People who have this sleep disorder experience frequent, brief periods when breathing stops. These pauses in breathing — called apneic episodes — are caused by narrowed or blocked airways. Most often, the airways are narrowed because the muscles that support the soft tissues in the throat relax and reduce their normal size. This can prevent oxygen from flowing in and out of the lungs, which can lower the level of oxygen in the blood. This can damage the heart and other organs, increase the risk of stroke and coronary artery disease, cause high blood pressure and type 2 diabetes, and make you feel tired and irritable.

What Causes Sleep Apnea and How to Prevent It

What causes sleep apnea is the most common form of this disorder. It happens when the soft tissue in your throat collapses while you sleep, reducing or closing the airway and making it difficult to breathe. It’s more common in older men, but it can affect anyone, including children. It can also cause nasal congestion and lead to snoring.

Certain health conditions and medications can increase your risk for obstructive sleep apnea. Being overweight can make it harder to breathe, as can smoking and having a large overbite or other dental issues. Enlarged tonsils or adenoids, a thick neck, and some birth defects can also narrow the upper airway. Nasal congestion due to allergies or sinus problems can also contribute to obstructive sleep apnea. People who have congestive heart failure, high blood pressure, or type 2 diabetes are at higher risk of central sleep apnea. Using narcotic pain medicines, such as methadone, can increase your risk, too, as can a previous stroke.