Sleep Apnea

Medically Reviewed By William C. Lloyd III, MD, FACS

What is sleep apnea?

Sleep apnea is the name of a common condition characterized by interruption of breathing during sleep. (The word “apnea” means cessation of breathing.) This interruption of breathing causes an abnormal blood oxygen level, resulting in fatigue, as well as cardiovascular, cognitive and emotional disorders.

Sleep apnea is a common sleep disorder in the United States, affecting as many as 22 million Americans. However, many people—up to 80% of sufferers—are undiagnosed. The disease is more common in men, African Americans, Hispanics, and Pacific Islanders than in other groups. Further, at least 1 in 10 people older than 65 has sleep apnea.

Sleep apnea occurs due to two causes: obstruction of the airways and irregular brain signals. Most commonly, people develop sleep apnea from relaxation of soft tissue in the back of the throat that blocks the passage of air, resulting in obstructive sleep apnea (OSA). Central sleep apnea (CSA) is the result of irregularities in the brain’s normal signals to breathe. For both types of apnea, breathing may be interrupted as many as 20 to 30 or more times per hour, and each pause can last 10 seconds or longer.

The signs and symptoms of sleep apnea can last indefinitely or come and go. The disease course varies among individuals. Some people with sleep apnea have no symptoms, while others may have severe problems with sleep, decreases in blood oxygen levels (hypoxia), difficulty concentrating, irritability, and fatigue. Fortunately, there are successful treatments for sleep apnea, including lifestyle changes, breathing devices, and, in severe cases, surgery.

Seek immediate medical care (call 911) for serious symptoms, such as chest pain, headache, shortness of breath, severe sweating, or weakness or numbness on one side of the body.

What are the different types of sleep apnea?

There are three types of sleep apnea:

  • Central sleep apnea (CSA), in which the muscles controlling your breathing don’t receive proper signals from your brain, making it difficult for you to breathe normally. This type of sleep apnea is much less common than obstructive sleep apnea.
  • Complex sleep apnea syndrome, also known as mixed sleep apnea, is a combination of both OSA and CSA.
  • Obstructive sleep apnea (OSA), which occurs when your throat muscles relax during sleep, blocking your airway and preventing you from breathing properly. When this happens, your brain wakes you up quickly to restore breathing to normal. This is the most common type of sleep apnea.

What are the symptoms of sleep apnea?

Each type of sleep apnea causes similar symptoms to develop. For many people, loud snoring is often the first sign of a problem.

In severe cases, people with sleep apnea actually stop breathing while sleeping. This may be followed by an abrupt awakening where you experience shortness of breath as your body tries to reset itself. You may experience sleep apnea symptoms daily or just once in a while.

Common symptoms of sleep apnea

  • Decreased libido
  • Dryness in your throat when you wake up
  • Excessive daytime sleepiness
  • Memory problems
  • Morning headaches
  • Poor concentration
  • Snoring that can be loud and persistent
  • Urination at night

Serious symptoms that might indicate a life-threatening condition

In some cases, sleep apnea can be life-threatening. Seek immediate medical care (call 911) if you, or someone you are with, have any of these life-threatening symptoms:

  • Profuse sweating
  • Weakness (loss of strength) on one side of the body

What causes sleep apnea?

Sleep apnea is the result of physical obstruction in the airway or irregular brain signaling related to your breathing function. The disease is characterized by brief interruptions of breathing during sleep.

The most common type of sleep apnea is obstructive sleep apnea (OSA), caused by soft tissue or structural obstructions that restrict air flow through the windpipe. For this reason, sleep apnea occurs most frequently in people who are obese.

Central sleep apnea (CSA) is much less common, and occurs due to the brain failing to signal the respiratory system to breathe. Heart disease and stroke are commonly associated with CSA. Similar to OSA, this disorder results in waking with shortness of breath, snoring, and fatigue.

OSA causes of sleep apnea

In obstructive sleep apnea, shallow breathing or a pause in breathing happens because certain tissues or structures narrow or block part of the airway, which includes the nose, mouth, throat and windpipe. The tongue, tonsils, relaxed throat muscles, or extra fat around the windpipe can contribute to obstructive sleep apnea.

