Apnea (Pauses in Breathing)

What apnea means

The word comes from the Greek for "without breath". Doctors use several related terms:

In adults, an AHI of 5 to 14 is mild sleep apnea, 15 to 29 is moderate and 30 or more is severe.

Obstructive sleep apnea

The commonest form. During sleep, the muscles of the throat relax, and in susceptible people the soft tissues collapse and block the airway. Oxygen falls until the brain triggers a brief awakening, often with a snort or gasp, and breathing restarts. This can happen hundreds of times a night without the person remembering it. See obstructive sleep apnea.

Risk factors include:

• excess weight, especially a thick neck (over 43 cm or 17 in in men, 41 cm or 16 in in women)
• male sex, older age and menopause
• large tonsils or adenoids, a small jaw, a large tongue or a deviated septum
• alcohol, sedatives and sleeping pills
• sleeping on your back
• smoking and nasal congestion

Central sleep apnea

Less common. The airway is open but the drive to breathe pauses. Causes include heart failure (often with a waxing and waning pattern called Cheyne-Stokes breathing), stroke, opioid medicines, high altitude, and some neurological conditions. It can also appear when CPAP is started.

Apnea in babies and children

Newborns often show periodic breathing: pauses of 5 to 10 seconds followed by rapid breaths. This is normal and needs no treatment if the baby stays pink and alert.

Concerning causes of apnea in infants include:

• Apnea of prematurity: in babies born before about 34 weeks; usually resolves by around the original due date or a few weeks after
• Infections: RSV, whooping cough and sepsis can cause apnea in young babies, sometimes before other symptoms
• Reflux and choking during or after feeds
• Seizures, low blood sugar, anemia and heart problems

A brief episode in which a baby stops breathing, changes color or goes limp, then recovers, is called a BRUE (brief resolved unexplained event) and should always be assessed.

In children, obstructive sleep apnea usually comes from enlarged tonsils and adenoids. Signs include snoring, pauses, restless sleep, bedwetting, mouth breathing, and daytime hyperactivity or poor concentration rather than sleepiness. See tonsillar hypertrophy.

Symptoms that suggest sleep apnea

Night-time:

• loud, regular snoring
• pauses in breathing seen by a partner
• waking with gasping or choking
• getting up to urinate often at night
• restless sleep and night sweats

Daytime:

• excessive sleepiness and dozing off when inactive
• morning headaches and a dry mouth
• poor concentration, memory and mood
• low sex drive

Why apnea matters

Untreated moderate or severe sleep apnea is linked to high blood pressure, atrial fibrillation, heart failure, stroke, type 2 diabetes, depression and road accidents from drowsy driving. Treatment improves sleepiness and quality of life and can lower blood pressure.

How apnea is diagnosed

1. History: snoring, witnessed pauses, sleepiness (often scored on the Epworth Sleepiness Scale), weight and medicines.
2. Examination: neck size, nose, throat, tonsils, jaw and blood pressure.
3. Sleep study: a home sleep apnea test records breathing, oxygen and pulse overnight. An in-lab polysomnogram adds brain waves, muscle activity and video and is needed for suspected central apnea, children and complex cases.
4. Other tests: heart tests if heart failure is suspected, and brain imaging for some central apnea.

Babies with apnea are assessed in hospital with monitoring, blood tests and sometimes infection tests and an ECG.

Treatment

• CPAP (continuous positive airway pressure): a mask delivers gentle air pressure that holds the airway open. It is the most effective treatment for moderate to severe obstructive apnea.
• Oral appliances: a custom mouthguard moves the lower jaw forward; useful for mild to moderate apnea or people who cannot use CPAP.
• Weight loss: losing 10 percent of body weight can substantially reduce apnea severity.
• Positional therapy for apnea that occurs mainly on the back.
• Avoid alcohol and sedatives in the evening.
• Surgery: tonsil and adenoid removal is first-line in most children; adults may be offered nasal, throat or jaw surgery, or a hypoglossal nerve stimulator.
• For central apnea: treating heart failure, reducing opioids, and specialized ventilation devices.
• For babies: caffeine for apnea of prematurity, treating infection or reflux, and monitoring.

Frequently asked questions

What is apnea?

Apnea is a temporary pause in breathing. In adults, sleep studies count pauses lasting 10 seconds or more. It most often happens during sleep, either because the throat is blocked (obstructive) or because the brain briefly stops signaling the breathing muscles (central).

How long can apnea last?

Most sleep apneas last 10 to 30 seconds, though some last a minute or more. They can recur dozens or hundreds of times a night. The body restarts breathing by briefly waking you, which is why sleep is fragmented and unrefreshing.

Is apnea in babies normal?

Short pauses of under about 10 to 15 seconds, followed by normal breathing, are common in newborns and called periodic breathing. Pauses of 20 seconds or more, or any pause with color change, limpness or a slow heart rate, are not normal and need urgent care.

Can apnea be cured?

Sometimes. Removing large tonsils in children often cures it. In adults, weight loss, jaw surgery or treating the cause of central apnea can resolve it. Many adults manage it long term with CPAP or an oral appliance, which controls symptoms well.

What happens if sleep apnea is not treated?

Untreated apnea causes daytime sleepiness, poor concentration and mood problems, and raises the risk of high blood pressure, heart rhythm problems, heart failure, stroke, type 2 diabetes and car crashes. Treatment reduces these risks and usually improves energy quickly.