Why does sleep apnea cause fatigue?

Why does sleep apnea cause fatigue?

We’ve all had nights where we don’t get enough sleep. If you suffer from any form of sleep apnea, you are having more than one of those nights. Your sleep could be interrupted as many as hundreds of times a night by closures in your airway that occur during an apneic event. Obstructive sleep apnea (OSA) is when your muscles relax and cause a full or partial blockage.  OSA is the most common form of sleep apnea.

When you snore, your sleep is interrupted because your body will send a wake-up signal to your brain, causing you to awaken just enough to restore your muscle tone and open your throat to breathe. This same wake-up signal can also occur if you suffer from central sleep apnea (CSA), which is a form of sleep apnea where your brain doesn’t tell your body to keep breathing when you sleep.

If your body is constantly waking itself up, you are not allowing yourself to go through the entire four-stage sleep cycle—including the deep, restorative stages. Instead, you are constantly going in and out of the initial stages, never reaching the critical deep sleep stages where your body can fully rest.

If you don’t enter these deep sleep stages, you aren’t getting the rest you need to allow your body to fully repair itself. When you don’t get enough sleep, you will lack energy and feel fatigued, constantly trying to catch up on your sleep.

If you leave your sleep apnea untreated, dismissing it as annoying snoring, you could face more serious consequences besides feeling tired all the time. Fatigue puts you at risk for accidents, both at work and while driving. Untreated sleep apnea is also associated with other serious health conditions like heart disease, stroke, diabetes and others.


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