Sleep apnea is a common condition in adults, and it can also occur in children. There are various factors that can lead to a narrowing or instability of the upper airway, which can cause the pauses in breathing characteristic of sleep apnea. As sleep apnea can have serious consequences in children, it is important to identify correctable causes. When considering these predisposing factors, they can be subdivided into several major categories:
Enlarged tonsils and adenoids
Perhaps the single most common contribution to sleep apnea in children relates to a narrowing of the anatomy of the upper airway. The tissues at the back of the mouth and throat called tonsils and adenoids are likely suspects. Just because enlargement of these tissues is present does not mean a child will have sleep apnea. However, those children with sleep apnea who have enlarged tonsils and adenoids may be significantly helped by removing them. Approximately 10 percent of children do not improve after surgery, and they may have other factors contributing to their condition.
Obesity among children is increasing, and it may have a greater role in causing sleep apnea as these trends continue. As the amount of fat lining the airway grows, it may lead to crowding and narrowing within the airway. Alternatively, extra weight outside of the airway may apply pressure and lead to the airway collapse, resulting in apnea events.
There are several abnormalities of the head or face (called craniofacial abnormalities) that may lead to an increased risk of developing sleep apnea. Conditions that decrease the size of the nose, mouth, and throat may lead to a collapse of the airway during sleep. For example, an enlarged tongue (called macroglossia) may contribute. Other conditions include:
- Midfacial hypoplasia (an underdevelopment of the nose and central face)
- Retrognathia or micrognathia (a recessed or small jaw)
- Narrow maxillary arch (the top of the mouth)
There are a group of rare disorders called mucopolysaccharidoses, or mucolipidoses, that may put children at increased risk of sleep apnea. This occurs because of the tissues in the upper airway accumulating large molecules and swelling in size. There are typically associated developmental abnormalities that are identified at birth or in early childhood, so most parents will be aware that their child has this condition.
Loss of the control of the musculature of the upper airway may also lead to sleep apnea. A change in muscle tone (called hypotonia if it is low, or hypertonia if it is high) may contribute. Compression of the brainstem (as may occur in Arnold Chiari malformations or in tumors) may lead to sleep apnea. There are some developmental abnormalities, such as Down syndrome, that lead to a high risk for the condition. In general, other problems will be identified beyond the sleep apnea to suggest the risk of more serious conditions.
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