Other OSA causes of sleep apnea include:

  • Alcohol or drug use before bedtime
  • Large tongue and tonsils compared with the opening of the windpipe
  • Low soft palate
  • Shape of the head and neck that creates a smaller airway size
  • Throat muscles and tongue relax more than normal

CSA causes of sleep apnea

CSA causes of sleep apnea include any brain disorder, disease or condition that decreases the brain’s signals to the respiratory system to breathe. These can include:

  • Heart failure
  • Opioid use
  • Stroke
  • Very high altitudes

The natural aging process can also limit the ability of brain signals to keep the throat muscles stiff during sleep. This increases the likelihood that the airway will narrow or collapse.

What are the risk factors for sleep apnea?

A number of factors increase the risk of developing sleep apnea. Not all people with risk factors will get sleep apnea. Risk factors for sleep apnea include:

  • Acromegaly (a condition in which the pituitary gland produces excess growth hormone)
  • African American, Hispanic, and Pacific Islander race
  • Age over 40
  • Alcohol or sedative use
  • Excess weight
  • Family history of sleep apnea
  • Male biological sex; twice as many males than females have sleep apnea
  • Narrow airway
  • Neck circumference greater than 17 inches (43 centimeters)
  • Tonsillar hypertrophy in children

Reducing your risk of sleep apnea

You may be able to lower your risk of sleep apnea by:

  • Avoiding alcohol and sleeping medications
  • Avoiding driving or operating heavy machinery when feeling sleepy
  • Keeping nasal passages open
  • Losing excess weight
  • Sleeping on your side or on your stomach

What are the diet and nutrition tips for sleep apnea?

Because sleep apnea is so strongly linked to obesity, losing weight or maintaining a healthy weight are critical steps in managing your risk of the condition. By working with your doctor and possibly a nutritionist, you can build a diet and nutrition plan that meets your weight loss goals.

Healthy diet and nutrition tips that can lower risk of sleep apnea include:

  • Avoiding late-night meals or snacks before bed
  • Cooking meals at home
  • Drinking water
  • Eating breakfast each morning
  • Limiting alcohol, particularly before bed
  • Minimizing processed and fried foods, packaged snacks, and high-sugar treats
  • Reducing red meat
  • Slowing down and eating smaller portions

What are some conditions related to sleep apnea?

Breathing-related sleep problems include:

  • Child sleep apnea, considered a subtype of obstructive sleep apnea, often due to large tonsils and adenoids relative to throat size.
  • Infant sleep apnea, which tends to be either mixed (in small premature infants) or central sleep apnea (in larger premature infants and full-term babies). Most cases resolve in less than a year.
  • Snoring, which is the sound of vibrating tissues in the throat as air passes over them, usually upon inhale. Snoring tends to run in families and is associated with sleep apnea.

How do doctors diagnose sleep apnea?

Most people with sleep apnea do not know they have a problem. A family member may be the first to point out the signs, such as snoring and gasping for air when transitioning out of apnea.

An accurate diagnosis of sleep apnea requires a sleep study. This test can be performed at home or in a sleep lab. One part of the test is polysomnography. It records the patient’s body functions during sleep, including pauses in breathing, brain electrical activity, and blood oxygen levels. The other part of a sleep study is the multiple sleep latency test, which simply measures how fast the patient falls asleep.

The sleep study records the number of sleep apnea events to generate an AHI, or apnea-hypopnea index. The AHI includes complete pauses (apnea) and shallow breathing (hypopnea).

The categories of sleep apnea are:

  • No sleep apnea: fewer than 5 AHIs
  • Mild sleep apnea: 5 to 15 AHIs
  • Moderate sleep apnea: 15 to 30 AHIs
  • Severe sleep apnea: more than 30 AHIs

Your doctor will also ask about your symptoms to make a sleep apnea diagnosis. Daytime sleepiness, fatigue, concentration and memory lapses, headaches upon waking, and sexual dysfunction are just some of the symptoms to consider. In children, symptoms of sleep apnea may include bedwetting, hyperactivity, and learning or academic problems.

