Abstract Introduction Obstructive sleep apnea (OSA) is characterized by recurrent upper airway collapse and sleep fragmentation. A low respiratory arousal threshold (AT), defined as awakening easily to respiratory events, contributes to poor sleep quality and reduced adherence to OSA therapies. AT can be estimated from sleep studies, but it influences patient symptoms remains unexplored. Our aim was to identify symptoms related to low AT. Methods From consecutive new patients presenting to an otolaryngology sleep clinic, we collected a standardized questionnaire that combined a sleep history with Epworth Sleepiness Scale (ESS), Insomnia Severity Index (ISI), Nasal Obstruction Symptom Evaluation (NOSE). Our inclusion criteria were adult patients who completed this questionnaire and a home sleep study (HST) between 12/1/24-3/31/25. Patients without OSA were excluded. Patients were categorized as low AT or high AT based on their HST report using a validated screening tool that assigns one point for: AHI 30, nadir oxygen saturation82.5%, and hypopneas comprising 58.3% of respiratory events. A total score ≥2 indicates low AT. Group differences in questionnaire scores were evaluated using Wilcoxon rank sum and chi-square tests. Logistic regression models were constructed to identify independent predictors of low AT. Results 129 patients were included. In univariate analyses, low AT was significantly associated with longer subjective sleep latency (median 20.0 min vs 13.8 min; p=0.041), higher ISI scores reflecting worry or distress about sleep difficulties (Question #6; median 2.5 vs 2.0; p=0.044), and lower ESS scores for sitting inactive in a public place (Question #3; 0.0 vs median 1.0; p=0.029). In multivariable regression adjusting for AHI, ISI Q6 and ESS remained independent predictors of low AT. Upon adjustment, NOSE scores for nasal obstruction were also found to be significantly associated with low AT (Question #2; OR 1.08, 95% CI 1.00–1.16, p=0.041). Conclusion Within our cohort, patients with a low AT were more likely to report distinct symptoms: longer subjective sleep latency, more worry about sleep, and greater nasal congestion. These findings suggest that symptom-based screening may help identify patients with OSA who have a low AT. Support (if any) University of Pittsburgh T32 Training Grant in Sleep and Circadian Science
Stachula et al. (Fri,) studied this question.