During sleep we relax. This also includes 90% of our muscles. But some muscles must still be active during sleep. The upper airway (throat, pharynx) is a flexible tube wich is held open trough the force of muscle activity. When those muscles responsible for a patent airway relax too much then flow limitation of air into the lungs occurs. This flow limitation can be partial when the upper airway is narrowed but not completely collapsed. This will happen during some forms of snoring. During obstructive sleep apnea the airway can completely or near completely collapse. Very little air or no air will then travel into the lungs. Hypoxia will result from it.
Nasal breathing problems and upper airway narrowing
Should you snore or suffer from obstructive sleep apnea syndrome a consultation by an ENT physician is recommended. We routinely collaborate with ENT collegues. Effective breathing during sleep requires unobstructed nasal passages (1). Polyps and nasal septum deviation can cause snoring. Further down a large soft palate, and large tonsils can contribute to a narrowing (2). And also in the tongue base region, tonsils of the tongue or a large tongue base (3) may be in part responsible for the narrowing.
In 75% of all individuals with snoring and sleep apnea 2 or more regions are affected. Thus, in most cases surgery in only one region of the upper airway will not help.
How your bony face is built may also have an impact on upper airway narrowing. People with long faces and/or small lower jaw are prone to also have a narrow upper airway. Wrong position of dental appliances during the childhood may also have contributed to upper airway narrowing.
As we grow older the composition of muscle tissue changes. Since the muscles are largely responsible for a patent upper airway during sleep this is also an important factor. However, the relative contribution of this factor seems to be weaker than that of other factors.
This is one of the most important factors. Neck circumferences greater than 17“ point to significant overweight. However, also individuals with normal weight can have severe obstructive sleep apnea. In those cases the above mentioned factors play a more important role in causing the problem.
Alcohol, nicotine, drugs, sleep loss
Those two glasses of wine in the evening, or a habit of smoking but also some drugs such as tranquillizers, and some allergy pills can have a relaxing effect on upper airway muscles. Long term smoking may have an adverse effect on receptors which are located in the mucosa of the upper airway and play an important role in upper airway control. And finally, it has been shown that sleep loss can also cause snoring and sleep apnea: “A tired brain will cause a tired muscle“.