High Tongue Position is a Risk Factor for Upper Airway Concentric Collapse in Obstructive Sleep Apnea: Observation Through Sleep Endoscopy

Abstract

Purpose

Identification of upper airway (UA) obstruction based on pharyngeal factors is important for obstructive sleep apnea (OSA) evaluation. This study is to assess the association between UA collapse characteristics and Friedman tongue position (FTP) in patients with OSA through drug-induced sleep endoscopy (DISE).

Patients and Methods

Retrospective study in individuals with OSA who were intolerant to continuous positive airway pressure (CPAP) treatment, submitted to DISE between June 1, 2013, and July 31, 2017. All subjects were classified as having an FTP grade of I to IV, and the velum, oropharynx, tongue base, epiglottis (VOTE) classification was used to analyze the DISE findings. UA collapse characteristics by DISE and FTP grading were compared between groups. The associations between specific DISE findings and FTP were analyzed.

Results

In total, 205 patients were assessed. A positive and significant correlation was identified between the presence of retropalatal complete concentric collapse (CCC) and FTP grade, according to the following distributions: I, 17.4%; II, 22.9%; III, 33.7%; and IV, 48.7% (P = 0.014). A logistic regression model revealed that CCC was associated with FTP grade IV. After adjusting for age, sex, body mass index (BMI), and tonsil size (TS), the grade IV individuals had a 4.4-fold higher risk of having CCC than grade I individuals (P = 0.026). Multiple collapse sites and palatopharyngeal or combined (palatopharyngeal and hypopharyngeal) collapse were more prevalent in grade IV individuals.

Conclusion

OSA patients intolerant to CPAP have a strong positive correlation between the FTP grade and presence of retropalatal CCC. FTP grade IV is an independent risk factor for velum-CCC, controlling for sex, age, BMI, and TS grade.

Keywords:

• drug-induced sedation endoscopy
• sleep endoscopy
• obstructive sleep apnea
• tongue position
• upper airway collapse
• complete concentric collapse

Ethics Approval

All procedures performed in this study were in accordance with the ethical standards of the Institutional Review Board and Hospital Research Ethics Committee of Stanford Hospital and Clinics (Protocol 35,054). Patient informed consent was waived because of the retrospective nature of this research. The patients’ data were maintained with confidentiality and in compliance with the Declaration of Helsinki.

Disclosure

Dr Robson Capasso reports personal fees from and served at the advisory board for Invicta Medical, outside the submitted work. The authors report no other conflicts of interest in this work.