How is OSA diagnosed?

Find out how OSA is diagnosed, including what happens at a sleep clinic, the tests that are used in a sleep study, and how you can get the right treatment

When to see your GP

If you have any signs or symptoms of OSA, speak to your GP. Getting a diagnosis of OSA can help you get the right treatment and advice about lifestyle changes that can help.

It can also help your doctor see if your OSA is mild, moderate or severe. This helps them work out the best treatment plan for you.

Diagnosing OSA early can reduce your risk of complications.

At the appointment, your GP will ask about your symptoms, health, medical history and about how sleepy you are when awake. 

They’ll also ask you about any other health conditions you have. This is because some other conditions, including other lung conditions, can increase your chances of getting OSA.

You might find it helpful to keep a symptom and sleep diary to take to your GP appointment. Ask people you’re close to about any symptoms too.  

 

Take a note of: 

  • night-time symptoms

  • day-time symptoms

  • when your symptoms have been better

  • when your symptoms have been worse

  • how your symptoms have affected you at work.

See your GP if you think your child has OSA 

It’s important to diagnose OSA early in children. If OSA is not diagnosed and properly treated, it can lead to other problems, including with behaviour and learning.

Your GP can check your child’s symptoms. If they have typical OSA symptoms, your child should be referred to a sleep clinic for tests to get a firm diagnosis.

Sleepiness questionnaires 

Your GP may use the Epworth Sleepiness Scale test. This helps your GP see how sleepy you feel during the day, and how likely you are to fall asleep in everyday situations.  

They may also use the STOP-Bang questionnaire. This questionnaire helps them check your risk of OSA based on your symptoms, and whether you’re very overweight (obese) or have high blood pressure.

Based on your scores and how sleepiness affects you, your GP may refer you to a sleep clinic. This is so you can do further tests, including a sleep study, to diagnose OSA. The tests will also show if your OSA is mild, moderate or severe.

 

Your GP may be able to refer you more quickly if you: 

  • are pregnant

  • have a job that involves driving

  • are going to have major surgery soon

  • have heart rhythm problems

  • have high blood pressure.

If you think you need a quicker referral, talk to your GP.

You can check your sleepiness using the Epworth sleepiness scale test. Take your results to your GP. 

What happens at a sleep clinic?

Sleep clinics are specialist clinics that assess, diagnose and treat people with a range of sleep problems, including OSA.

At the sleep clinic you’ll have an assessment and some physical checks.

Sleep clinic assessment 

Your assessment may include questions to help the specialist team understand more about your sleep and how tired you are, including questions about: 

  • how long you sleep and the quality of your sleep  

  • your symptoms and how long you have had them 

  • your smoking history 

  • family history of sleep disorders, such as OSA or narcolepsy 

  • your mental health 

  • any medication you use or have used 

  • how sleepy you are during the day 

  • working patterns and timings – what times you work, and if you work shifts 

  • the effect of your symptoms on your work and how well you can concentrate. 

Physical checks 

This can include measuring your: 

  • weight and height to find your body mass index (BMI) 

  • blood pressure 

  • neck circumference (size) 

  • jaw size  

It also involves assessing: 

  • your face and jaw appearance and symmetry 

  • the airflow in your nose 

  • your upper airway to see if it’s obstructed 

  • your teeth and having a look at the size of your tongue 

  • the inside of your mouth.  

The sleep clinic may also arrange for you to have a sleep study. 

What is a sleep study?

A sleep study is a test to diagnose sleep disorders. It uses special equipment to monitor you while your sleep.

A sleep study can test different things while you’re asleep including:

  • your breathing rate and depth

  • the amount of oxygen in your blood

  • brain activity

  • heart rate

  • eye and leg movements.

Tests used to diagnose OSA include respiratory polygraphy and oximetry. These sleep tests can usually be done at home.

If the diagnosis is not clear after respiratory polygraphy, or you have a range of different symptoms, you may need polysomnography. This is more detailed sleep monitoring which is done in hospital.

Find out more about breathing sleep tests and how you can prepare for your sleep test whether it’s at home, or in a clinic.

 

Your OSA sleep test results

The results from a sleep study can help diagnose OSA and show whether it’s severe, moderate or mild. This helps your doctor prescribe the right treatment plan for you. 

Doctors work out how severe your OSA is by counting the number of breathing pauses (apnoeas) you had in an hour during your sleep study. They do this using the AHI index (apnoea-hypnoea index). Your oxygen level during sleep is also very important.

Once they know how much your OSA symptoms affect you, they can decide what treatment to start you on. If your OSA is mild, it may be that you do not need any treatment. Instead you can try making some lifestyle changes and look at your sleep habits.

If your OSA is moderate to severe, your doctors should start you on OSA treatments like Continuous Positive Airways Pressure (CPAP).

Get support

Call or WhatsApp our Helpline for support with your condition. Get advice on your medicines, symptoms or travelling with a lung condition, or just call us to say hello.

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