Positive airway pressure level based upper airway collapsibility classification – the European Sleep Apnea Database (ESADA)

Background and objectives: Obstructive sleep apnea (OSA) patients with mild upper airway collapsibility represents a target group for potential non-positive airway pressure (PAP) treatment. We studied the clinical characteristics of this endotypic group in a large Pan-European sleep apnea registry. Methods: A retrospective analysis was performed in 2541 OSA patients with fixed PAP treatment (male 74%, age 53±11 years, body mass index [BMI] 33±6 kg/m2, apnea-hypopnea index [AHI] 41±25 events/h at baseline). Therapeutic PAP level ≤8 cm H2O was used as the cut-off to classify patients with mild upper airway collapsibility (Landry SA et al. Sleep 2017; 40:6). Results: Mean pressure of the PAP therapy was 9±2 cm H2O and treatment compliance was 5.1±2.1 h/day. A total of 39% of patients had a PAP level ≤8 cm H2O. In a multivariate logistic regression model, compared to patients with PAP >8 cm H2O, hyperlipidemia was more prevalent in mild airway collapsibility patients (OR [95%CI] 1.23 [1.00-1.51], p=0.047). BMI, waist-to-hip ratio, neck circumference, AHI and diagnosis of hypertension were negatively associated with the mild collapsibility group (0.97 [0.95-0.99], 0.26 [0.10-0.64], 0.96 [0.93-1.00], 0.99 [0.98-0.99], 0.75 [0.61-0.92], p=0.006, 0.003, 0.034, Conclusion: Body composition, comorbidities and OSA severity predicted mild upper airway collapsibility defined by therapeutic PAP level in the ESADA cohort. PAP-based phenotyping approach may provide a simple tool for personalized medicine in OSA.