Pharyngeal structure and function as a determinant of sleep-related breathing disorders: a unifying hypothesis.

We propose a hypothesis which relates the pathogenesis of various sleep-related breathing disorders such as snoring, obstructive sleep apnea, and central sleep apnea to pharyngeal structure and function, i.e. pharyngeal area and compliance; these easily measured mechanical properties of the pharynx reflect the complex integrated response of upper airway muscles to changes in neural drive. Our arguments, although hypothetical, are based on the already existing measurements of pharyngeal dynamics in patients with sleep-related breathing disorders. If confirmed, this hypothesis would allow to predict a particular breathing disorder occurring during sleep from simple mechanical measurements performed in an awake subject, and furthermore it would help us to understand the effect of recent therapeutic modalities used in treatment of sleep apnea.