Sleep Apnea
Repeated narrowing or closure of the upper airway during sleep, causing breathing pauses and fragmented sleep.
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Key takeaways
- Definition of an apnea: breathing stops for 10 seconds or more
- Classic signs: loud snoring, witnessed pauses or gasping, daytime sleepiness
- Most useful single change: Ask whoever sleeps near you whether you stop breathing or gasp.
- Commonest mistake: Driving when sleepy, or ignoring falling asleep during the day.
- See a doctor if any of the signs under "When to get help" below apply to you.
Why it matters
It is strongly linked to high blood pressure, atrial fibrillation, stroke and drowsy-driving crashes, and many people who have it are undiagnosed.
The numbers, in one place
| Measure | Figure |
|---|---|
| Definition of an apnea | breathing stops for 10 seconds or more |
| Classic signs | loud snoring, witnessed pauses or gasping, daytime sleepiness |
| Standard treatment, moderate to severe | CPAP |
| Diagnosis | a sleep study, often done at home |
| Driving | drowsy driving is dangerous; some jobs have specific medical rules |
What helps
- Ask whoever sleeps near you whether you stop breathing or gasp
- Try side sleeping and cutting evening alcohol while awaiting assessment
- Stick with CPAP through the first difficult couple of weeks
- Treat weight loss and nasal blockage as part of the picture
What to avoid
- Driving when sleepy, or ignoring falling asleep during the day
- Anti-snoring gadgets as a substitute for assessment if you have pauses
- Alcohol or sedatives at night, which worsen airway collapse
In depth
Obstructive sleep apnea happens when the muscles in the throat relax during sleep and the airway narrows or closes. Breathing becomes shallow or stops for 10 seconds or more, oxygen levels may fall, and the brain briefly wakes you to reopen the airway. These awakenings are usually too short to remember, but they can happen many times an hour, leaving sleep fragmented and unrefreshing even after a full night in bed.
Each pause triggers a surge of stress hormones that raises heart rate and blood pressure. Over months and years, this repeated strain is linked to high blood pressure that is hard to control, atrial fibrillation, heart failure, stroke and type 2 diabetes. Daytime sleepiness also increases the risk of drowsy-driving crashes and accidents at work. Many people with sleep apnea do not know they have it, because the main signs happen while they are asleep.
A less common form, central sleep apnea, occurs when the brain does not send the usual signals to breathe, and it is associated with conditions such as heart failure and certain medicines. Obstructive sleep apnea is far more common. It is diagnosed with a sleep study and is treatable. CPAP is the standard treatment for moderate to severe cases, and other options exist for people who cannot use it or who have milder disease.
Signs and symptoms
- Loud, regular snoring, often worse on your back
- Pauses in breathing, choking or gasping noticed by a bed partner
- Waking unrefreshed even after a full night in bed
- Excessive daytime sleepiness or falling asleep without meaning to
- Morning headaches or a dry mouth on waking
- Waking often to urinate during the night
- Poor concentration, irritability or low mood
Causes and risk factors
- Excess weight, especially around the neck
- Male sex, older age and post-menopausal changes in women
- A narrow airway, small jaw, large tongue or enlarged tonsils
- Alcohol, sedatives and some sleep medicines, which relax throat muscles
- Nasal congestion or blockage
- Smoking and a family history of sleep apnea
How it is checked
Your doctor will ask about snoring, witnessed pauses, daytime sleepiness and medical history, and may use questionnaires such as the Epworth Sleepiness Scale or STOP-BANG. If sleep apnea is suspected, they will arrange a sleep study. This may be a home sleep apnea test, which records breathing, oxygen and airflow while you sleep in your own bed, or an overnight study in a sleep lab for more complex cases.
The study measures how many times per hour your breathing stops or becomes shallow, known as the apnea-hypopnea index. Generally, 5 to 15 events an hour is classified as mild, 15 to 30 as moderate and more than 30 as severe. Your doctor uses this, along with your symptoms and other health conditions, to recommend treatment.
Related topics
- Atrial Fibrillation: What the Evidence Actually Says (Heart Health)
- What the Guidance Really Says About Shift Work and Health (Workplace Health)
- What the Guidance Really Says About Sleep and the Brain (Brain Health)
- Teen Sleep: What Published Guidance Supports (Teen Health)
Where to go next
- A Q and A on Sleep Apnea
- Sleep Apnea at a Glance
- Sleep: The Complete Guide
- Caffeine and Sleep: Sorting the Evidence From the Noise
- Shift Work and Sleep: Sorting the Evidence From the Noise
When to get help
See your doctor if you snore loudly and wake unrefreshed, if anyone has seen you stop breathing or gasp, or if you fall asleep without meaning to during the day, and do not drive while excessively sleepy. Call 911 for chest pain, sudden severe shortness of breath, or signs of stroke such as face drooping, arm weakness or trouble speaking.
Where this comes from
- National Heart, Lung, and Blood Institute — Sleep Apnea
- American Academy of Sleep Medicine — Obstructive Sleep Apnea
How this page was put together
Every figure, recommendation and warning above is taken from the guidance named in Where this comes from. Nothing on this page is inferred, summarized or generalized beyond what those bodies publish: where they give a number, it is their number, and where they are silent, so are we. Pages are rebuilt whenever the underlying record changes. Sign-off by a named clinician, where it has happened, is shown at the top of the page along with the date.
Medical disclaimer
This article is general information, not medical advice. It cannot account for your own history, medication or circumstances. Always speak to your doctor, pharmacist or another qualified health professional before making changes that affect your treatment, and never delay seeking medical advice because of something you have read here. In an emergency, call 911.