérie Cuthbert,3 Nathalie Coumans,3 Renaud Tamisier,1 Atul Malhotra,4 Jean-Benoit Martinot3,5 1HP2 Laboratory, Inserm U1300, University Grenoble Alpes, Grenoble, France; 2Sunrise, Namur, Belgium; 3Sleep Laboratory, CHU Université Catholique de Louvain (UCL) Namur Site Sainte-Elisabeth, Namur, Belgium; 4University of California San Diego, La Jolla, CA, USA; 5Institute of Experimental and Clinical Research, UCL Bruxelles Woluwe, Brussels, Belgium*These authors contributed equally to this workCorrespondence: Jean-Benoit Martinot, Centre du Sommeil et de la Vigilance, CHU-UCL Namur Site Ste Elisabeth, 15 Place Louise Godin, Namur, 5000, Belgium, Tel +32 495502608, Fax +32 81570754, Email [email protected]: Differentiation between obstructive and central apneas and hypopneas requires quantitative measurement of respiratory effort (RE) using esophageal pressure (PES), which is rarely implemented. This study investigated whether the sleep mandibular movements (MM) signal recorded with a tri-axial gyroscopic chin sensor (Sunrise, Namur, Belgium) is a reliable surrogate of PES in patients with suspected obstructive sleep apnea (OSA).Patients and Methods: In-laboratory polysomnography (PSG) with PES and concurrent MM monitoring was performed. PSGs were scored manually using AASM 2012 rules. Data blocks (n=8042) were randomly sampled during normal breathing (NB), obstructive or central apnea/hypopnea (OA/OH/CA/CH), respiratory effort-related arousal (RERA), and mixed apnea (MxA). Analyses were evaluation of the similarity and linear correlation between PES and MM using the longest common subsequence (LCSS) algorithm and Pearson’s coefficient; description of signal amplitudes; estimation of the marginal effect for crossing from NB to a respiratory disturbance for a given change in MM signal using a mixed linear-regression.Results: Participants (n=38) had mild to severe OSA (median AH index 28.9/h; median arousal index 23.2/h). MM showed a high level of synchronization with concurrent PES signals. Distribution of MM amplitude differed significantly between event types: median (95% confidence interval) values of 0.60 (0.16– 2.43) for CA, 0.83 (0.23– 4.71) for CH, 1.93 (0.46– 12.43) for MxA, 3.23 (0.72– 18.09) for OH, and 6.42 (0.88– 26.81) for OA. Mixed regression indicated that crossing from NB to central events would decrease MM signal amplitude by – 1.23 (CH) and – 2.04 (CA) units, while obstructive events would increase MM amplitude by +3.27 (OH) and +6.79 (OA) units (all p< 10− 6).Conclusion: In OSA patients, MM signals facilitated the measurement of specific levels of RE associated with obstructive, central or mixed apneas and/or hypopneas. A high degree of similarity was observed with the PES gold-standard signal.Keywords: obstructive sleep apnea, respiratory effort, mandibular movements, esophageal pressure