What is Sleep Apnea?
Obstructive sleep apnea (or OSA) is a condition in which the back of your throat collapses during sleep, causing your airway to be blocked. Even though you are trying to breathe, the collapsed airway is blocking air from moving in and out of your lungs. After a period of no breathing (called apnea), you take a loud, deep breath (snort) to resume breathing. This may occur dozens of times each hour during sleep.
What are the effects of OSA?
The results of these periods of apnea are two-fold. When the apnea occurs, little or no air is getting into your lungs, which prevents oxygen from entering your bloodstream. When the blood oxygen level is low, this stresses your vital body organs, including the heart and brain. Over time, these repetitive cycles of low oxygen levels can cause damage to these organs.
The second effect is reduced quality of sleep. When the apnea occurs, the dropping oxygen level causes your brain to trigger an "arousal" which brings you out of deeper stages of sleep so you start to breathe again. Even though you may not completely wake up, these arousals may occur dozens of times each hour and the quality of your sleep is significantly reduced. This is especially true in terms of reducing the amount of deep sleep when the most restful period of sleep occurs. Because of these many arousals, the person with OSA often wakes up in the morning tired and is frequently very sleepy during the day.
What are the most common signs and symptoms of OSA?
The most common signs and symptoms of OSA include snoring, daytime sleepiness, morning headaches, impaired concentration/memory, pauses in breathing during sleep, waking up gasping for air and sexual dysfunction.
Although there are patients with OSA who are not overweight at all, most are significantly overweight. Certain body features are also associated with OSA, including a large neck circumference, deep-set chin and an enlarged tongue or tonsils. Middle-aged men are the most commonly affected, but it does occur in women (with increased risk after menopause) and even children can have it.
What happens if OSA goes untreated?
Clinical studies have shown when OSA goes untreated, it is associated with increased incidence of blood pressure, heart disease, diabetes and stroke. Untreated OSA is also associated with a significant increase in the risk of motor vehicle accidents due to daytime drowsiness. One study found the risk of accidents was greater in untreated OSA patients than in people who had been drinking alcohol.
How can OSA be diagnosed?
A diagnosis of OSA is suspected based on a review of your medical history and checking for the signs and symptoms mentioned previously. It is confirmed by performing a sleep test called "polysomnography" (or PSG). During this study, many measurements are taken during sleep to determine if you are having apneas or periods when airflow is reduced substantially (called hypopneas) and how often it occurs. From the testing, your doctor calculates your Apnea Hypopnea Index (or AHI). If your AHI is too high, it means you have OSA; the second part of the test evaluates treatment to determine the setting it takes to prevent the apneas from occurring.
How is OSA treated?
The good news is that OSA can be treated effectively. Proper treatment has been shown to reduce the risks associated with OSA (stroke, heart disease, etc.). The most common and effective treatment for OSA is continuous positive airway pressure, or CPAP as it is commonly called. CPAP works by applying a small amount of pressure to the airway through a mask that fits over the nose (called nasal mask) or nose and mouth (called full-face mask). The mask is connected via tubing to the CPAP machine that is set according to your doctor's prescription. This provides just enough pressure to the airway to keep it open during sleep and prevent the apneas. This positive pressure pushes out on the walls of the throat, creating an "air splint" within the airway in much the same way that air pressure within a balloon pushes out on the walls of the balloon and prevents it from collapsing.
Another type of treatment very similar to CPAP is bilevel positive airway pressure, commonly called BIPAP. BIPAP works the same as CPAP, only it uses two different pressures: one while the person inhales and a lower pressure while the person exhales. Many patients find the lower pressure during exhalation more comfortable and easier to breathe as the machine cycles to match normal breathing.
Other treatments have also been tried with lesser success, including surgery to remove excess tissue from the throat or advance the jaw, and use of devices that fit in the mouth to hold the jaw forward. CPAP and BIPAP remain the most effective treatments for the vast majority of OSA patients.
Is there anything else that helps OSA?
There are also lifestyle changes you can make that will help make your treatment more effective.
- Weight loss will help. Sustained weight loss best occurs by changing long-term habits of better eating and more activity.
- Drinking alcohol in the evening has been shown to increase the severity of apnea.
- Practice good sleep hygieneby getting up at the same time every morning and trying to allow time for at least seven hours of sleep. Reduce your consumption of caffeine, especially in the late afternoon or evening. Physical activity will also help but should take place earlier in the day, reserving more relaxing activities for closer to bedtime.
- Some patients experience OSA worse while sleeping on their back. If this is true for you, train yourself to sleep on your side.
If you have further questions about OSA and treatments, contact your physician. If you believe you would benefit from a sleep study, ask your doctor for a referral to the SJH Center for Sleep Medicine. If you still have questions or concerns, download a brochure or call (618) 651-2736.