The Effect of Mouth Closure on Airflow in OSA

Mass General Brigham

Status: Completed

Conditions: Hypopnea, Sleep

Treatments: Other: Mouth closure

Study type: Interventional

Funder types: Other; NIH

Identifiers

NCT06547658

R01HL128658 (U.S. NIH Grant/Contract)

2019P002847

Details and patient eligibility

About

Mouth breathing is associated with increased airway resistance, pharyngeal collapsibility, and obstructive sleep apnea (OSA) severity. It is commonly believed that closing the mouth can mitigate the negative effects of mouth breathing during sleep. However, we propose that mouth breathing serves as an essential route bypassing obstruction along the nasal route (e.g., velopharynx). The present study investigates the role of mouth breathing as an essential route in some OSA patients and its association with upper airway anatomical factors.

Participants underwent drug-induced sleep endoscopy (DISE) with simultaneous pneumotach airflow measurements through the nose and mouth separately. During the DISE procedure, alternating mouth closure (every other breath) cycles were performed during flow-limited breathing.

We evaluated the overall effect mouth closure on inspiratory airflow, and the change in inspiratory airflow with mouth closure across three mouth-breathing quantiles. We also evaluated if velopharyngeal obstruction was associated with mouth breathing and a negative airflow response to mouth closure.

Enrollment: 66 patients

Sex: All

Ages: 18 to 89 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Diagnosed obstructive sleep apnea (AHI > 5 events/h).
• Scheduled to undergo clinical drug-induced sleep endoscopy.

Exclusion criteria

• pregnancy
• age under 18 years
• poor general health
• allergy to propofol or dexmedetomidine
• history of surgical treatment for sleep apnea, such as palate, tongue base, or epiglottis surgery.

Trial design

Primary purpose: Treatment

Allocation: Non-Randomized

Interventional model: Crossover Assignment

Masking: None (Open label)

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66 participants in 2 patient groups

Mouth closed

Experimental group

Description:

Closing the mouth by applying pressure to the mentum until the teeth were in occlusion, without altering the head position. Performed during flow-limited breathing.

Treatment:

Other: Mouth closure

Mouth relaxed

No Intervention group

Description:

Mouth in the natural relaxed position during sleep.