How is OSA Diagnosed?
If you suspect that you might have OSA, the most definitive way to diagnose OSA and its severity is through a detailed, overnight sleep study at the lab. However, in some cases, a home sleep apnoea test may also suffice.
Nonetheless, preliminary investigations will involve a physical exam whereby the doctor will examine your mouth, throat and nose for any extra or enlarged tissues; advise you on any current medications that might affect sleep quality; as well as take basic measurements such as weight and blood pressure.
Overnight Sleep Study (Polysomnography)
There are 2 main types of in-lab sleep studies: the full-night and split-night one.
You will be required to sleep overnight at a sleep clinic while you are hooked
up to various sensors on multiple parts of the body. The purpose is to record
vital information such as brain waves, heart rate, blood oxygen levels,
breathing patterns, air movement through the nose and arm and leg movement.
You will only be monitored for the first half of the night. If diagnosed with clinically significant OSA
then, the medical team may request that you try on the Continuous Positive Airway Pressure (CPAP) device
for the second half of the night. In a CPAP titration study, the air compressor increases the pressure of
the air inhaled until the optimum pressure is reached—the pressure that resolves the disordered breathing
The in-lab option may be recommended if the patient does not have a high risk of OSA, or if the patient has
some major medical issues such as heart and lung conditions, in which case an in-lab study will be the safest
and most comprehensive examination of one’s sleep.
Home Sleep Apnoea Testing
As the name suggests, this form of testing can be conducted at home. You will be required to attach a variety
of sensors and equipment to your body as instructed. These sensors will collect information on your breathing
patterns, blood oxygen level, heart rate and so on.
The home testing option may be recommended if it is very likely that the patient has moderate to severe OSA,
and has no major medical issue besides the suspected OSA.
However, if the home test did not record enough data or hints at a different sleep disorder, you may be
redirected to an in-lab study instead for a more accurate diagnosis.