Dr. Beatrice Neufeldt reports on current topics
What Are Sleep Apnea Causes?
Sleep apnea can have many different causes. To understand how these factors affect nighttime breathing, it’s helpful to understand the mechanics of obstructive sleep apnea (OSA). During your waking hours, the muscles in the back of your throat are active and keep your airway open easily. These muscles prevent the soft tissues in your mouth and throat from interfering with your breathing. Your soft palate, uvula (the dangling thing in the back of your mouth), your tongue and your tonsils are held away from your airway so there’s plenty of room for air to pass in and out. However, when you sleep, the muscles in your throat tend to relax. Your airway may narrow as the soft tissues in your mouth and throat “collapse” into your airway, restricting or blocking the flow of air.
The narrower your airway becomes, the more your air intake is compromised. Your breathing may become very shallow or stop altogether for 10-20 seconds at a stretch. As your blood oxygen level decreases and your brain senses that you can’t breathe properly, you experience a startle response that brings you partway back to waking consciousness. However, these awakenings are usually so brief that you don’t remember them. You may think you got a full night’s sleep – except you feel tired when you wake up. That’s not surprising when you realize that these episodes of poor breathing can occur five to 30 times per hour.
What Can Obstruct Your Airway?
There are many factors involved in the development of OSA. The more of the problems on the list below you experience, the more likely you are to have chronic and/or severe sleep apnea.
High Body Weight
Obesity is one common sleep apnea cause. It’s unclear precisely how high body weight interferes with breathing during sleep. However, individuals who carry a lot of extra fat in their trunk and neck area seem to experience narrowing of their airway as a result. If you have put on a significant number of pounds over the years, you may think that the fatigue you feel is from carrying around that extra weight. In fact, the weight may be contributing to apnea which makes you feel tired and less likely to exercise. It’s a vicious cycle that can lead to even more health problems over time. Weight reduction is a well-established method for reducing the severity of sleep apnea. However, that’s a long-term solution. You may need immediate treatment with a CPAP mask so you have enough energy to exercise regularly.
Habits such as sleeping on your back may put you at higher risk for experiencing airway obstruction. In this position, your tongue may tend to relax backward down your throat. You won’t actually choke to death on your tongue, but it can cause enough restriction in your breathing to interfere with normal sleep. If your partner notices that you snore more when you are on your back, your tongue position may be the problem. You may need to adjust your sleep posture to avoid lying on your back.
A small or receding jaw can be a contributing factor in sleep apnea. That’s because the size and shape of your jaw determines where your tongue is positioned in your mouth. A mouth guard that moves your jaw slightly forward may be useful for keeping your airway open at night.
If you have enlarged tonsils or adenoids, these can also obstruct your airway. This problem is most common in children. However, as routine tonsillectomy has become less popular, many adults now experience this problem as well. Tonsil and adenoid removal may resolve OSA in these cases.
Nasal issues are another frequently diagnosed sleep apnea cause. The condition may be temporary such as congestion from a cold or allergies. Or, there can be a permanent physical abnormality such as a deviated septum (crookedness in the cartilage or bone inside the nose) or nasal polyps. Treating the symptoms of congestion, alleviating allergies, or undergoing nasal surgery may limit apnea going forward.
What you put into your body can have a profound effect on your ability to breathe well during sleep. Smoking can irritate and inflame your upper respiratory tract, causing swelling in the tissues and constriction of the airway. Alcohol, sleeping pills and certain sedatives can cause excessive relaxation of the throat muscles, making sleep apnea symptoms worse. Avoiding substances that are known to contribute to OSA is one way to cut down on breathing problems at night.