Relationship Between Upper Airway Collapsibility (Pcrit) And Pharyngeal Structures

Kim, Christopher; Jackson, Nicholas; Marcus, Carole L.; Pien, Grace W.; Staley, Beth; Sun, Yi; Wieland, William; Schwab, Richard J.

doi:10.1164/ajrccm-conference.2012.185.1_meetingabstracts.a2430

Cited by 1 publication

(2 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Compared with patients with OSA, weight-matched individuals without apnea tend to have reduced fat distribution to the neck (23), and at a local pharyngeal level exhibit reduced tongue fat (8) and parapharyngeal fat pad volumes (5-8, 24, 25). Overweight/obese individuals without apnea also have craniofacial features that provide a greater anatomic reserve for fat deposition by increased intramandibular volume (7,26,27). These advantageous structural differences are likely under genetic control given the familial nature of upper-airway structure and OSA (28)(29)(30)(31).…”

Section: Mechanisms Of Advantageous Physiology In Overweight and Obesmentioning

confidence: 99%

See 1 more Smart Citation

Enhanced Upper-Airway Muscle Responsiveness Is a Distinct Feature of Overweight/Obese Individuals without Sleep Apnea

Sands

Eckert

Jordan

et al. 2014

Am J Respir Crit Care Med

Self Cite

116

View full text Add to dashboard Cite

Rationale: Body habitus is a major determinant of obstructive sleep apnea (OSA). However, many individuals do not have OSA despite being overweight/obese (body mass index . 25 kg/m 2 ) for reasons that are not fully elucidated.Objectives: To determine the key physiologic traits (upper-airway anatomy/collapsibility, upper-airway muscle responsiveness, chemoreflex control of ventilation, arousability from sleep) responsible for the absence of OSA in overweight/obese individuals.Methods: We compared key physiologic traits in 18 overweight/ obese subjects without apnea (apnea-hypopnea index , 15 events per hour) with 25 overweight/obese matched patients with OSA (apnea-hypopnea index > 15 events per hour) and 11 normal-weight nonapneic control subjects. Traits were measured by repeatedly lowering continuous positive airway pressure to subtherapeutic levels for 3 minutes during non-REM sleep.Measurements and Main Results: Overweight/obese subjects without apnea exhibited a less collapsible airway than overweight/ obese patients with apnea (critical closing pressure: 23.7 6 1.9 vs. 0.6 6 1.2 cm H 2 O; P = 0.003; mean 6 95% confidence interval), but a more collapsible airway relative to normal-weight control subjects (28.8 6 3.1 cm H 2 O; P , 0.001). Notably, overweight/obese subjects without apnea exhibited a threefold greater upper-airway muscle responsiveness than both overweight/obese patients with apnea (Dgenioglossus EMG/Depiglottic pressure: 20.49 [20.22 to 20.79] vs. 20.15 [20.09 to 20.22] %max/cm H 2 O; P = 0.008; mean [95% confidence interval]) and normal-weight control subjects (20.16 [20.04 to 20.30] %max/cm H 2 O; P = 0.02). Loop gain was elevated (more negative) in both overweight/obese groups and normal-weight control subjects (P = 0.02). Model-based analysis demonstrated that overweight/obese individuals without apnea rely on both more favorable anatomy and collapsibility and enhanced upper-airway dilator muscle responses to avoid OSA.Conclusions: Overweight/obese individuals without apnea have a moderately compromised upper-airway structure that is mitigated by highly responsive upper-airway dilator muscles to avoid OSA. Elucidating the mechanisms underlying enhanced muscle responses in this population may provide clues for novel OSA interventions.

show abstract

Section: Mechanisms Of Advantageous Physiology In Overweight and Obesmentioning

confidence: 99%

“…Because of increased fat deposition, overweight/obese individuals generally have a more collapsible airway than normal-weight individuals (4)(5)(6)(7)(8), yet the modest relationship between body mass index (BMI) and upper-airway collapsibility (3,9) indicates that some individuals gain weight without major upper-airway compromise.…”

mentioning

confidence: 99%