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Overview

What Is Obstructive Sleep Apnoea?

OSA stands for obstructive sleep apnea, a condition in which the upper airway repeatedly narrows or closes during sleep. These blockages reduce or briefly stop airflow, even though the body continues trying to breathe. OSA can affect adults and children, and nighttime breathing problems may disturb sleep without the person realizing it. Learning what is OSA can help people recognize symptoms and seek appropriate care.

Symptoms

Obstructive Sleep Apnoea Symptoms

OSA symptoms may occur during sleep or while a person is awake the next day. A bed partner or family member may notice nighttime signs that the person with OSA does not notice themselves. Daytime symptoms can result from fragmented sleep and reduced alertness.

  • Loud snoring
  • Witnessed pauses in breathing (apneas)
  • Gasping or choking during sleep
  • Morning headache
  • Dry mouth on waking
  • Daytime sleepiness
  • Difficulty concentrating
  • Irritability

Causes

What Causes Obstructive Sleep Apnoea?

During sleep, the muscles that support the throat naturally relax. If the upper airway is narrow or lacks enough support, it can partly or completely collapse. Breathing effort continues, but airflow is reduced or blocked until the airway opens again, causing repeated oxygen changes and brief sleep disruptions.

  • A naturally narrow upper airway or certain jaw and facial structures
  • Enlarged tonsils, adenoids, or other tissues that narrow the airway
  • Reduced muscle tone in the throat during sleep
  • Sleep-related changes in breathing control and airway stability

Risk Factors

Obstructive Sleep Apnoea Risk Factors

Factors that cannot be changed

  • Older age
  • Family history of OSA
  • Craniofacial features that narrow the airway
  • Enlarged tonsils or adenoids
  • Menopause-related changes in adults who are postmenopausal

Factors that may be addressed

  • Excess body weight
  • Alcohol use, especially near bedtime
  • Sedative use
  • Smoking
  • Persistent nasal obstruction
  • Certain medical conditions, including some heart, hormone, and metabolic disorders

Complications

Obstructive Sleep Apnoea Complications

Repeated oxygen reductions, disrupted sleep, and daytime sleepiness may affect health and daily functioning. Untreated or inadequately treated OSA is associated with longer-term health risks, although the level of risk differs from person to person.

  • High blood pressure
  • Cardiovascular disease
  • Worsening metabolic health
  • Mood changes or difficulty with thinking and memory
  • Motor-vehicle or workplace safety risks related to excessive sleepiness

Diagnosis

How Obstructive Sleep Apnoea Is Diagnosed

Diagnosis begins with a medical history, a review of symptoms, and a physical examination. A clinician may ask about sleepiness, snoring, witnessed breathing pauses, gasping, medications, and coexisting conditions. The evaluation helps determine whether sleep testing is appropriate and which type of test is most suitable.

Home sleep apnea test

A home sleep apnea test may be considered for selected adults who have a high likelihood of uncomplicated OSA. It records a limited set of breathing and oxygen signals while the person sleeps at home.

In-lab sleep study

An in-lab polysomnogram provides broader monitoring during an overnight stay. It may be preferred when more detailed information is needed or when other sleep disorders, medical conditions, or complex breathing problems are possible.

Clinicians interpret breathing events, oxygen changes, sleep-related signals, and the overall clinical picture to determine whether OSA is present and how severe it is. Test results are considered alongside symptoms and other health conditions rather than in isolation.

Treatment & Management

Obstructive Sleep Apnoea Treatment and Management

OSA treatment is tailored to its severity, airway anatomy, symptoms, preferences, and other medical conditions. Treatment may combine more than one approach, and the best option can change as health, weight, anatomy, or treatment response changes.

  • Positive airway pressure, such as CPAP
  • Weight-management support when appropriate
  • Positional therapy to reduce back-sleeping when advised
  • Oral appliances fitted by a qualified clinician
  • Treatment of persistent nasal obstruction
  • Selected surgery or implanted therapies for appropriate patients

Ongoing management and follow-up

Prevention

Can Obstructive Sleep Apnoea Be Prevented?

OSA cannot always be prevented, particularly when inherited or anatomical factors contribute to airway narrowing. However, addressing modifiable contributors may lower risk or reduce worsening. These steps do not replace evaluation or treatment when symptoms are present.

  • Maintain a healthy weight when appropriate
  • Limit alcohol, especially near bedtime
  • Avoid non-prescribed sedatives
  • Do not smoke
  • Ask a clinician about persistent nasal obstruction
  • Follow medical advice for related health conditions

Outlook and Prognosis

Obstructive Sleep Apnoea Outlook and Prognosis

With effective treatment, many people experience better nighttime breathing, improved sleep quality, and greater daytime alertness. Consistent management may also reduce health and safety risks associated with untreated OSA. OSA may persist or recur if contributing factors change, so long-term follow-up is often important.

  • OSA severity
  • Consistency with prescribed treatment
  • Changes in weight or airway anatomy
  • Coexisting medical conditions
  • Response to follow-up adjustments

When Should You See a Doctor

When Should You See a Doctor for Obstructive Sleep Apnoea Symptoms?

Get medical advice

Do not ignore possible OSA

Contact a clinician about loud habitual snoring with witnessed pauses, repeated gasping or choking during sleep, or marked daytime sleepiness. Seek urgent help if sleepiness makes driving or operating machinery unsafe; obtain emergency care for severe breathing difficulty, chest pain, fainting, or inability to stay awake safely.