ArticleSleep2016
Upper Airway Collapsibility (Pcrit) and Pharyngeal Dilator Muscle Activity are Sleep Stage Dependent.
Article in Sleep, 2016. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 80 papers, 3 of them syntheses that pooled it.
What it found
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
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Who cites it
80 citing papers in PubMed, 3 syntheses or guidelines pooled it, 158 citations in OpenAlex.
- Association between obstructive sleep apnea and multiple adverse clinical outcomes: evidence from an umbrella review.Frontiers in medicine · 2025Pooled it
- Myofunctional therapy (oropharyngeal exercises) for obstructive sleep apnoea.The Cochrane database of systematic reviews · 2020Pooled it
- Associations of variants In the hexokinase 1 and interleukin 18 receptor regions with oxyhemoglobin saturation during sleep.PLoS genetics · 2019Pooled it
- BAY 2253651 for the treatment of obstructive sleep apnoea: a multicentre, double-blind, randomised controlled trial (SANDMAN).The European respiratory journal · 2021Trial
- Efficacy of a novel oral appliance and the role of posture on nasal resistance in obstructive sleep apnea.Journal of clinical sleep medicine : JCSM : official publication of the American Academy of Sleep Medicine · 2020Trial
- Effects of Tiagabine on Slow Wave Sleep and Arousal Threshold in Patients With Obstructive Sleep Apnea.Sleep · 2017Trial
- Trial
- Preoperative video laryngoscopic examination for difficult intubation in obese patients.Die Anaesthesiologie · 2026Article
- Article
- Epithelial NaJournal of sleep research · 2026Article
- OSA Endotyping as Targets for Treatment. How Far Have We Come?Respirology (Carlton, Vic.) · 2026Review
- The upper airway in obstructive sleep apnoea: state of the art.European respiratory review : an official journal of the European Respiratory Society · 2026Review
- Review
- Glossopharyngeal airway collapse is the main factor leading REM-related oxygen desaturation in patients with obstructive sleep apnea: a pilot study.Sleep & breathing = Schlaf & Atmung · 2026Article
- Management of Adult Obstructive Sleep Apnoea: Many Questions, Not Enough Answers!Journal of sleep research · 2025Review
- Oxygen regulated protein 150 can be considered as a severity indicator in obstructive sleep apnea.Scientific reports · 2025Article
- General Dentists and Dental Specialists' Knowledge of Treatment, Diagnosis, Referral, and Risk Factors of Obstructive Sleep Apnea: A Systematic Review.Dentistry journal · 2025Review
- Prevalence and Risk Factors of Positional Obstructive Sleep Apnea in Chinese Children: A Retrospective Study.Nature and science of sleep · 2025Article
- The impact of obesity on upper airway anatomy as assessed by magnetic resonance imaging and obstructive sleep apnea endotypic traits.Frontiers in physiology · 2025Article
- Endotypic Trait Differences in Class 2/3 Obese Patients with and without Obstructive Sleep Apnea: A Preliminary Analysis of Preoperative Bariatric Surgery Patients.Annals of the American Thoracic Society · 2024Article
20 more citing papers are in PubMed but not listed here.
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
5 authors at 4 institutions in 2 countries.
Funding
Abstract
STUDY
objectivesAn anatomically narrow/highly collapsible upper airway is the main cause of obstructive sleep apnea (OSA). Upper airway muscle activity contributes to airway patency and, like apnea severity, can be sleep stage dependent. Conversely, existing data derived from a small number of participants suggest that upper airway collapsibility, measured by the passive pharyngeal critical closing pressure (Pcrit) technique, is not sleep stage dependent. This study aimed to determine the effect of sleep stage on Pcrit and upper airway muscle activity in a larger cohort than previously tested.
methodsPcrit and/or muscle data were obtained from 72 adults aged 20-64 y with and without OSA.Pcrit was determined via transient reductions in continuous positive airway pressure (CPAP) during N2, slow wave sleep (SWS) and rapid eye movement (REM) sleep. Genioglossus and tensor palatini muscle activities were measured: (1) awake with and without CPAP, (2) during stable sleep on CPAP, and (3) in response to the CPAP reductions used to quantify Pcrit.
resultsPcrit was 4.9 ± 1.4 cmH2O higher (more collapsible) during REM versus SWS (P = 0.012), 2.3 ± 0.6 cmH2O higher during REM versus N2 (P < 0.001), and 1.6 ± 0.7 cmH2O higher in N2 versus SWS (P = 0.048). Muscle activity decreased from wakefulness to sleep and from SWS to N2 to REM sleep for genioglossus but not for tensor palatini. Pharyngeal muscle activity increased by ∼50% by breath 5 following CPAP reductions.
conclusionsUpper airway collapsibility measured via the Pcrit technique and genioglossus muscle activity vary with sleep stage. These findings should be taken into account when performing and interpreting "passive" Pcrit measurements.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.