What are the treatments for sleep apnea?

Because each person is unique, there’s no one-size-fits-all approach to treating sleep apnea. The type of treatment for sleep apnea depends on the cause and severity of the condition and your individual medical history.

Lifestyle changes for sleep apnea

The mainstay of treatment for sleep apnea is lifestyle changes including:

  • Avoiding alcohol and sleeping medications
  • Keeping nasal passages open
  • Losing excess weight
  • Sleeping on your side or on your stomach
  • Sleeping with a special pillow or mouthpiece to keep your airway open

Device treatments for sleep apnea

Additional treatments for sleep apnea are sleeping devices. A primary therapy is positive airway pressure, which uses a machine to control airflow through a mask the patient wears. Types of devices to treat sleep apnea include:

  • Automatic positive airway pressure (APAP), which adjusts airflow based on the person’s stage of sleep and current breathing pattern
  • Continuous positive airway pressure (CPAP), which provides a steady stream of airflow
  • Oral appliances, custom-fit devices that reposition the lower jaw and tongue to more fully open the airway during sleep
  • Variable positive airway pressure (brand name VPAP), also known as bi-level positive airway pressure (brand name BIPAP), which alternates between two levels of airflow based on inhalation and exhalation. These types of PAP machines typically are used by patients with underlying respiratory conditions, such as COPD or by people who have had difficulty adjusting to CPAP.

Additional treatments for sleep apnea

Therapy for sleep apnea is specifically designed for each patient. These treatments may be used in conjunction with lifestyle changes and devices to address sleep apnea symptoms.

  • Implant placement, including an implant that stimulates airway muscles and a nerve stimulator implant. An implant may help manage central sleep apnea.
  • Orofacial therapy, exercises to improve tongue position and strengthen oral muscles
  • Surgery including placement of implants and tonsillectomy and other operations to enlarge the airway for obstructive sleep apnea

How does sleep apnea affect quality of life?

Severe obstructive sleep apnea can have a negative impact on quality of life, mood, attentiveness, and functional ability, based on standard and sleep-specific quality of life questionnaires completed by patients. In one study, the impact on quality of life was greatest among females who reported daytime sleepiness.

Some studies have shown limited differences regardless of sleep apnea severity, but other studies clearly show reduced quality of life even for patients with mild apnea. These differences may be due to patient age, coexisting conditions, and the questionnaires used in the studies.

What are the potential complications of sleep apnea?

Hypoxia, a complication of sleep apnea, can be serious and even life-threatening in some cases. You can minimize your risk of serious complications by following the treatment plan you and your healthcare professional design specifically for you and taking all medication as prescribed.

Left untreated, prolonged hypoxia can lead to serious consequences including:

  • Adverse effects of treatment
  • High blood pressure (hypertension)
  • Heart attack (myocardial infarction)
  • Stroke
  • Transient ischemic attack (temporary stroke-like symptoms that may be a warning sign of an impending stroke)
  • Work-related and driving accidents

Does sleep apnea shorten life expectancy?

Sleep apnea causes a momentary pause in breathing, but breathing does not stop long enough to cause death. The brain senses the drop in oxygen in the blood and triggers breathing to resume.

However, sleep apnea raises the risk of several life-threatening medical conditions, including coronary artery disease and heart attack, stroke, and arrhythmia. It also increases the risk of sudden cardiac death (SCD). In a study of 10,701 patients, obstructive sleep apnea was found to be an independent risk factor for SCD; people with the lowest nighttime blood oxygen levels had an 81% increase in risk of SCD. Abnormal heart rhythms triggered by apnea are thought to be the primary cause of SCD.

Sleep apnea awareness

A recent analysis estimated the cost of undiagnosed sleep apnea at nearly $150 billion, including lost productivity and accidents from fatigue, according to the American Academy of Sleep Medicine. The projected cost of treating complications of sleep apnea is an additional $30 billion.

Sleep Apnea Awareness week is in March.

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  6. What is VPAP? Is it different than APAP and CPAP?.
Medical Reviewer: William C. Lloyd III, MD, FACS
Last Review Date: 2021 Mar 7
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