Sleep Apnea

Sleep apnea is a common disorder that can be very serious. In sleep apnea, your breathing stops or gets very shallow while you are sleeping. Each pause in breathing typically lasts 10 to 20 seconds or more. These pauses can occur 20 to 30 times or more an hour.

The most common type of sleep apnea is obstructive sleep apnea. During sleep, enough air cannot flow into your lungs through your mouth and nose even though you try to breathe. When this happens, the amount of oxygen in your blood may drop. Normal breaths then start again with a loud snort or choking sound.

When your sleep is upset throughout the night, you can be very sleepy during the day. With sleep apnea, your sleep is not restful because:

• These brief episodes of increased airway resistance (and breathing pauses) occur many times.
• You may have many brief drops in the oxygen levels in your blood.
• You move out of deep sleep and into light sleep several times during the night, resulting in poor sleep quality.

People with sleep apnea often have loud snoring. However, not everyone who snores has sleep apnea. Some people with sleep apnea don’t know they snore.

• Sleep apnea happens more often in people who are overweight, but even thin people can have it.
• Most people don’t know they have sleep apnea. They don’t know that they are having problems breathing while they are sleeping.
• A family member and/or bed partner may notice the signs of sleep apnea first.

Untreated sleep apnea can increase the chance of having high blood pressure and even a heart attack or stroke. Untreated sleep apnea can also increase the risk of diabetes and the risk for work-related accidents and driving accidents.

Symptoms

The most common signs of sleep apnea are:

• Loud snoring
• Choking or gasping during sleep
• Fighting sleepiness during the day (even at work or while driving)

Your family members may notice the symptoms before you do. Otherwise, you will likely not be aware that you have problems breathing while you are asleep.

Other signs of sleep apnea may include:

• Morning headaches
• Memory or learning problems
• Feeling irritable
• Not being able to concentrate on your work
• Mood swings or personality changes; perhaps feeling depressed
• Dry throat when you wake up
• Frequent urination at night

Diagnosis

Your doctor will do a physical exam and take a medical history that includes asking you and your family questions about how you sleep and how you function during the day. As part of the exam, your doctor will check your mouth, nose, and throat for extra or large tissues; for example, tonsils, uvula (the tissue that hangs from the middle of the back of the mouth), and soft palate (the roof of your mouth in the back of your throat).

Your doctor may order a sleep recording of what happens with your breathing while you sleep. A sleep recording is a test that is often done in a sleep center or sleep laboratory, which may be part of a hospital. You may stay overnight in the sleep center, although sleep studies are sometimes done in the home. The most common sleep recording used to find out if you have sleep apnea is called a polysomnogram, or PSG. This test records:

• Brain activity
• Eye movement
• Muscle activity
• Breathing and heart rate
• How much air moves in and out of your lungs while you are sleeping
• The percentage of oxygen in your blood

A PSG is painless. You will go to sleep as usual. The staff at the sleep center will monitor your sleep throughout the night. The results of your PSG will be analyzed by a sleep medicine specialist to see if you have sleep apnea, how severe it is, and what treatment may be recommended.

In certain circumstances, the PSG can be done at home. A home monitor can be used to record your heart rate, how air moves in and out of your lungs, the amount of oxygen in your blood, and your breathing effort. For this test, a technician will come to your home and help you apply the monitor that you will wear overnight. You will go to sleep as usual, and the technician will come back the next morning to get the monitor and send the results to your doctor.

Once all your tests are completed, the sleep medicine specialist will review the results and work with you and your family to develop a treatment plan. In some cases, you may also need to see another physician for evaluation of:

• Lung problems (treated by a pulmonologist)
• Problems with the brain or nerves (treated by a neurologist)
• Heart or blood pressure problems (treated by a cardiologist)
• Ear, nose, or throat problems (treated by an ENT specialist)
• Mental health, such as anxiety or depression (treated by a psychologist or psychiatrist)

Causes

Sleep apnea happens when enough air cannot move into your lungs while you are sleeping. When you are awake, and normally during sleep, your throat muscles keep your throat open and air flows into your lungs. In obstructive sleep apnea, however, the throat briefly collapses, causing pauses in your breathing. With pauses in breathing, the oxygen level in your blood may drop. This happens if the following conditions occur:

• Your throat muscles and tongue relax more than is normal.
• Your tonsils and adenoids are large.
• You are overweight. The extra soft tissue in your throat makes it harder to keep the throat area open.
• The shape of your head and neck (bony structure) results in somewhat smaller airway size in the mouth and throat area.

With the throat frequently fully or partly blocked during sleep, enough air cannot flow into your lungs, even though your efforts to breathe continue. Your breathing may become hard and noisy and may even stop for short periods of time (apneas).

Central apnea is a rare type of sleep apnea that happens when the area of your brain that controls your breathing doesn’t send the correct signals to the breathing muscles. Then there is no effort to breathe at all for brief periods. Snoring does not typically occur in central apnea.

Reference:

National Heart, Lung and Blood Institute, USA.