For normal function of your body regardless of the sleep, your cells need oxygenated blood. That means environment air need to reach your lungs through nose or mouth.
Then this oxygen is mixed with your blood & carried to the all your organs inside via blood due to the pumping action of the heart.
Obstructive sleep apnea (OSA)—is a sleep disorder that involves cessation or significant decrease in airflow in the presence of breathing effort. It is the most common type of sleep-disordered breathing.
OSA is characterized by recurrent episodes of upper airway collapse during sleep.
Therefore you will not get enough oxygenated blood to your organs & that will make you to awake repeatedly during your sleep. Sometimes you may not notice this sleep disturbance but in the morning you will feel drowsy & sleepy.
So who are the people at risk of not getting air to your lungs during sleep?
1. Obese people
2. People having a very small lower jaw (Micrognathia). Usually they have this since their birth.
3. Large tongue- people having hormonal problems like high growth hormones (acromegaly), low thyroid hormones (hypothyroidism)& amyloidosis are likely to have large tongues. This large tongue can block your throat during the sleep.
4. Having a short neck
5. Large tonsils- Your tonsils may be inflammed & enlarged due to an infection in the throat.
Dr. Yapa Wijeratne