Night-to-Night Variability of Novel Physiological Parameters in Home Sleep Apnea Testing

Insel Gruppe AG, University Hospital Bern192 enrolled

Overview

Obstructive sleep apnea (OSA) is usually diagnosed from a single night of home sleep apnea testing using the apnea-hypopnea index (AHI). However, the AHI varies substantially from night to night, undermining diagnostic accuracy, and shows only modest correlation with symptoms. This variability further limits its usefulness for predicting cardiovascular and other complications. Besides the traditional AHI, more robust physiological markers are needed. Several emerging physiological metrics - hypoxic burden, ventilatory burden, heart rate variability, autonomic arousals, and the pulse wave amplitude drop index - capture the physiological impact of OSA more comprehensively and demonstrate stronger associations with cardiovascular risk. Despite this promise, their night-to-night variability has not been studied. A systematic evaluation of both established and novel OSA metrics across nights is essential to identify reliable, stable parameters suitable for clinical routine. This improves diagnostic precision beyond what traditional metrics can provide, enhances patient selection, reduces costs and patient harm, and may improve treatment outcomes.

Study Type

OBSERVATIONAL

Enrollment

192

Conditions

Obstructive Apnea Diagnostic Sleep Apnea Syndrome (OSAS)

Eligibility

Sex: ALLMin age: 18 Years

Medical Language ↔ Plain English

Inclusion Criteria: * Patients with suspected or diagnosed sleep-disordered breathing, irrespective of disease severity, as defined by the indications for home sleep apnea testing in the German guidelines \[15\] * No active treatment during sleep recordings or within preceding two weeks (e.g., mandibular advancement devices, positive airway pressure therapy) * Written informed consent obtained Exclusion Criteria: * Age \<18 years * Known or suspected neurological sleep disorder (e.g., narcolepsy, parasomnia) * Known or suspected psychiatric sleep disorder * Known or suspected central and complex sleep apnea * Participants who are unable to perform sleep measurements reliably * Insufficient knowledge of the project language (German) * Inability to give consent * Shift workers (with shift work \<2 weeks before testing)

Outcomes

Primary Outcomes

Night-to-night variability of apnea-hypopnea index (events per hour of sleep) over 4 nights

The variability of the apnea-hypopnea index (events per hour of sleep) over 4 nights will be quantified using linear mixed-effects models, accounting for confounding variables.

Time frame: 4 nights of respiratory polygraphy

Night-to-night variability of oxygen desaturation index (events per hour of sleep) over 10 nights

The variability will be quantified using linear mixed-effects models, accounting for confounding variables.