Understanding Sleep Apnea

With the rising obesity epidemic in America, we are going to see more and more people who have sleep apnea. When casually used, the term 'sleep apnea' refers to the obstructive sleep apnea. In OSA, brain sends signal to breath, the chest moves up and down, but due to obstruction in the back of throat, there is reduced air flowing in to the lungs. There is another type of apnea known as central sleep apnea- that is when there the brain does not send signal to breath, and there is no chest effort and no flow of air to the lungs. When patients have both obstructive and central sleep apnea, then it is known as complex sleep apnea.

Even though we associate OSA with obesity, not all patients who are obese will have sleep apnea, and not all patients with OSA are obese. The other two factors besides BMI that are responsible for OSA include- upper airway anatomy and muscle tone.

Upper airway structure that results in crowded back of the throat can result in OSA, even in thin, fit people-  we look for large tongue, large tonsils, adenoids, high arched palate, receding lower jaw, known as retrognathia.

Poor muscle tone can lead to OSA as well. People who drink alcohol have their muscle tones relaxed resulting in a higher chance of snoring and sleep apnea. Patients taking narcotics or muscle relaxants like flexeril, or soma also can worsen their risk for OSA. I know of at least one research study published out of Brazil where they showed that neck muscle toning exercises can help improve mild to moderate OSA.

Every time there is an obstruction of the throat due to OSA, the brain gets panic signals and it goes into "microarousal"- so the sleep is very fragmented in patients with OSA- so they feel really tired and often sleepy in daytime. Every time there is choking and obstruction of throat, the adrenal galnds pump stress hormones resulting in heart rate and blood pressure going up and down all night long. The oxygen levels keeps dropping down with apnea. So, night time, which is supposed to be restful and rejuvenating for our system, becomes more like a battlefield. This puts a lot of strain on the blood vessels, the heart, and of course, the brain. There is also more inflammation in the body. The insulin does not work too well in patients with OSA. Due to all these bad changes in body overnight in patients with OSA, there is a higher risk of heart attack, atrial fibrillation, hypertension, congestive heart failure and strokes. Men, especially, have a 3-4 fold higher risk of stroke if they have OSA. Due to fragmented sleep in patients with OSA, they are tired, with reduced attention span, and they have a slightly higher risk of accidents as well. This is why the Federal DOT requires that truck dirvers, rail engineers, pilots, etc have medical check up to screen for and if needed full evaluation for OSA.

A good night's sleep for at least 8 hours is vital for good health.