Sleep Apnea
In this condition factsheet:
The Facts on Sleep Apnea
Sleep apnea is a condition in which disturbed breathing interrupts sleep. Obstructive sleep apnea (OSA), the most common type of sleep apnea, affects approximately 24% of middle-aged men and 9% of middle-aged women in Canada.
Most people suffering from sleep apnea also snore, but there's a big difference between the two conditions. While snoring can be annoying, sleep apnea can be life-threatening. During an apnea episode, the body's oxygen levels can drop noticeably, carbon dioxide builds up, and the heart has to work harder to cope. Each time it happens, the brain sends a wake up signal so that the person can breathe, and this means never getting a good night's sleep.
Untreated sleep apnea can cause dangerous daytime sleepiness as well as contribute to a higher risk of high blood pressure, stroke, and heart attack.
Causes of Sleep Apnea
There are 3 types of sleep apnea:
Obstructive sleep apnea (OSA), the most common type, happens when air cannot get into the lungs because the upper airway has collapsed. It's more common in men and in people who are overweight, especially those who sleep on their backs. In people of normal weight who have the condition, there's often an abnormality in the lower face, such as having a small chin, an overbite, or a large tongue. OSA typically has three phases:
- First, the airway is partly blocked as the soft tissue at the back of the throat relaxes and starts to close up, causing very loud snoring.
- Eventually, the airway collapses and airflow through it either stops totally or is significantly diminished for at least 10 seconds and up to 2 minutes.
- Finally, the sufferer wakes up briefly (although they are rarely aware of it), and often snorts or gasps for air. Once a breath is taken, the person falls back asleep and the cycle repeats itself.
Central sleep apnea, which is quite rare, results when the brain fails to send normal signals to the chest to breathe properly while asleep. Neurologic disease (i.e., disease of the brain) and severe heart disease can cause central sleep apnea, as can certain medications (especially strong pain medications like morphine and other narcotics).
Mixed sleep apnea, as the name suggests, is a combination of the first two types. It always starts out as central sleep apnea, and then turns into OSA.
Symptoms and Complications of Sleep Apnea
Unfortunately, most people with sleep apnea don't even know they have it. An estimated 30% of Canadian adults are at high risk for having or developing sleep apnea. The American Sleep Apnea Association has come up with a simple quiz to help people find out if they have sleep apnea. If you answer "yes" to any of the following questions you should talk to a doctor:
- Are you a loud, habitual snorer?
- Do you feel tired and groggy when you wake up?
- Are you often sleepy during the day?
- Are you overweight?
- Are you known to choke, gasp, or hold your breath while asleep? (You may want to ask your partner about this.)
Daytime sleepiness is probably the most important symptom that people notice, since it can make it hard to stay awake, concentrate, and work. People can even end up losing their jobs if they're always nodding off during the day. An especially dangerous problem is drowsiness while driving or operating machinery. People with sleep apnea get into more accidents than average. It's best for people with sleep apnea to avoid driving if they feel sleepy, or to stop driving completely until their condition is under control.
Sleep apnea can also lead to headaches, memory problems, and depression. In severe cases, complications including high blood pressure, heart attacks, strokes, and abnormalities in heart function, such as heart failure and arrhythmias (irregular heartbeat), can develop or worsen due to sleep apnea.
