Search Menu
Search entire library by keyword
Choose by letter to browse topics
A B C D E F G H I J K LM N O P Q R S T U V W X Y Z 0-9
(A-Z listing includes diseases, conditions, tests and procedures)

Sleep Apnea: Diagnosis, Treatment and Research


As many as 20 million people in the United States have obstructive sleep apnea, a condition in which the body does not breathe properly during sleep, resulting in involuntary breathing pauses. For those with sleep apnea, the airway collapses on itself and temporarily blocks airflow. Reflexes then tighten the airway muscles to allow breathing to resume. When breathing resumes, the patient may awaken with a gasp, snore or snort.

People who have sleep apnea may experience daytime sleepiness. They may also awaken with a headache, sore throat or dry mouth. Because obstructive sleep apnea is often most pronounced during rapid eye movement (REM) sleep, people who suffer from it may notice issues related to memory, learning consolidation and even sexual function — all of which are strongly influenced by REM sleep.

“However, some people who are later diagnosed with severe sleep apnea may not have any significant daytime or nighttime symptoms,” says Johns Hopkins sleep expert Jonathan Jun. Often, these patients visit the sleep clinic after their bed partner expresses concern after witnessing them snoring or stopping breathing at night. For this reason, listening to a bed partner’s observations can be an important way to diagnose sleep apnea that would otherwise go unnoticed by the sleeper.

Without treatment, sleep apnea can deprive your body of deep sleep, blocking its restorative properties. This can lead to dangerous problems with alertness and concentration. In addition, sleep apnea stresses your heart, blood vessels and metabolism, and it may lead to stroke, cardiovascular disease and type 2 diabetes, says Jun.

Risk Factors

“One of the greatest risk factors for sleep apnea is obesity,” says Jun. Men also have a higher prevalence of sleep apnea than women, and the risk increases with age for both men and women. Here is some insight into these and other risk factors associated with sleep apnea.

Age and Gender. As we grow older, the overall strength of skeletal muscles decreases, which may make older adults more vulnerable to sleep apnea. Also, women experience greater vulnerability to sleep apnea after menopause, due to hormone changes.

Ethnicity. People who are Asian, Latino or African-American are at a greater risk of sleep apnea than Caucasians.

Genetics. Sleep apnea tends to run in families, so experts believe there may be a genetic component to it. Some genetic disorders such as Down syndrome can increase a person’s risk of sleep apnea, because of anatomical differences in the mouth and upper airway.

Facial structure. An enlarged tongue, recessed jaw, narrow airway, enlarged tonsils or uvula, or other anatomical factors may predispose a person to sleep apnea. Among children, the top cause of sleep apnea is enlarged tonsils.

Pregnancy. Physical changes due to pregnancy can also be a trigger.

Drugs, smoking and alcohol. These substances can affect the upper airway by dulling protective reflexes or causing inflammation.

Diagnosis & Treatment


Sleep apnea is diagnosed with an overnight sleep study (polysomnogram), says Jun. These studies usually take place in a sleep laboratory, where the patient’s brain waves, eye movement, muscle activity, heart rate and breathing during sleep are monitored. Home testing is possible, but it may be less effective at picking up milder cases.

Sleep apnea is diagnosed based upon the patient’s apnea-hypopnea index (AHI), or the average number of apneic events (breathing pauses) recorded per hour of sleep. An AHI of 5 results in a diagnosis of sleep apnea, though there are levels of severity:

  • Mild: 5 to 15 episodes
  • Moderate: 15 to 30 episodes
  • Severe: More than 30 episodes


With proper treatment, sleep apnea symptoms can usually be completely controlled or eliminated. Current options include:

  • Continuous positive airway pressure (CPAP) machine: This is the gold standard for the treatment of sleep apnea. CPAP works by pushing air into the nose or mouth, which prevents the upper airway from collapsing during sleep. The level of pressure is customized to the patient based on a CPAP titration study, or sometimes with automatic CPAP machines. People with difficulty tolerating their CPAP should discuss their concerns with their health care provider, says Jun. Modifications to the settings or a different type of mask may be all that’s needed to remedy the problem.
  • Mandibular advancement device (MAD): These dental devices are worn at night to move the jaw into a position that will open the airway by lifting the tongue off the back of the throat.
  • Surgery: Surgeons may make modifications to open the airway by removing large tonsils or reducing the size of the tongue or uvula. If obesity is a contributing factor, bariatric or weight-loss surgery may be helpful.

Living With …

These lifestyle and behavioral changes may also help reduce the symptoms of sleep apnea.

Quit smoking. Smoking causes inflammation that narrows the airway. Kicking the habit may help minimize sleep apnea symptoms.

Modify use of alcohol and medications. Alcohol and certain medications (such as opiates, sedatives and muscle relaxants) can increase relaxation of the muscles in and around the upper airway. Avoid alcohol after dinner, avoid combining alcohol and sedative medications, and talk to your doctor about whether your medications may be worsening your sleep apnea.

Achieve a healthy weight. For most people, weight loss of 10 percent can reduce the number of apneic events.

Sleep on your side. For some people with sleep apnea, lying on their back can worsen sleep apnea symptoms due to the effects of gravity. There are pillows and devices that can help you stay on your side during sleep, which may minimize symptoms. Some people sew a tennis ball into the back of a T-shirt to prevent them from rolling onto their back.

Communicate with your surgeon. People who have sleep apnea are at a greater risk of certain complications during and after surgery. Because anesthesia affects breathing, people with sleep apnea may need special monitoring during and after surgery. They may also experience extended recovery times afterward. If you have sleep apnea, it’s important to share that information with all your health care providers.

Related Conditions

Sleep apnea has been linked to an increased risk of stroke, hypertension, irregular heartbeat, heart attack, type 2 diabetes, death from any cause, cancer and accidents on the road and at work due to daytime drowsiness. “Generally, the higher the number of sleep interruptions per night, the greater your risk of these problems. However, we are still learning what factors cause some people to be especially vulnerable,” says Jun. In addition, Jun points out that obesity may be leading to both sleep apnea and these other health problems — so weight loss for overweight/obese adults with sleep apnea is essential.


Johns Hopkins researchers are looking at novel therapies to treat sleep apnea. They are also further studying its causes and effects in the body. Among their recent studies:

Find a physician at another Johns Hopkins Member Hospital:
Connect with a Treatment Center:
Find Additional Treatment Centers at: