Researchers have built a new model of the airway, which shows an important gender difference that has health implications. In sleep apnoea, the upper airway tends to collapse during sleep causing an obstruction to the free flow of air. This actually causes breathing to stop momentarily many times in the night, leading to daytime sleepiness and a higher risk of heart disease and stroke.
Men are far more prone to sleep apnoea than women and researchers in the US now believe they may have discovered the underlying reason. They have studied the anatomic and physiologic differences in the upper airway region between men and women. This has enabled them build an airway model that reveals the mechanical properties of the upper airway. They find that, regardless of height, the airway is always longer in men than in women. This difference makes the male airway more susceptible to collapse, the researchers say. This may be at least part of the reason why men are more susceptible to sleep apnoea than women are.