Laryngeal Hyposensitivity in Obstructive Sleep Apnea.

Area of Science:

• Otolaryngology
• Sleep Medicine
• Neuroscience

Background:

• Impaired laryngopharyngeal sensation is a potential factor in obstructive sleep apnea (OSA).
• The laryngeal adductor reflex (LAR) is a key indicator of laryngeal sensory function.

Purpose of the Study:

• To evaluate laryngeal sensory function in adults with OSA.
• To assess the laryngeal adductor reflex (LAR) response rate and temporal profile in OSA patients.

Main Methods:

• Laryngeal sensation testing was conducted on awake adults with and without OSA.
• Tactile stimulation was applied to the medial aryepiglottic fold or arytenoid using monofilaments.
• Video analysis assessed LAR presence and latency to vocal fold adduction.

Main Results:

• OSA patients showed significantly lower LAR response rates compared to controls for both 4-0 (38.3% vs 86.9%) and 5-0 (27% vs 63.9%) stimulation.
• Mean LAR latency was shorter in OSA patients (123.7 ms) than in controls (156.4 ms).
• OSA LAR latency positively correlated with the apnea-hypopnea index, indicating a link to disease severity.

Conclusions:

• The OSA group demonstrated reduced LAR response rates and shortened LAR latency.
• Findings affirm laryngeal hyposensitivity and altered sensorimotor temporal dynamics in OSA.
• Potential mechanisms include decreased receptor sensitivity, increased sympathetic tone, and altered brainstem function.