What is the most common cause of obstructive sleep apnea (OSA) in patients with Down syndrome?

The most common cause of obstructive sleep apnea (OSA) in patients with Down syndrome is macroglossia, which refers to an abnormally large tongue. In individuals with Down syndrome, macroglossia can lead to a significant obstruction in the upper airway during sleep. The enlarged tongue can contribute to a narrowing of the airway, increasing the likelihood of apnea events when the individual is lying supine. This anatomical feature is particularly influential in the pathophysiology of OSA as it directly affects the airway structure and function.

While large adenoids and obesity can contribute to OSA in the general population, macroglossia is more specifically associated with the craniofacial characteristics seen in individuals with Down syndrome. Additionally, nasal congestion may also play a role in sleep-disordered breathing, but it is not as predominant a factor as macroglossia in this demographic. Thus, macroglossia stands out as a primary anatomical cause linked explicitly to the heightened prevalence of OSA among patients with Down syndrome.