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Cited by 277Obstructive Sleep Apnea ResearchNeuroscience of respiration and sleepNasal Surgery and Airway Studies

Effect of nasal or oral breathing route on upper airway resistance during sleep

Open access
Fitzpatrick, M.F., McLean, H., Urton, A.M., Tan, A., O'Donnell, D., Driver, H.S.·2003·European Respiratory Journal
DOI 10.1183/09031936.03.00047903
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Abstract

Healthy subjects with normal nasal resistance breathe almost exclusively through the nose during sleep. This study tested the hypothesis that a mechanical advantage might explain this preponderance of nasal over oral breathing during sleep. A randomised, single-blind, crossover design was used to compare upper airway resistance during sleep in the nasal and oral breathing conditions in 12 (seven male) healthy subjects with normal nasal resistance, aged 30±4 (mean±sem) yrs, and with a body mass index of 23±1 kg·m 2. During wakefulness, upper airway resistance was similar between the oral and nasal breathing routes. However, during sleep (supine, stage two) upper airway resistance was much higher while breathing orally (median 12.4 cmH 2 O·L−1·s−1, range 4.5–40.2) than nasally (5.2 cmH 2 O·L−1·s−1, 1.7–10.8). In addition, obstructive (but not central) apnoeas and hypopnoeas were profoundly more frequent when breathing orally (apnoea-hypopnoea index 43±6) than nasally (1.5±0.5). Upper airway resistance during sleep and the propensity to obstructive sleep apnoea are significantly lower while breathing nasally rather than orally. This mechanical advantage may explain the preponderance of nasal breathing during sleep in normal subjects.

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Crossref · 10.1183/09031936.03.00047903

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  • Increased airway resistance from mouth breathing can narrow the pharyngeal lumen and lead to more frequent obstructive events, as shown by worsening OSA severity when mouth breathing compared to nose breathing.

    “This increased airway resistance can narrow the pharyngeal lumen leading to more frequent obstructive events, as demonstrated by Fitzpatrick et al. who found worsening of OSA severity when mouth breathing compared to nose breathing.287”

    From International Consensus Statement on Obstructive Sleep Apnea (2023) · cites this paper as [287]

    The Results report substantially more obstructive events during oral than nasal breathing, and the summary reports higher upper-airway resistance during oral breathing. The Mouth opening section describes pharyngeal narrowing as a plausible cause of the increased resistance, not an established consequence of it; the claimed causal sequence is therefore not supported. (LLM, conf=0.86)

    Experimental — accuracy not yet measured

  • Mouth breathing as a result of nasal obstruction leads to increased airway resistance.

    “Additionally, mouth breathing as a result of nasal obstruction leads to increased airway resistance [6].”

    From The Role of Isolated Nasal Surgery in Obstructive Sleep Apnea Therapy—A Systematic Review (2022) · cites this paper as [6]

    The paper’s summary reports significantly higher upper-airway resistance during oral than nasal breathing in sleep. But the Control of the oral/nasal breathing route section says no measurements established that nasal obstruction causes a switch to mouth breathing during sleep; the study tested the breathing routes rather than that causal sequence. Page numbers are unavailable in our copy. (LLM, conf=0.86)

    Experimental — accuracy not yet measured

  • Mouth breathing during sleep has been associated with up to 2.5 times higher airway resistance.

    “Mouth breathing during sleep has been associated with up to 2.5 times higher airway resistance.287”

    From International Consensus Statement on Obstructive Sleep Apnea (2023) · cites this paper as [287]

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Research works printed but not linked: 3

  1. [2]2. Rossi A, Polese G, Milic-Emili J. Monitoring respiratory mechanics in ventilator dependent patients. In: Tobin MJ, ed. Principles and practice of intensive care monitoring. New York, McGraw-Hill Inc., 1998; pp. 553-596.
  2. [38]38. Zwillich CW, Pickett C, Hanson FN, Weil JV. Disturbed sleep and prolonged apnoea during nasal obstruction in normal men. Am Rev Respir Dis 1981; 124: 158-160.
  3. [39]39. McNicholas WT, Tarlo S, Cole P, Zamel N, Rutherford R, Griffin D. Obstructive apnoeas during sleep in patients with seasonal allergic rhinitis. Am Rev Respir Dis 1982; 126: 625- 628.

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Authors
Fitzpatrick, M. F., McLean, H., Urton, A. M., Tan, A., O'Donnell, D., & Driver, H. S.
Affiliations
  • Queen's University (CA)
  • Kingston General Hospital (CA)
ORCID
Venue
European Respiratory Journal
Publisher
European Respiratory Society (ERS)
Published
2003-11
Volume
22
Issue
5
Pages
827-832
ISSN
  • 0903-1936 (ISSN-L)
  • 1399-3003
DOI
10.1183/09031936.03.00047903
OpenAlex
W2092809686
Semantic Scholar
601ec093ed8c71d859a9e57f89498025837ac4ce
Cited by
277
References
47
Citations by year
2026: 17 · 2025: 20 · 2024: 19 · 2023: 28 · 2022: 17 · 2021: 22 · 2020: 17 · 2019: 13 · 2018: 14 · 2017: 11 · 2016: 12 · 2015: 7 · 2014: 13 · 2013: 12 · 2012: 11
FWCI
2.49
Type
journal article
Language
en
Open access
Locations
  • European Respiratory Journal (publishedVersion)
  • PubMed (publishedVersion)
Topics
  • Health Sciences › Medicine › Physiology › Obstructive Sleep Apnea Research
  • Life Sciences › Neuroscience › Endocrine and Autonomic Systems › Neuroscience of respiration and sleep
  • Health Sciences › Medicine › Surgery › Nasal Surgery and Airway Studies
Keywords
upper airway resistance, nasal breathing, mouth breathing, sleep, obstructive sleep apnea, apnea-hypopnea index, mechanical advantage, nasal resistance, hypopnea
MeSH terms
Adult, Airway Resistance, Female, Humans, Male, Mouth Breathing, Nose, Sleep, Wakefulness, Single-Blind Method, Cross-Over Studies, Sleep Apnea, Obstructive

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