How is obstructive sleep apnoea diagnosed

 You should consult your GP if you have any of the main symptoms of sleep apnoea:

  • your breathing stops and starts while you sleep
  • you make gasping, snorting or choking noises while you sleep
  • you always feel very tired during the day

Sleep apnoea can be serious if it is not diagnosed and treated.

Doctors SomnoMed Consultation

Getting tested for sleep apnoea

If your GP thinks you might have sleep apnoea, they will refer you to a specialist sleep clinic for tests. If someone else has witnessed your symptoms, it can help to take them with you to this appointment.

Your GP should prioritise you for rapid assessment by a sleep service if any of the following apply, so ensure you let your GP know if this is the case:

• you have a vocational driving job DVLA advice
• you have a job for which vigilance is critical for safety
• you have unstable cardiovascular disease
• you are pregnant
• you are undergoing preoperative assessment for major surgery


At the clinic, you will be asked questions about your sleep quality and how this affects the way you feel and function during the day.  It is likely that you will be asked to fill in a questionnaire such as the Epworth Sleepiness Scale (ESS), which is intended to measure daytime sleepiness using a very short questionnaire.  You can fill this in below and take your score with you to your appointment. 

You may be asked to fill in the STOP-BANG Questionnaire, a tool that has been proven to be efficient in screening for OSA.  This will assess your sleep apnoea group, whether you belong to a low, moderate or high group.  The link above will take you to the STOP-BANG website, again you can take your result to your appointment.

Home sleep study

You are most likely to be given a device to take home with you and asked to wear this overnight so doctors can check for signs of sleep apnoea.  This will indicate things like:

  • Snoring and body position
  • Oxygen level and heart rate
  • Apnoea-Hypopnoea Index (AHI) severity

The device can show if you have sleep apnoea and how severe it is based on how often your breathing stops, for 10 seconds or more, while you sleep (AHI score).

  • AHI of 5 to 14 – mild
  • AHI of 15 to 30 – moderate
  • AHI over 30 – severe

Overnight sleep study (Polysomnography or PSG)

The clinic may decide that an overnight sleep study is more appropriate, especially if they are not sure what type of sleep disorder you have.

A PSG is a study done while you’re asleep. A technician will observe you as you sleep and record data about your sleep patterns.   The following are monitored to help chart your sleep cycles:

  • brain waves
  • skeletal muscle activity
  • blood oxygen levels
  • heart rate
  • breathing rate
  • eye movement

Observing your sleep cycles, along with your body’s reactions to the changes in these cycles, can help identify disruptions in your sleep patterns (i.e. how many times you keep waking up at night).

Once you have been diagnosed with Obstructive Sleep Apnoea the doctor will then recommend the appropriate treatment.